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177-632: Parts of the brain play an important role in this field. Neurons play the most vital role, since the main point is to establish an understanding of cognition from a neural perspective, along with the different lobes of the cerebral cortex . Methods employed in cognitive neuroscience include experimental procedures from psychophysics and cognitive psychology , functional neuroimaging , electrophysiology , cognitive genomics , and behavioral genetics . Studies of patients with cognitive deficits due to brain lesions constitute an important aspect of cognitive neuroscience. The damages in lesioned brains provide

354-555: A Black lens and dedicated her career to focusing on the anxiety of African American women. She founded the organization Rise Sally Rise which helps Black women cope with anxiety. She published her work Soothe Your Nerves: The Black Woman's Guide to Understanding and Overcoming Anxiety, Panic and Fear in 2003. In 2002 Dr. Teresa LaFromboise, former president of the Society of Indian Psychologists, received

531-457: A basophilic ("base-loving") dye. These structures consist of rough endoplasmic reticulum and associated ribosomal RNA . Named after German psychiatrist and neuropathologist Franz Nissl (1860–1919), they are involved in protein synthesis and their prominence can be explained by the fact that nerve cells are very metabolically active. Basophilic dyes such as aniline or (weakly) hematoxylin highlight negatively charged components, and so bind to

708-494: A bigger and more detailed look at brain tissue. This can help researchers understand more on anatomy and viability for their experiments. This technique has helped to see neurons, microglia, tumor cells and blood capillaries more closely. Shadow imaging is a new approach that shows a lot of promise in the field of neuroimaging. Another very recent trend in cognitive neuroscience is the use of optogenetics to explore circuit function and its behavioral consequences. This new technology

885-402: A biologically potent stimulus (e.g., food that elicits salivation) is paired with a previously neutral stimulus (e.g., a bell) over several learning trials, the neutral stimulus by itself can come to elicit the response the biologically potent stimulus elicits. Ivan Pavlov —known best for inducing dogs to salivate in the presence of a stimulus previously linked with food—became a leading figure in

1062-426: A bit less than 1/10 of a volt at baseline. This voltage has two functions: first, it provides a power source for an assortment of voltage-dependent protein machinery that is embedded in the membrane; second, it provides a basis for electrical signal transmission between different parts of the membrane. Numerous microscopic clumps called Nissl bodies (or Nissl substance) are seen when nerve cell bodies are stained with

1239-613: A certain area of the brain supports a given mental faculty. However, early efforts to subdivide the brain proved to be problematic. The phrenologist movement failed to supply a scientific basis for its theories and has since been rejected. The aggregate field view, meaning that all areas of the brain participated in all behavior, was also rejected as a result of brain mapping, which began with Hitzig and Fritsch 's experiments and eventually developed through methods such as positron emission tomography (PET) and functional magnetic resonance imaging (fMRI). Gestalt theory , neuropsychology , and

1416-569: A child should be recognized as their own person with their own right and have each session catered to the child's specific needs. She encouraged drawing, moving freely, and expressing themselves in any way. This helped build a strong therapeutic alliance with child patients, which allows psychologists to observe their normal behavior. She continued her research on the impact of children after family separation, children with socio-economically disadvantaged backgrounds, and all stages of child development from infancy to adolescence. Functional periodicity ,

1593-473: A comparable starting point on regards to healthy and fully functioning brains. These damages change the neural circuits in the brain and cause it to malfunction during basic cognitive processes, such as memory or learning . People have learning disabilities and such damage, can be compared with how the healthy neural circuits are functioning, and possibly draw conclusions about the basis of the affected cognitive processes. Some examples of learning disabilities in

1770-547: A concept of "recognition" ( pinyin : jen-shih ) which referred to the interface between individual perceptions and the socially accepted worldview; failure to correspond with party doctrine was "incorrect recognition." Psychology education was centralized under the Chinese Academy of Sciences , supervised by the State Council . In 1951, the academy created a Psychology Research Office, which in 1956 became

1947-544: A decrease in firing rate), or modulatory (causing long-lasting effects not directly related to firing rate). The two most common (90%+) neurotransmitters in the brain, glutamate and GABA , have largely consistent actions. Glutamate acts on several types of receptors and has effects that are excitatory at ionotropic receptors and a modulatory effect at metabotropic receptors . Similarly, GABA acts on several types of receptors, but all of them have inhibitory effects (in adult animals, at least). Because of this consistency, it

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2124-635: A degree of liberalization during the Khrushchev Thaw . The topics of cybernetics, linguistics, and genetics became acceptable again. The new field of engineering psychology emerged. The field involved the study of the mental aspects of complex jobs (such as pilot and cosmonaut). Interdisciplinary studies became popular and scholars such as Georgy Shchedrovitsky developed systems theory approaches to human behavior. Twentieth-century Chinese psychology originally modeled itself on U.S. psychology, with translations from American authors like William James,

2301-406: A dendrite to another dendrite. The signaling process is partly electrical and partly chemical. Neurons are electrically excitable, due to the maintenance of voltage gradients across their membranes . If the voltage changes by a large enough amount over a short interval, the neuron generates an all-or-nothing electrochemical pulse called an action potential . This potential travels rapidly along

2478-492: A fMRI and made it more efficient, in a technique called  direct imaging of neuronal activity or DIANA. This group of researchers changed the software to collect data every 5 milliseconds, which is 8 times faster than what the normal technique captures. After, the software can stitch together all of the images taken during the imaging and create a full slice of the brain. Experimental methods include: Related Wikibooks Neuron A neuron , neurone , or nerve cell

2655-622: A greater connection to physiology, emerged in South America, under the leadership of Horacio G. Piñero at the University of Buenos Aires . In Russia, too, researchers placed greater emphasis on the biological basis for psychology, beginning with Ivan Sechenov 's 1873 essay, "Who Is to Develop Psychology and How?" Sechenov advanced the idea of brain reflexes and aggressively promoted a deterministic view of human behavior. The Russian-Soviet physiologist Ivan Pavlov discovered in dogs

2832-780: A hiatus for World War I, the Seventh Congress met in Oxford, with substantially greater participation from the war-victorious Anglo-Americans. In 1929, the Congress took place at Yale University in New Haven, Connecticut, attended by hundreds of members of the APA. Tokyo Imperial University led the way in bringing new psychology to the East. New ideas about psychology diffused from Japan into China. American psychology gained status upon

3009-435: A laboratory procedure meant to study attachment style by separating and uniting a child with their mother several different times under different circumstances. These field studies are also where she developed her attachment theory and the order of attachment styles , which was a landmark for developmental psychology . Because of her work, Ainsworth became one of the most cited psychologists of all time. Mamie Phipps Clark

3186-714: A learning process that was later termed " classical conditioning " and applied the process to human beings. One of the earliest psychology societies was La Société de Psychologie Physiologique in France, which lasted from 1885 to 1893. The first meeting of the International Congress of Psychology sponsored by the International Union of Psychological Science took place in Paris, in August 1889, amidst

3363-418: A lot of new advancements in the field of Cognitive Nueroscience. One new technique that has emerged is called shadow imaging. This method has combined different aspects of various neuroimaging techinques to create one that is more versatile. It uses standard light microscopy and melds it with fluorescence labeling of the interstitial fluid in the brain's extracellular space. This technique can help researchers get

3540-748: A neuron leading to electrical activity, including pressure , stretch, chemical transmitters, and changes in the electric potential across the cell membrane. Stimuli cause specific ion-channels within the cell membrane to open, leading to a flow of ions through the cell membrane, changing the membrane potential. Neurons must maintain the specific electrical properties that define their neuron type. Thin neurons and axons require less metabolic expense to produce and carry action potentials, but thicker axons convey impulses more rapidly. To minimize metabolic expense while maintaining rapid conduction, many neurons have insulating sheaths of myelin around their axons. The sheaths are formed by glial cells: oligodendrocytes in

3717-465: A neuron responds at all, then it must respond completely. Greater intensity of stimulation, like brighter image/louder sound, does not produce a stronger signal but can increase firing frequency. Receptors respond in different ways to stimuli. Slowly adapting or tonic receptors respond to a steady stimulus and produce a steady rate of firing. Tonic receptors most often respond to increased stimulus intensity by increasing their firing frequency, usually as

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3894-460: A neurotransmitter that binds to chemical receptors . The effect on the postsynaptic neuron is determined by the type of receptor that is activated, not by the presynaptic neuron or by the neurotransmitter. A neurotransmitter can be thought of as a key, and a receptor as a lock: the same neurotransmitter can activate multiple types of receptors. Receptors can be classified broadly as excitatory (causing an increase in firing rate), inhibitory (causing

4071-517: A new applied psychology organization called the International Congress of Psychotechnics Applied to Vocational Guidance, later called the International Congress of Psychotechnics and then the International Association of Applied Psychology . The IAAP is considered the oldest international psychology association. Today, at least 65 international groups deal with specialized aspects of psychology. In response to male predominance in

4248-465: A power function of stimulus plotted against impulses per second. This can be likened to an intrinsic property of light where greater intensity of a specific frequency (color) requires more photons, as the photons can not become "stronger" for a specific frequency. Other receptor types include quickly adapting or phasic receptors, where firing decreases or stops with a steady stimulus; examples include skin which, when touched causes neurons to fire, but if

4425-509: A professor of psychology at the University of Pennsylvania and Columbia University and the co-founder of Psychological Review , was the first professor of psychology in the United States . The German psychologist Hermann Ebbinghaus , a researcher at the University of Berlin , was a 19th-century contributor to the field. He pioneered the experimental study of memory and developed quantitative models of learning and forgetting. In

4602-697: A psychologist and political activist has applied a black, feminist, and class lens to all her psychological studies. Aiding progressive and women's issues, she has been the executive director for many NGOs. In 2007 she became the Senior Director of the Women's Programs Office of the American Psychological Association. Therefore, she was one of the creators of the APA's "Women in Psychology Timeline" which features

4779-522: A religion established by Russian-American philosopher Helena Blavatsky , drew inspiration from these doctrines during her time in British India . Psychology was of interest to Enlightenment thinkers in Europe. In Germany, Gottfried Wilhelm Leibniz (1646–1716) applied his principles of calculus to the mind, arguing that mental activity took place on an indivisible continuum. He suggested that

4956-434: A sea change of opinion, away from mentalism and towards "behavioralism." In 1913, John B. Watson coined the term behaviorism for this school of thought. Watson's famous Little Albert experiment in 1920 was at first thought to demonstrate that repeated use of upsetting loud noises could instill phobias (aversions to other stimuli) in an infant human, although such a conclusion was likely an exaggeration. Karl Lashley ,

5133-666: A significant influence on psychology in China. Chancellor T'sai Yuan-p'ei introduced him at Peking University as a greater thinker than Confucius. Kuo Zing-yang who received a PhD at the University of California, Berkeley, became President of Zhejiang University and popularized behaviorism . After the Chinese Communist Party gained control of the country, the Stalinist Soviet Union became

5310-425: A technique called "double impregnation" and is still in use. In 1888 Ramón y Cajal published a paper about the bird cerebellum. In this paper, he stated that he could not find evidence for anastomosis between axons and dendrites and called each nervous element "an autonomous canton." This became known as the neuron doctrine , one of the central tenets of modern neuroscience . Psychology Psychology

5487-678: A time at Imperial University in Japan, with publications such as Clairvoyance and Thoughtography by Tomokichi Fukurai, but it was mostly shunned by 1913. As a discipline, psychology has long sought to fend off accusations that it is a "soft" science . Philosopher of science Thomas Kuhn 's 1962 critique implied psychology overall was in a pre-paradigm state, lacking agreement on the type of overarching theory found in mature hard sciences such as chemistry and physics. Because some areas of psychology rely on research methods such as self-reports in surveys and questionnaires, critics asserted that psychology

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5664-450: A total of 100,000 individual members. At least 30 other international organizations represent psychologists in different regions. In some places, governments legally regulate who can provide psychological services or represent themselves as a "psychologist." The APA defines a psychologist as someone with a doctoral degree in psychology. Early practitioners of experimental psychology distinguished themselves from parapsychology , which in

5841-456: A universal classification of neurons that will apply to all neurons in the brain as well as across species. This is done by considering the three essential qualities of all neurons: electrophysiology, morphology, and the individual transcriptome of the cells. Besides being universal this classification has the advantage of being able to classify astrocytes as well. A method called patch-sequencing in which all three qualities can be measured at once

6018-446: A wide range of topics related to mental processes and behavior. Typically the latter group of psychologists work in academic settings (e.g., universities, medical schools, or hospitals). Another group of psychologists is employed in industrial and organizational settings. Yet others are involved in work on human development , aging, sports , health, forensic science , education , and the media . The word psychology derives from

6195-463: Is NIRS which uses light absorption to calculate changes in oxy- and deoxyhemoglobin in cortical areas. In some animals Single-unit recording can be used. Other methods include microneurography , facial EMG , and eye tracking . Integrative neuroscience attempts to consolidate data in databases, and form unified descriptive models from various fields and scales: biology, psychology, anatomy, and clinical practice. Adaptive resonance theory ( ART )

6372-434: Is a cognitive neuroscience theory developed by Gail Carpenter and Stephen Grossberg in the late 1970s on aspects of how the brain processes information . It describes a number of artificial neural network models which use supervised and unsupervised learning methods, and address problems such as pattern recognition and prediction. In 2014, Stanislas Dehaene , Giacomo Rizzolatti and Trevor Robbins , were awarded

6549-495: Is a combination of genetic targeting of certain neurons and using the imaging technology to see targets in living neurons. This technique allows scientists to see the neurons while they are still intact in animals and be able to trace the electrical happenings in that cell. This new technology has been used successfully in many experiments and it is helping researchers in observing brain activity and understanding its role in disease, behavior and function. Researchers have also modified

6726-512: Is a cross-disciplinary, holistic model that concerns the ways in which interrelationships of biological, psychological, and socio-environmental factors affect health and behavior. Evolutionary psychology approaches thought and behavior from a modern evolutionary perspective. This perspective suggests that psychological adaptations evolved to solve recurrent problems in human ancestral environments. Evolutionary psychologists attempt to find out how human psychological traits are evolved adaptations,

6903-447: Is a neurological disorder that results from the demyelination of axons in the central nervous system. Some neurons do not generate action potentials but instead generate a graded electrical signal , which in turn causes graded neurotransmitter release. Such non-spiking neurons tend to be sensory neurons or interneurons, because they cannot carry signals long distances. Neural coding is concerned with how sensory and other information

7080-496: Is a powerful electrical insulator , but in neurons, many of the protein structures embedded in the membrane are electrically active. These include ion channels that permit electrically charged ions to flow across the membrane and ion pumps that chemically transport ions from one side of the membrane to the other. Most ion channels are permeable only to specific types of ions. Some ion channels are voltage gated , meaning that they can be switched between open and closed states by altering

7257-625: Is a synapse in which a neuron's axon connects to its dendrites. The human brain has some 8.6 x 10 (eighty six billion) neurons. Each neuron has on average 7,000 synaptic connections to other neurons. It has been estimated that the brain of a three-year-old child has about 10 synapses (1 quadrillion). This number declines with age , stabilizing by adulthood. Estimates vary for an adult, ranging from 10 to 5 x 10 synapses (100 to 500 trillion). Beyond electrical and chemical signaling, studies suggest neurons in healthy human brains can also communicate through: They can also get modulated by input from

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7434-568: Is an excitable cell that fires electric signals called action potentials across a neural network in the nervous system . Neurons communicate with other cells via synapses , which are specialized connections that commonly use minute amounts of chemical neurotransmitters to pass the electric signal from the presynaptic neuron to the target cell through the synaptic gap. Neurons are the main components of nervous tissue in all animals except sponges and placozoans . Plants and fungi do not have nerve cells. Molecular evidence suggests that

7611-423: Is an interdisciplinary area of study that has emerged from neuroscience and psychology . There are several stages in these disciplines that have changed the way researchers approached their investigations and that led to the field becoming fully established. Although the task of cognitive neuroscience is to describe the neural mechanisms associated with the mind, historically it has progressed by investigating how

7788-419: Is common for neuroscientists to refer to cells that release glutamate as "excitatory neurons", and cells that release GABA as "inhibitory neurons". Some other types of neurons have consistent effects, for example, "excitatory" motor neurons in the spinal cord that release acetylcholine , and "inhibitory" spinal neurons that release glycine . The distinction between excitatory and inhibitory neurotransmitters

7965-576: Is important, and differs from the sum of its parts. Psychologists in Germany, Denmark, Austria, England, and the United States soon followed Wundt in setting up laboratories. G. Stanley Hall , an American who studied with Wundt, founded a psychology lab that became internationally influential. The lab was located at Johns Hopkins University . Hall, in turn, trained Yujiro Motora , who brought experimental psychology, emphasizing psychophysics, to

8142-478: Is not absolute. Rather, it depends on the class of chemical receptors present on the postsynaptic neuron. In principle, a single neuron, releasing a single neurotransmitter, can have excitatory effects on some targets, inhibitory effects on others, and modulatory effects on others still. For example, photoreceptor cells in the retina constantly release the neurotransmitter glutamate in the absence of light. So-called OFF bipolar cells are, like most neurons, excited by

8319-413: Is not an objective science. Skeptics have suggested that personality, thinking, and emotion cannot be directly measured and are often inferred from subjective self-reports, which may be problematic. Experimental psychologists have devised a variety of ways to indirectly measure these elusive phenomenological entities. Divisions still exist within the field, with some psychologists more oriented towards

8496-454: Is often thought of as a new method (most of the technology is relatively recent), the underlying principle goes back as far as 1878 when blood flow was first associated with brain function. Angelo Mosso , an Italian psychologist of the 19th century, had monitored the pulsations of the adult brain through neurosurgically created bony defects in the skulls of patients. He noted that when the subjects engaged in tasks such as mathematical calculations

8673-459: Is represented in the brain by neurons. The main goal of studying neural coding is to characterize the relationship between the stimulus and the individual or ensemble neuronal responses and the relationships among the electrical activities of the neurons within the ensemble. It is thought that neurons can encode both digital and analog information. The conduction of nerve impulses is an example of an all-or-none response. In other words, if

8850-506: Is that a large part of both human and lower-animal behavior is learned. A principle associated with behavioral research is that the mechanisms involved in learning apply to humans and non-human animals. Behavioral researchers have developed a treatment known as behavior modification , which is used to help individuals replace undesirable behaviors with desirable ones. Early behavioral researchers studied stimulus–response pairings, now known as classical conditioning . They demonstrated that when

9027-405: Is the scientific study of mind and behavior . Its subject matter includes the behavior of humans and nonhumans, both conscious and unconscious phenomena, and mental processes such as thoughts , feelings , and motives . Psychology is an academic discipline of immense scope, crossing the boundaries between the natural and social sciences . Biological psychologists seek an understanding of

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9204-432: Is transferred to the axon, which fires. If the pressure is steady, the stimulus ends; thus, these neurons typically respond with a transient depolarization during the initial deformation and again when the pressure is removed, which causes the corpuscle to change shape again. Other types of adaptation are important in extending the function of several other neurons. The German anatomist Heinrich Wilhelm Waldeyer introduced

9381-643: Is used extensively by the Allen Institute for Brain Science . In 2023, a comprehensive cell atlas of the adult, and developing human brain at the transcriptional, epigenetic, and functional levels was created through an international collaboration of researchers using the most cutting-edge molecular biology approaches. Neurons communicate with each other via synapses , where either the axon terminal of one cell contacts another neuron's dendrite, soma, or, less commonly, axon. Neurons such as Purkinje cells in

9558-529: The Gemeinschaft ." Psychologists were to provide Seelenführung [lit., soul guidance], the leadership of the mind, to integrate people into the new vision of a German community. Harald Schultz-Hencke melded psychology with the Nazi theory of biology and racial origins, criticizing psychoanalysis as a study of the weak and deformed. Johannes Heinrich Schultz , a German psychologist recognized for developing

9735-475: The Upanishads and other Vedic texts that formed the foundations of Hinduism was the distinction between a person's transient mundane self and their eternal, unchanging soul . Divergent Hindu doctrines and Buddhism have challenged this hierarchy of selves, but have all emphasized the importance of reaching higher awareness. Yoga encompasses a range of techniques used in pursuit of this goal. Theosophy ,

9912-625: The Brain Prize "for their pioneering research on higher brain mechanisms underpinning such complex human functions as literacy, numeracy, motivated behaviour and social cognition, and for their efforts to understand cognitive and behavioural disorders". Brenda Milner , Marcus Raichle and John O'Keefe received the Kavli Prize in Neuroscience "for the discovery of specialized brain networks for memory and cognition" and O'Keefe shared

10089-530: The Ebers Papyrus mentioned depression and thought disorders. Historians note that Greek philosophers, including Thales , Plato , and Aristotle (especially in his De Anima treatise), addressed the workings of the mind. As early as the 4th century BC, the Greek physician Hippocrates theorized that mental disorders had physical rather than supernatural causes. In 387 BCE, Plato suggested that

10266-524: The Imperial University of Tokyo . Wundt's assistant, Hugo Münsterberg , taught psychology at Harvard to students such as Narendra Nath Sen Gupta —who, in 1905, founded a psychology department and laboratory at the University of Calcutta . Wundt's students Walter Dill Scott , Lightner Witmer , and James McKeen Cattell worked on developing tests of mental ability. Cattell, who also studied with eugenicist Francis Galton , went on to found

10443-584: The International Journal of Psychology . IAAP and IUPsyS agreed in 1976 each to hold a congress every four years, on a staggered basis. IUPsyS recognizes 66 national psychology associations and at least 15 others exist. The American Psychological Association is the oldest and largest. Its membership has increased from 5,000 in 1945 to 100,000 in the present day. The APA includes 54 divisions , which since 1960 have steadily proliferated to include more specialties. Some of these divisions, such as

10620-581: The Nobel Prize in Physiology or Medicine in the same year with May-Britt Moser and Edvard Moser "for their discoveries of cells that constitute a positioning system in the brain". In 2017, Wolfram Schultz , Peter Dayan and Ray Dolan were awarded the Brain Prize "for their multidisciplinary analysis of brain mechanisms that link learning to reward, which has far-reaching implications for

10797-629: The Psychological Corporation . Witmer focused on the mental testing of children; Scott, on employee selection. Another student of Wundt, the Englishman Edward Titchener , created the psychology program at Cornell University and advanced " structuralist " psychology. The idea behind structuralism was to analyze and classify different aspects of the mind, primarily through the method of introspection . William James, John Dewey , and Harvey Carr advanced

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10974-804: The Society for the Psychological Study of Social Issues and the American Psychology–Law Society , began as autonomous groups. The Interamerican Psychological Society , founded in 1951, aspires to promote psychology across the Western Hemisphere. It holds the Interamerican Congress of Psychology and had 1,000 members in year 2000. The European Federation of Professional Psychology Associations, founded in 1981, represents 30 national associations with

11151-582: The Weber–Fechner law . Fechner's 1860 Elements of Psychophysics challenged Kant's negative view with regard to conducting quantitative research on the mind. Fechner's achievement was to show that "mental processes could not only be given numerical magnitudes, but also that these could be measured by experimental methods." In Heidelberg, Hermann von Helmholtz conducted parallel research on sensory perception, and trained physiologist Wilhelm Wundt . Wundt, in turn, came to Leipzig University, where he established

11328-461: The cerebellum (brain) in rabbits and pigeons affected their sense of muscular coordination, and that all cognitive functions were disrupted in pigeons when the cerebral hemispheres were removed. From this he concluded that the cerebral cortex , cerebellum , and brainstem functioned together as a whole. His approach has been criticised on the basis that the tests were not sensitive enough to notice selective deficits had they been present. Perhaps

11505-402: The cognitive revolution were major turning points in the creation of cognitive neuroscience as a field, bringing together ideas and techniques that enabled researchers to make more links between behavior and its neural substrates. Philosophers have always been interested in the mind: "the idea that explaining a phenomenon involves understanding the mechanism responsible for it has deep roots in

11682-399: The emergent properties of brains, linking the discipline to neuroscience . As social scientists, psychologists aim to understand the behavior of individuals and groups. A professional practitioner or researcher involved in the discipline is called a psychologist . Some psychologists can also be classified as behavioral or cognitive scientists . Some psychologists attempt to understand

11859-472: The glial cells that give them structural and metabolic support. The nervous system is made up of the central nervous system , which includes the brain and spinal cord , and the peripheral nervous system , which includes the autonomic , enteric and somatic nervous systems . In vertebrates, the majority of neurons belong to the central nervous system , but some reside in peripheral ganglia , and many sensory neurons are situated in sensory organs such as

12036-402: The retina and cochlea . Axons may bundle into nerve fascicles that make up the nerves in the peripheral nervous system (like strands of wire that make up a cable). In the central nervous system bundles of axons are called nerve tracts . Neurons are highly specialized for the processing and transmission of cellular signals. Given the diversity of functions performed in different parts of

12213-434: The societal norms and roles they are assigned. As she states in her article, "Variability as related to sex differences in achievement: A Critique", the largest problem women have is the social order that was built due to the assumption women have less interests and abilities than men. To further prove her point, she completed another experiment with infants who have not been influenced by the environment of social norms, like

12390-686: The squid giant axon could be used to study neuronal electrical properties. It is larger than but similar to human neurons, making it easier to study. By inserting electrodes into the squid giant axons, accurate measurements were made of the membrane potential . The cell membrane of the axon and soma contain voltage-gated ion channels that allow the neuron to generate and propagate an electrical signal (an action potential). Some neurons also generate subthreshold membrane potential oscillations . These signals are generated and propagated by charge-carrying ions including sodium (Na ), potassium (K ), chloride (Cl ), and calcium (Ca ) . Several stimuli can activate

12567-444: The synapse to another cell. Neurons may lack dendrites or have no axons. The term neurite is used to describe either a dendrite or an axon, particularly when the cell is undifferentiated . Most neurons receive signals via the dendrites and soma and send out signals down the axon. At the majority of synapses, signals cross from the axon of one neuron to the dendrite of another. However, synapses can connect an axon to another axon or

12744-409: The tubulin of microtubules . Class III β-tubulin is found almost exclusively in neurons. Actin is predominately found at the tips of axons and dendrites during neuronal development. There the actin dynamics can be modulated via an interplay with microtubule. There are different internal structural characteristics between axons and dendrites. Typical axons seldom contain ribosomes , except some in

12921-509: The 1870s, when in France Paul Broca traced production of speech to the left frontal gyrus, thereby also demonstrating hemispheric lateralization of brain function. Soon after, Carl Wernicke identified a related area necessary for the understanding of speech. The contemporary field of behavioral neuroscience focuses on the physical basis of behavior. Behaviorial neuroscientists use animal models, often relying on rats, to study

13098-634: The 1910s and 1920s, eugenics became a standard topic in psychology classes. In contrast to the US, in the UK psychology was met with antagonism by the scientific and medical establishments, and up until 1939, there were only six psychology chairs in universities in England. During World War II and the Cold War, the U.S. military and intelligence agencies established themselves as leading funders of psychology by way of

13275-469: The 1940s. These tests, called the doll tests , asked young children to choose between identical dolls whose only difference was race, and they found that the majority of the children preferred the white dolls and attributed positive traits to them. Repeated over and over again, these tests helped to determine the negative effects of racial discrimination and segregation on black children's self-image and development. In 1954, this research would help decide

13452-496: The 1980s, interaction between neuroscience and cognitive science was scarce. Cognitive neuroscience began to integrate the newly laid theoretical ground in cognitive science, that emerged between the 1950s and 1960s, with approaches in experimental psychology, neuropsychology and neuroscience. (Neuroscience was not established as a unified discipline until 1971). In the late 1970s, neuroscientist Michael S. Gazzaniga and cognitive psychologist George A. Miller were said to have first coined

13629-582: The 20th century further diversified the field of psychology, with women of color reaching new milestones. In 1962, Martha Bernal became the first Latina woman to get a Ph.D. in psychology. In 1969, Marigold Linton , the first Native American woman to get a Ph.D. in psychology, founded the National Indian Education Association . She was also a founding member of the Society for Advancement of Chicanos and Native Americans in Science . In 1971, The Network of Indian Psychologists

13806-471: The APA's Distinguished Career Contribution to Research Award from the Society for the Psychological Study of Culture Ethnicity, and Race for her research on suicide prevention . She was the first person to lead an intervention for Native American children and adolescents that utilized evidence-based suicide prevention. She has spent her career dedicated to aiding racial and ethnic minority youth cope with cultural adjustment and pressures. Dr. Shari Miles-Cohen,

13983-453: The Army's Project Camelot , the "Manhattan Project" of social science , an effort which enlisted psychologists and anthropologists to analyze the plans and policies of foreign countries for strategic purposes. In Germany after World War I, psychology held institutional power through the military, which was subsequently expanded along with the rest of the military during Nazi Germany . Under

14160-518: The Greek word psyche , for spirit or soul . The latter part of the word psychology derives from -λογία -logia , which means "study" or "research". The word psychology was first used in the Renaissance. In its Latin form psychiologia , it was first employed by the Croatian humanist and Latinist Marko Marulić in his book Psichiologia de ratione animae humanae ( Psychology, on

14337-485: The History of Philosophy from atomic theories in 5th century B.C. to its rebirth in the 17th and 18th century in the works of Galileo, Descartes, and Boyle. Among others, it's Descartes' idea that machines humans build could work as models of scientific explanation." For example, Aristotle thought the brain was the body's cooling system and the capacity for intelligence was located in the heart . It has been suggested that

14514-548: The Institute of Psychology. Because most leading psychologists were educated in the United States, the first concern of the academy was the re-education of these psychologists in the Soviet doctrines. Child psychology and pedagogy for the purpose of a nationally cohesive education remained a central goal of the discipline. Women in the early 1900s started to make key findings within the world of psychology. In 1923, Anna Freud ,

14691-767: The Nature of the Human Soul ) in the decade 1510–1520 The earliest known reference to the word psychology in English was by Steven Blankaart in 1694 in The Physical Dictionary . The dictionary refers to " Anatomy , which treats the Body, and Psychology, which treats of the Soul." Ψ ( psi ) , the first letter of the Greek word psyche from which the term psychology is derived, is commonly associated with

14868-469: The Prussian state established psychology as a mandatory discipline in its rapidly expanding and highly influential educational system . However, this discipline did not yet embrace experimentation. In England, early psychology involved phrenology and the response to social problems including alcoholism, violence, and the country's crowded "lunatic" asylums. Philosopher John Stuart Mill believed that

15045-633: The Rockefeller Foundation, Mitscherlich established the first clinical psychosomatic medicine division at Heidelberg University. In 1970, psychology was integrated into the required studies of medical students. After the Russian Revolution , the Bolsheviks promoted psychology as a way to engineer the "New Man" of socialism. Consequently, university psychology departments trained large numbers of students in psychology. At

15222-491: The Soviet Union and inspired followers to use his methods on humans. In the United States, Edward Lee Thorndike initiated " connectionist " studies by trapping animals in "puzzle boxes" and rewarding them for escaping. Thorndike wrote in 1911, "There can be no moral warrant for studying man's nature unless the study will enable us to control his acts." From 1910 to 1913 the American Psychological Association went through

15399-402: The Soviet Union. Stalinist purges took a heavy toll and instilled a climate of fear in the profession, as elsewhere in Soviet society. Following World War II, Jewish psychologists past and present, including Lev Vygotsky , A.R. Luria , and Aron Zalkind, were denounced; Ivan Pavlov (posthumously) and Stalin himself were celebrated as heroes of Soviet psychology. Soviet academics experienced

15576-614: The U.S.'s entry into World War I. A standing committee headed by Robert Yerkes administered mental tests (" Army Alpha " and " Army Beta ") to almost 1.8 million soldiers. Subsequently, the Rockefeller family , via the Social Science Research Council , began to provide funding for behavioral research. Rockefeller charities funded the National Committee on Mental Hygiene, which disseminated

15753-700: The World's Fair celebrating the centennial of the French Revolution. William James was one of three Americans among the 400 attendees. The American Psychological Association (APA) was founded soon after, in 1892. The International Congress continued to be held at different locations in Europe and with wide international participation. The Sixth Congress, held in Geneva in 1909, included presentations in Russian, Chinese, and Japanese, as well as Esperanto . After

15930-462: The ability to generate electric signals first appeared in evolution some 700 to 800 million years ago, during the Tonian period. Predecessors of neurons were the peptidergic secretory cells. They eventually gained new gene modules which enabled cells to create post-synaptic scaffolds and ion channels that generate fast electrical signals. The ability to generate electric signals was a key innovation in

16107-600: The accomplishments of women of color in psychology. She is well known for co-editing Eliminating Inequities for Women with Disabilities: An Agenda for Health and Wellness (published in 2016), her article published in the Women's Reproductive Health Journal about women of color's struggle with pregnancy and postpartum (Published in 2018), and co-authoring the "APA Handbook of the Psychology of Women" (published in 2019). In 1920, Édouard Claparède and Pierre Bovet created

16284-456: The adult brain may regenerate functional neurons throughout the life of an organism (see neurogenesis ). Astrocytes are star-shaped glial cells that have been observed to turn into neurons by virtue of their stem cell-like characteristic of pluripotency . Like all animal cells, the cell body of every neuron is enclosed by a plasma membrane , a bilayer of lipid molecules with many types of protein structures embedded in it. A lipid bilayer

16461-406: The adult male getting more opportunities than women. She found no difference between infants besides size. After this research proved the original hypothesis wrong, Hollingworth was able to show there is no difference between the physiological and psychological traits of men and women, and women are not impaired during menstruation . The first half of the 1900s was filled with new theories and it

16638-620: The application of biological principles to the study of physiological and genetic mechanisms underlying behavior in humans and other animals. The allied field of comparative psychology is the scientific study of the behavior and mental processes of non-human animals. A leading question in behavioral neuroscience has been whether and how mental functions are localized in the brain . From Phineas Gage to H.M. and Clive Wearing , individual people with mental deficits traceable to physical brain damage have inspired new discoveries in this area. Modern behavioral neuroscience could be said to originate in

16815-625: The armed forces and in the new Office of Strategic Services intelligence agency. University of Michigan psychologist Dorwin Cartwright reported that university researchers began large-scale propaganda research in 1939–1941. He observed that "the last few months of the war saw a social psychologist become chiefly responsible for determining the week-by-week-propaganda policy for the United States Government." Cartwright also wrote that psychologists had significant roles in managing

16992-429: The axon and activates synaptic connections as it reaches them. Synaptic signals may be excitatory or inhibitory , increasing or reducing the net voltage that reaches the soma. In most cases, neurons are generated by neural stem cells during brain development and childhood. Neurogenesis largely ceases during adulthood in most areas of the brain. Neurons are the primary components of the nervous system , along with

17169-584: The axon terminal, it opens voltage-gated calcium channels , allowing calcium ions to enter the terminal. Calcium causes synaptic vesicles filled with neurotransmitter molecules to fuse with the membrane, releasing their contents into the synaptic cleft. The neurotransmitters diffuse across the synaptic cleft and activate receptors on the postsynaptic neuron. High cytosolic calcium in the axon terminal triggers mitochondrial calcium uptake, which, in turn, activates mitochondrial energy metabolism to produce ATP to support continuous neurotransmission. An autapse

17346-517: The behavior of animals. Hitzig and Fritsch ran an electric current through the cerebral cortex of a dog, causing different muscles to contract depending on which areas of the brain were electrically stimulated. This led to the proposition that individual functions are localized to specific areas of the brain rather than the cerebrum as a whole, as the aggregate field view suggests. Brodmann was also an important figure in brain mapping; his experiments based on Franz Nissl's tissue staining techniques divided

17523-541: The belief women are mentally and physically impaired during menstruation , impacted women's rights because employers were less likely to hire them due to the belief they would be incapable of working for 1 week a month. Leta Stetter Hollingworth wanted to prove this hypothesis and Edward L. Thorndike's theory, that women have lesser psychological and physical traits than men and were simply mediocre, incorrect. Hollingworth worked to prove differences were not from male genetic superiority, but from culture. She also included

17700-573: The brain advanced during the Qing dynasty with the work of Western-educated Fang Yizhi (1611–1671), Liu Zhi (1660–1730), and Wang Qingren (1768–1831). Wang Qingren emphasized the importance of the brain as the center of the nervous system, linked mental disorder with brain diseases, investigated the causes of dreams and insomnia , and advanced a theory of hemispheric lateralization in brain function. Influenced by Hinduism , Indian philosophy explored distinctions in types of awareness. A central idea of

17877-452: The brain and the nervous system are the center of the mind and emotion. Psychology , a major contributing field to cognitive neuroscience, emerged from philosophical reasoning about the mind. One of the predecessors to cognitive neuroscience was phrenology , a pseudoscientific approach that claimed that behavior could be determined by the shape of the scalp . In the early 19th century, Franz Joseph Gall and J. G. Spurzheim believed that

18054-527: The brain by stimulating the cortices of patients during surgery. The work of Sperry and Gazzaniga on split brain patients in the 1950s was also instrumental in the progress of the field. The term cognitive neuroscience itself was coined by Gazzaniga and cognitive psychologist George Armitage Miller while sharing a taxi in 1976. New brain mapping technology, particularly fMRI and PET , allowed researchers to investigate experimental strategies of cognitive psychology by observing brain function. Although this

18231-559: The brain include places in Wernicke's area , the left side of the temporal lobe , and Broca's area close to the frontal lobe. Also, cognitive abilities based on brain development are studied and examined under the subfield of developmental cognitive neuroscience . This shows brain development over time, analyzing differences and concocting possible reasons for those differences. Theoretical approaches include computational neuroscience and cognitive psychology . Cognitive neuroscience

18408-593: The brain into fifty-two areas. At the start of the 20th century, attitudes in America were characterized by pragmatism, which led to a preference for behaviorism as the primary approach in psychology . J.B. Watson was a key figure with his stimulus-response approach. By conducting experiments on animals he was aiming to be able to predict and control behavior. Behaviorism eventually failed because it could not provide realistic psychology of human action and thought – it focused primarily on stimulus-response associations at

18585-401: The brain is where mental processes take place, and in 335 BCE Aristotle suggested that it was the heart. In China, psychological understanding grew from the philosophical works of Laozi and Confucius , and later from the doctrines of Buddhism . This body of knowledge involves insights drawn from introspection and observation, as well as techniques for focused thinking and acting. It frames

18762-462: The brain rather than on what the characteristics of the abilities were and how to measure them. Studies performed in Europe, such as those of John Hughlings Jackson , supported this view. Jackson studied patients with brain damage , particularly those with epilepsy . He discovered that the epileptic patients often made the same clonic and tonic movements of muscle during their seizures, leading Jackson to believe that they must be caused by activity in

18939-536: The brain that had less myelin and discovering that neurons were discrete cells. Cajal also discovered that cells transmit electrical signals down the neuron in one direction only. Both Golgi and Cajal were awarded a Nobel Prize in Physiology or Medicine in 1906 for this work on the neuron doctrine. Several findings in the 20th century continued to advance the field, such as the discovery of ocular dominance columns , recording of single nerve cells in animals, and coordination of eye and head movements. Experimental psychology

19116-438: The central nervous system and Schwann cells in the peripheral nervous system. The sheath enables action potentials to travel faster than in unmyelinated axons of the same diameter, whilst using less energy. The myelin sheath in peripheral nerves normally runs along the axon in sections about 1 mm long, punctuated by unsheathed nodes of Ranvier , which contain a high density of voltage-gated ion channels. Multiple sclerosis

19293-420: The central nervous system are typically only about one micrometer thick, while some in the peripheral nervous system are much thicker. The soma is usually about 10–25 micrometers in diameter and often is not much larger than the cell nucleus it contains. The longest axon of a human motor neuron can be over a meter long, reaching from the base of the spine to the toes. Sensory neurons can have axons that run from

19470-548: The cerebellum can have over 1000 dendritic branches, making connections with tens of thousands of other cells; other neurons, such as the magnocellular neurons of the supraoptic nucleus , have only one or two dendrites, each of which receives thousands of synapses. Synapses can be excitatory or inhibitory, either increasing or decreasing activity in the target neuron, respectively. Some neurons also communicate via electrical synapses, which are direct, electrically conductive junctions between cells. When an action potential reaches

19647-549: The completion of training, positions were made available for those students at schools, workplaces, cultural institutions, and in the military. The Russian state emphasized pedology and the study of child development. Lev Vygotsky became prominent in the field of child development. The Bolsheviks also promoted free love and embraced the doctrine of psychoanalysis as an antidote to sexual repression. Although pedology and intelligence testing fell out of favor in 1936, psychology maintained its privileged position as an instrument of

19824-667: The concept of mental illness and lobbied for applying ideas from psychology to child rearing. Through the Bureau of Social Hygiene and later funding of Alfred Kinsey , Rockefeller foundations helped establish research on sexuality in the U.S. Under the influence of the Carnegie-funded Eugenics Record Office , the Draper-funded Pioneer Fund , and other institutions, the eugenics movement also influenced American psychology. In

20001-432: The concept of women's impairment during menstruation in her research. She recorded both women and men performances on tasks (cognitive, perceptual, and motor) for three months. No evidence was found of decreased performance due to a woman's menstrual cycle. She also challenged the belief intelligence is inherited and women here are intellectually inferior to men. She stated that women do not reach positions of power due to

20178-405: The creation of phrenometers, which measured the bumps on a human subject's head. While phrenology remained a fixture at fairs and carnivals, it did not enjoy wide acceptance within the scientific community. The major criticism of phrenology is that researchers were not able to test theories empirically. The localizationist view was concerned with mental abilities being localized to specific areas of

20355-405: The daughter of Sigmund Freud , built on her father's work using different defense mechanisms (denial, repression, and suppression) to psychoanalyze children. She believed that once a child reached the latency period , child analysis could be used as a mode of therapy . She stated it is important focus on the child's environment, support their development, and prevent neurosis . She believed

20532-451: The difference between conscious and unconscious awareness is only a matter of degree. Christian Wolff identified psychology as its own science, writing Psychologia Empirica in 1732 and Psychologia Rationalis in 1734. Immanuel Kant advanced the idea of anthropology as a discipline, with psychology an important subdivision. Kant, however, explicitly rejected the idea of an experimental psychology , writing that "the empirical doctrine of

20709-692: The direction of Hermann Göring 's cousin Matthias Göring , the Berlin Psychoanalytic Institute was renamed the Göring Institute. Freudian psychoanalysts were expelled and persecuted under the anti-Jewish policies of the Nazi Party , and all psychologists had to distance themselves from Freud and Adler , founders of psychoanalysis who were also Jewish. The Göring Institute was well-financed throughout

20886-596: The domestic economy. The Army rolled out its new General Classification Test to assess the ability of millions of soldiers. The Army also engaged in large-scale psychological research of troop morale and mental health . In the 1950s, the Rockefeller Foundation and Ford Foundation collaborated with the Central Intelligence Agency (CIA) to fund research on psychological warfare . In 1965, public controversy called attention to

21063-465: The early 20th century, Wolfgang Kohler , Max Wertheimer , and Kurt Koffka co-founded the school of Gestalt psychology of Fritz Perls . The approach of Gestalt psychology is based upon the idea that individuals experience things as unified wholes. Rather than reducing thoughts and behavior into smaller component elements, as in structuralism, the Gestaltists maintained that whole of experience

21240-551: The environment and hormones released from other parts of the organism, which could be influenced more or less directly by neurons. This also applies to neurotrophins such as BDNF . The gut microbiome is also connected with the brain. Neurons also communicate with microglia , the brain's main immune cells via specialized contact sites, called "somatic junctions". These connections enable microglia to constantly monitor and regulate neuronal functions, and exert neuroprotection when needed. In 1937 John Zachary Young suggested that

21417-612: The establishment of university psychology departments and journals, and the establishment of groups including the Chinese Association of Psychological Testing (1930) and the Chinese Psychological Society (1937). Chinese psychologists were encouraged to focus on education and language learning. Chinese psychologists were drawn to the idea that education would enable modernization. John Dewey, who lectured to Chinese audiences between 1919 and 1921, had

21594-477: The evolution of the nervous system. Neurons are typically classified into three types based on their function. Sensory neurons respond to stimuli such as touch, sound, or light that affect the cells of the sensory organs , and they send signals to the spinal cord or brain . Motor neurons receive signals from the brain and spinal cord to control everything from muscle contractions to glandular output . Interneurons connect neurons to other neurons within

21771-477: The excitation from the OFF bipolar cells, silencing them. It is possible to identify the type of inhibitory effect a presynaptic neuron will have on a postsynaptic neuron, based on the proteins the presynaptic neuron expresses. Parvalbumin -expressing neurons typically dampen the output signal of the postsynaptic neuron in the visual cortex , whereas somatostatin -expressing neurons typically block dendritic inputs to

21948-495: The expense of explaining phenomena like thought and imagination. This led to what is often termed as the "cognitive revolution". In the early 20th century, Santiago Ramón y Cajal and Camillo Golgi began working on the structure of the neuron. Golgi developed a silver staining method that could entirely stain several cells in a particular area, leading him to believe that neurons were directly connected with each other in one cytoplasm. Cajal challenged this view after staining areas of

22125-403: The field of psychology. In 1890, William James defined psychology as "the science of mental life, both of its phenomena and their conditions." This definition enjoyed widespread currency for decades. However, this meaning was contested, notably by radical behaviorists such as John B. Watson , who in 1913 asserted that the discipline is a natural science , the theoretical goal of which "is

22302-741: The field, female psychologists in the U.S. formed the National Council of Women Psychologists in 1941. This organization became the International Council of Women Psychologists after World War II and the International Council of Psychologists in 1959. Several associations including the Association of Black Psychologists and the Asian American Psychological Association have arisen to promote the inclusion of non-European racial groups in

22479-507: The findings at this meeting in his 1967 book Cognitive Psychology . The term "psychology" had been waning in the 1950s and 1960s, causing the field to be referred to as "cognitive science". Behaviorists such as Miller began to focus on the representation of language rather than general behavior. David Marr concluded that one should understand any cognitive process at three levels of analysis. These levels include computational, algorithmic/representational, and physical levels of analysis. Before

22656-456: The first person to believe otherwise was the Roman physician Galen in the second century AD, who declared that the brain was the source of mental activity, although this has also been accredited to Alcmaeon . However, Galen believed that personality and emotion were not generated by the brain, but rather by other organs. Andreas Vesalius , an anatomist and physician, was the first to believe that

22833-405: The first serious attempts to localize mental functions to specific locations in the brain was by Broca and Wernicke . This was mostly achieved by studying the effects of injuries to different parts of the brain on psychological functions. In 1861, French neurologist Paul Broca came across a man with a disability who was able to understand the language but unable to speak. The man could only produce

23010-639: The human brain was localized into approximately 35 different sections. In his book, The Anatomy and Physiology of the Nervous System in General, and of the Brain in Particular, Gall claimed that a larger bump in one of these areas meant that that area of the brain was used more frequently by that person. This theory gained significant public attention, leading to the publication of phrenology journals and

23187-503: The human mind was open to scientific investigation, even if the science is in some ways inexact. Mill proposed a "mental chemistry " in which elementary thoughts could combine into ideas of greater complexity. Gustav Fechner began conducting psychophysics research in Leipzig in the 1830s. He articulated the principle that human perception of a stimulus varies logarithmically according to its intensity. The principle became known as

23364-665: The idea of functionalism , an expansive approach to psychology that underlined the Darwinian idea of a behavior's usefulness to the individual. In 1890, James wrote an influential book, The Principles of Psychology , which expanded on the structuralism. He memorably described " stream of consciousness ." James's ideas interested many American students in the emerging discipline. Dewey integrated psychology with societal concerns, most notably by promoting progressive education , inculcating moral values in children, and assimilating immigrants. A different strain of experimentalism, with

23541-486: The initial segment. Dendrites contain granular endoplasmic reticulum or ribosomes, in diminishing amounts as the distance from the cell body increases. Neurons vary in shape and size and can be classified by their morphology and function. The anatomist Camillo Golgi grouped neurons into two types; type I with long axons used to move signals over long distances and type II with short axons, which can often be confused with dendrites. Type I cells can be further classified by

23718-483: The landmark Brown v. Board of Education decision, leading to the end of legal segregation across the nation. Clark went on to be an influential figure in psychology, her work continuing to focus on minority youth. As the field of psychology developed throughout the latter half of the 20th century, women in the field advocated for their voices to be heard and their perspectives to be valued. Second-wave feminism did not miss psychology. An outspoken feminist in psychology

23895-418: The late nineteenth century enjoyed popularity (including the interest of scholars such as William James). Some people considered parapsychology to be part of "psychology". Parapsychology, hypnotism , and psychism were major topics at the early International Congresses. But students of these fields were eventually ostracized, and more or less banished from the Congress in 1900–1905. Parapsychology persisted for

24072-472: The localizationist view. Additionally, Aphasia is a learning disorder which was also discovered by Paul Broca. According to, Johns Hopkins School of Medicine, Aphasia is a language disorder caused by damage in a specific area of the brain that controls language expression and comprehension. This can often lead to the person speaking words with no sense known as "word salad" In 1870, German physicians Eduard Hitzig and Gustav Fritsch published their findings of

24249-411: The location of the soma. The basic morphology of type I neurons, represented by spinal motor neurons , consists of a cell body called the soma and a long thin axon covered by a myelin sheath . The dendritic tree wraps around the cell body and receives signals from other neurons. The end of the axon has branching axon terminals that release neurotransmitters into a gap called the synaptic cleft between

24426-399: The major influence, with Marxism–Leninism the leading social doctrine and Pavlovian conditioning the approved means of behavior change. Chinese psychologists elaborated on Lenin's model of a "reflective" consciousness, envisioning an "active consciousness" ( pinyin : tzu-chueh neng-tung-li ) able to transcend material conditions through hard work and ideological struggle. They developed

24603-402: The nervous system, there is a wide variety in their shape, size, and electrochemical properties. For instance, the soma of a neuron can vary from 4 to 100 micrometers in diameter. The accepted view of the neuron attributes dedicated functions to its various anatomical components; however, dendrites and axons often act in ways contrary to their so-called main function. Axons and dendrites in

24780-415: The neural, genetic, and cellular mechanisms that underlie behaviors involved in learning, memory, and fear responses. Cognitive neuroscientists , by using neural imaging tools, investigate the neural correlates of psychological processes in humans. Neuropsychologists conduct psychological assessments to determine how an individual's behavior and cognition are related to the brain. The biopsychosocial model

24957-406: The object maintains even pressure, the neurons stop firing. The neurons of the skin and muscles that are responsive to pressure and vibration have filtering accessory structures that aid their function. The pacinian corpuscle is one such structure. It has concentric layers like an onion, which form around the axon terminal. When pressure is applied and the corpuscle is deformed, mechanical stimulus

25134-564: The phosphate backbone of the ribosomal RNA. The cell body of a neuron is supported by a complex mesh of structural proteins called neurofilaments , which together with neurotubules (neuronal microtubules) are assembled into larger neurofibrils. Some neurons also contain pigment granules, such as neuromelanin (a brownish-black pigment that is byproduct of synthesis of catecholamines ), and lipofuscin (a yellowish-brown pigment), both of which accumulate with age. Other structural proteins that are important for neuronal function are actin and

25311-467: The postsynaptic neuron. Neurons have intrinsic electroresponsive properties like intrinsic transmembrane voltage oscillatory patterns. So neurons can be classified according to their electrophysiological characteristics: Neurotransmitters are chemical messengers passed from one neuron to another neuron or to a muscle cell or gland cell . Since 2012 there has been a push from the cellular and computational neuroscience community to come up with

25488-453: The prediction and control of behavior." Since James defined "psychology", the term more strongly implicates scientific experimentation. Folk psychology is the understanding of the mental states and behaviors of people held by ordinary people , as contrasted with psychology professionals' understanding. The ancient civilizations of Egypt, Greece, China, India, and Persia all engaged in the philosophical study of psychology. In Ancient Egypt

25665-616: The profession. The International Union of Psychological Science (IUPsyS) is the world federation of national psychological societies. The IUPsyS was founded in 1951 under the auspices of the United Nations Educational, Cultural and Scientific Organization (UNESCO) . Psychology departments have since proliferated around the world, based primarily on the Euro-American model. Since 1966, the Union has published

25842-494: The psychological laboratory that brought experimental psychology to the world. Wundt focused on breaking down mental processes into the most basic components, motivated in part by an analogy to recent advances in chemistry, and its successful investigation of the elements and structure of materials. Paul Flechsig and Emil Kraepelin soon created another influential laboratory at Leipzig, a psychology-related lab, that focused more on experimental psychiatry. James McKeen Cattell ,

26019-553: The pulsations of the brain increased locally. Such observations led Mosso to conclude that blood flow of the brain followed function. On September 11, 1956, a large-scale meeting of cognitivists took place at the Massachusetts Institute of Technology . George A. Miller presented his " The Magical Number Seven, Plus or Minus Two " paper while Noam Chomsky and Newell & Simon presented their findings on computer science . Ulric Neisser commented on many of

26196-474: The released glutamate. However, neighboring target neurons called ON bipolar cells are instead inhibited by glutamate, because they lack typical ionotropic glutamate receptors and instead express a class of inhibitory metabotropic glutamate receptors. When light is present, the photoreceptors cease releasing glutamate, which relieves the ON bipolar cells from inhibition, activating them; this simultaneously removes

26373-514: The results of natural selection or sexual selection over the course of human evolution. The history of the biological foundations of psychology includes evidence of racism. The idea of white supremacy and indeed the modern concept of race itself arose during the process of world conquest by Europeans. Carl von Linnaeus 's four-fold classification of humans classifies Europeans as intelligent and severe, Americans as contented and free, Asians as ritualistic, and Africans as lazy and capricious. Race

26550-550: The role of mental functions in individual and social behavior . Others explore the physiological and neurobiological processes that underlie cognitive functions and behaviors. Psychologists are involved in research on perception , cognition , attention , emotion , intelligence , subjective experiences , motivation , brain functioning , and personality . Psychologists' interests extend to interpersonal relationships , psychological resilience , family resilience , and other areas within social psychology . They also consider

26727-444: The same place in the brain every time. Jackson proposed that specific functions were localized to specific areas of the brain, which was critical to future understanding of the brain lobes . According to the aggregate field view, all areas of the brain participate in every mental function. Pierre Flourens , a French experimental psychologist, challenged the localizationist view by using animal experiments. He discovered that removing

26904-421: The same region of the brain or spinal cord. When multiple neurons are functionally connected together, they form what is called a neural circuit . A neuron contains all the structures of other cells such as a nucleus , mitochondria , and Golgi bodies but has additional unique structures such as an axon , and dendrites . The soma is a compact structure, and the axon and dendrites are filaments extruding from

27081-492: The second half of the 20th century continued to do research that had large-scale impacts on the field of psychology. Mary Ainsworth 's work centered around attachment theory . Building off fellow psychologist John Bowlby , Ainsworth spent years doing fieldwork to understand the development of mother-infant relationships. In doing this field research, Ainsworth developed the Strange Situation Procedure,

27258-512: The silver staining technique used to visualize nervous tissue under light microscopy. The neuron's place as the primary functional unit of the nervous system was first recognized in the late 19th century through the work of the Spanish anatomist Santiago Ramón y Cajal . To make the structure of individual neurons visible, Ramón y Cajal improved a silver staining process that had been developed by Camillo Golgi . The improved process involves

27435-399: The soma. Dendrites typically branch profusely and extend a few hundred micrometers from the soma. The axon leaves the soma at a swelling called the axon hillock and travels for as far as 1 meter in humans or more in other species. It branches but usually maintains a constant diameter. At the farthest tip of the axon's branches are axon terminals , where the neuron can transmit a signal across

27612-424: The soul can also never approach chemistry even as a systematic art of analysis or experimental doctrine, for in it the manifold of inner observation can be separated only by mere division in thought, and cannot then be held separate and recombined at will (but still less does another thinking subject suffer himself to be experimented upon to suit our purpose), and even observation by itself already changes and displaces

27789-545: The sound "tan". It was later discovered that the man had damage to an area of his left frontal lobe now known as Broca's area . Carl Wernicke, a German neurologist , found a patient who could speak fluently but non-sensibly. The patient had been the victim of a stroke , and could not understand spoken or written language. This patient had a lesion in the area where the left parietal and temporal lobes meet, now known as Wernicke's area . These cases, which suggested that lesions caused specific behavioral changes, strongly supported

27966-417: The stage for further research to be done in social psychology , especially in gender construction . Other women in the field also continued advocating for women in psychology, creating the Association for Women in Psychology to criticize how the field treated women. E. Kitsch Child , Phyllis Chesler , and Dorothy Riddle were some of the founding members of the organization in 1969. The latter half of

28143-621: The state of the observed object." In 1783, Ferdinand Ueberwasser (1752–1812) designated himself Professor of Empirical Psychology and Logic and gave lectures on scientific psychology, though these developments were soon overshadowed by the Napoleonic Wars . At the end of the Napoleonic era, Prussian authorities discontinued the Old University of Münster. Having consulted philosophers Hegel and Herbart , however, in 1825

28320-427: The technique of autogenic training , prominently advocated sterilization and euthanasia of men considered genetically undesirable, and devised techniques for facilitating this process. After the war, new institutions were created although some psychologists, because of their Nazi affiliation, were discredited. Alexander Mitscherlich founded a prominent applied psychoanalysis journal called Psyche . With funding from

28497-640: The term neuron in 1891, based on the ancient Greek νεῦρον neuron 'sinew, cord, nerve'. The word was adopted in French with the spelling neurone . That spelling was also used by many writers in English, but has now become rare in American usage and uncommon in British usage. Some previous works used nerve cell ( cellule nervose ), as adopted in Camillo Golgi 's 1873 paper on the discovery of

28674-439: The term "cognitive neuroscience." In the very late 20th century new technologies evolved that are now the mainstay of the methodology of cognitive neuroscience, including TMS (1985) and fMRI (1991). Earlier methods used in cognitive neuroscience include EEG (human EEG 1920) and MEG (1968). Occasionally cognitive neuroscientists utilize other brain imaging methods such as PET and SPECT . An upcoming technique in neuroscience

28851-422: The terminals and the dendrites of the next neuron. Most neurons can be anatomically characterized as: Some unique neuronal types can be identified according to their location in the nervous system and distinct shape. Some examples are: Afferent and efferent also refer generally to neurons that, respectively, bring information to or send information from the brain. A neuron affects other neurons by releasing

29028-489: The toes to the posterior column of the spinal cord, over 1.5 meters in adults. Giraffes have single axons several meters in length running along the entire length of their necks. Much of what is known about axonal function comes from studying the squid giant axon , an ideal experimental preparation because of its relatively immense size (0.5–1 millimeter thick, several centimeters long). Fully differentiated neurons are permanently postmitotic however, stem cells present in

29205-722: The unconscious mind. Research psychologists employ empirical methods to infer causal and correlational relationships between psychosocial variables . Some, but not all, clinical and counseling psychologists rely on symbolic interpretation . While psychological knowledge is often applied to the assessment and treatment of mental health problems, it is also directed towards understanding and solving problems in several spheres of human activity. By many accounts, psychology ultimately aims to benefit society. Many psychologists are involved in some kind of therapeutic role, practicing psychotherapy in clinical, counseling, or school settings. Other psychologists conduct scientific research on

29382-831: The understanding of human behaviour, including disorders of decision-making in conditions such as gambling, drug addiction, compulsive behaviour and schizophrenia"., Recently the focus of research had expanded from the localization of brain area(s) for specific functions in the adult brain using a single technology. Studies have been diverging in several different directions: exploring the interactions between different brain areas, using multiple technologies and approaches to understand brain functions, and using computational approaches. Advances in non-invasive functional neuroimaging and associated data analysis methods have also made it possible to use highly naturalistic stimuli and tasks such as feature films depicting social interactions in cognitive neuroscience studies. In recent years, there have been

29559-459: The unique experiences of individual humans, which cannot be understood only as data points within a larger population. Critics inside and outside the field have argued that mainstream psychology has become increasingly dominated by a "cult of empiricism", which limits the scope of research because investigators restrict themselves to methods derived from the physical sciences. Feminist critiques have argued that claims to scientific objectivity obscure

29736-548: The universe in term of a division of physical reality and mental reality as well as the interaction between the physical and the mental. Chinese philosophy also emphasized purifying the mind in order to increase virtue and power. An ancient text known as The Yellow Emperor's Classic of Internal Medicine identifies the brain as the nexus of wisdom and sensation, includes theories of personality based on yin–yang balance, and analyzes mental disorder in terms of physiological and social disequilibria. Chinese scholarship that focused on

29913-413: The values and agenda of (historically) mostly male researchers. Jean Grimshaw, for example, argues that mainstream psychological research has advanced a patriarchal agenda through its efforts to control behavior. Psychologists generally consider biology the substrate of thought and feeling, and therefore an important area of study. Behaviorial neuroscience, also known as biological psychology, involves

30090-404: The voltage difference across the membrane. Others are chemically gated, meaning that they can be switched between open and closed states by interactions with chemicals that diffuse through the extracellular fluid. The ion materials include sodium , potassium , chloride , and calcium . The interactions between ion channels and ion pumps produce a voltage difference across the membrane, typically

30267-506: The war with a mandate to create a "New German Psychotherapy." This psychotherapy aimed to align suitable Germans with the overall goals of the Reich. As described by one physician, "Despite the importance of analysis, spiritual guidance and the active cooperation of the patient represent the best way to overcome individual mental problems and to subordinate them to the requirements of the Volk and

30444-463: Was Naomi Weisstein , who was an accomplished researcher in psychology and neuroscience , and is perhaps best known for her paper, "Kirche, Kuche, Kinder as Scientific Law: Psychology Constructs the Female." Psychology Constructs the Female criticized the field of psychology for centering men and using biology too much to explain gender differences without taking into account social factors. Her work set

30621-607: Was a turning point for women's recognition within the field of psychology. In addition to the contributions made by Leta Stetter Hollingworth and Anna Freud , Mary Whiton Calkins invented the paired associates technique of studying memory and developed self-psychology . Karen Horney developed the concept of " womb envy " and neurotic needs. Psychoanalyst Melanie Klein impacted developmental psychology with her research of play therapy . These great discoveries and contributions were made during struggles of sexism , discrimination , and little recognition for their work. Women in

30798-488: Was also significant in the foundation of cognitive neuroscience. Some particularly important results were the demonstration that some tasks are accomplished via discrete processing stages, the study of attention, and the notion that behavioural data do not provide enough information by themselves to explain mental processes. As a result, some experimental psychologists began to investigate neural bases of behaviour. Wilder Penfield created maps of primary sensory and motor areas of

30975-467: Was also used to justify the construction of socially specific mental disorders such as drapetomania and dysaesthesia aethiopica —the behavior of uncooperative African slaves. After the creation of experimental psychology, "ethnical psychology" emerged as a subdiscipline, based on the assumption that studying primitive races would provide an important link between animal behavior and the psychology of more evolved humans. A tenet of behavioral research

31152-561: Was another woman in psychology that changed the field with her research. She was one of the first African-Americans to receive a doctoral degree in psychology from Columbia University , along with her husband, Kenneth Clark . Her master's thesis, "The Development of Consciousness in Negro Pre-School Children," argued that black children's self-esteem was negatively impacted by racial discrimination . She and her husband conduced research building off her thesis throughout

31329-802: Was established by Carolyn Attneave . Harriet McAdoo was appointed to the White House Conference on Families in 1979. Dr. Kay Redfield Jamison , named one of Time Magazine's "Best Doctors in the United States" is a lecturer, psychologist, and writer. She is known for her vast modern contributions to bipolar disorder and her books An Unquiet Mind (Published 1995) and Nothing Was the Same (Published in 2009). Having Bipolar Disorder herself, she has written several memoirs about her experience with suicidal thoughts , manic behaviors, depression , and other issues that arise from being Bipolar . Dr. Angela Neal-Barnett views psychology through

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