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45-615: In the spring of 1964 Hans Helmut Kornhuber (then docent and chief physician at the department of neurology, head Professor Richard Jung, university hospital Freiburg im Breisgau) and Lüder Deecke (his doctoral student) went for lunch to the 'Gasthaus zum Schwanen' at the foot of the Schlossberg hill in Freiburg. Sitting alone in the beautiful garden they discussed their frustration with the passive brain research prevailing worldwide and their desire to investigate self-initiated action of

90-581: A citation classic . He spent early interest in epistemology and brain function. He worked on the sensory systems /perception, conducting many experiments at Baltimore with Vernon Benjamin Mountcastle and his team on skin receptors , and also measuring the channel capacity of sensory systems (and consciousness ). He conducted his own research into new therapies with particular emphasis on multiple sclerosis , stroke , dementia , movement disorders , etc. He also made contributions for psychiatry, e.g.

135-504: A "duel" against a BCI ( brain–computer interface ) designed to predict their movements in real-time from observations of their EEG activity (the BP). They aimed to determine the exact time at which cancellation (veto) of movements was not possible anymore (the point of no return). The computer was trained to predict by means of the BP when a proband would move. The point of no return was at 200 ms before

180-504: A magnitude which makes it difficult to render them negligible even after hundreds of sweeps. In the case of eye movements eye muscle potentials have to be distinguished from cerebral potentials. In some cases animal experiments were necessary to clarify the origin of potentials such as the R-wave. Therefore, it took many years until some of the other laboratories were able to confirm the details of Kornhuber & Deecke's results. In addition to

225-521: Is even smaller, and the motor-potential which starts about fifty to sixty milliseconds before the onset of movement and has its maximum over the contralateral precentral hand area is still smaller. Thus, it takes great care to see these potentials: exact triggering by the real onset of movement is important, which is especially difficult preceding speech movements. Furthermore, artifacts due to head-, eye-, lid-, mouth-movements and respiration have to be eliminated before averaging because such artifacts may be of

270-531: Is mediated during movement preparation according to the Bereitschaftspotential amplitude. EEGs and EMGs are used in combination with Bayesian inference to construct Bayesian networks which attempt to predict general patterns of Motor Intent Neuron Action Potentials firing. Researchers attempting to develop non-intrusive brain–computer interfaces are interested in this, as are system analysis, operations research, and epistemology (e.g.

315-425: Is the contingent negative variation (CNV). The CNV also composes two waves; the initial wave (i.e., O wave) and the terminal wave (i.e., E wave). The terminal CNV has similar characteristics as the BP and many researchers have claimed that the BP and the terminal CNV are the same component. At least there is a consensus that both indicate a preparation of the brain for a following behavior. The Bereitschaftspotential

360-508: The Greek word νεῦρον meaning "nerve" and physiology meaning knowledge about the function of living systems (φύσις meaning "nature" and -λογία meaning "knowledge"). Neurophysiology has been a subject of study since as early as 4,000 B.C. In the early B.C. years, most studies were of different natural sedatives like alcohol and poppy plants. In 1700 B.C., the Edwin Smith surgical papyrus

405-672: The Order of Merit of the Federal Republic of Germany , and the German Society of Psychiatry honoured him for his research in the field of schizophrenia by awarding him the Kurt-Schneider prize. Scientific articles Books Neurophysiologist Neurophysiology is a branch of physiology and neuroscience that studies nervous system function rather than nervous system architecture. This area aids in

450-433: The cerebellum could affect motor movements. In 1776, Vincenzo Malacarne  [ it ] studied the cerebellum intensely, and published a book solely based on its function and appearance. In 1784, Félix Vicq-d'Azyr , discovered a black colored structure in the midbrain . In 1791 Samuel Thomas von Sömmerring alluded to this structure, calling it the substantia nigra . In the same year, Luigi Galvani described

495-628: The glutamate theory. He contributed to Otorhinolaryngology (hand book articles such as Physiology and Clinic of the Vestibular System ). Kornhuber also discovered the eye muscle field in the cerebellum . In 1967 Kornhuber received the Hans-Berger-Award of the German EEG society (DGKN) for his discovery of the cerebral foundations of will and purposeful actions (willingness to act). The Bárány Society honored him with

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540-691: The α-rhythm of the EEG; only by averaging, relating the electrical potentials to the onset of the movement it becomes apparent. Figure shows the typical slow shifts of the cortical DC potential, called Bereitschaftspotential, preceding volitional, rapid flexions of the right index finger. The vertical line indicates the instant of triggering t = 0 (first activity in the EMG of the agonist muscle). Recording positions are left precentral (L prec, C3), right precentral (R prec, C4), mid-parietal (Pz); these are unipolar recordings with linked ears as reference. The difference between

585-502: The BP in C3 and in C4 is displayed in the lowest graph (L/R prec). Superimposed are the results of eight experiments as obtained in the same subject (B.L.) on different days. see Deecke, L.; Grözinger, B.; Kornhuber H.H. (1976) Note that the BP has two components, the early one (BP1) lasting from about −1.2 to −0.5; the late component (BP2) from −0.5 to shortly before 0 sec. The pre-motion positivity

630-501: The Bereitschaftspotential is in brain–computer interface (BCI) applications; this signal feature can be identified from scalp recording (even from single-trial measurements) and interpreted for various uses, for example control of computer displays or control of peripheral motor units in spinal cord injuries. The most important BCI application is the 'mental' steering of artificial limbs in amputees. Hans Helmut Kornhuber Hans Helmut Kornhuber (24 February 1928 – 30 October 2009)

675-629: The English term psychology . In 1752, the Society of Friends created an asylum in Philadelphia , Pennsylvania. The asylum intended to give not only medical treatment to those mentally ill, but also provide with caretakers and comfortable living conditions. In 1755, Jean-Baptiste Le Roy began using electroconvulsive therapy for the mentally ill, a treatment still used today in specific cases. In 1760, Arne-Charles studied how different lesions in

720-400: The Freiburg laboratory. In the electroencephalogram (EEG) little is to be seen preceding actions, except of an inconstant diminution of the α- (or μ-) rhythm. The young researchers stored the electroencephalogram and electromyogram of self-initiated movements (fast finger flexions) on tape and analyzed the cerebral potentials preceding movements time-reversed with the start of the movement as

765-506: The Hallpike-Nylén-Award for his pioneering research on the vestibular system. He was awarded honorary membership by foreign oto-neurological societies. Universities awarded him as honorary professor and honorary doctor (University of Brussels). The Belgian neurophysiological society awarded Kornhuber an honorary membership. The Federal Republic of Germany honoured him for his efforts concerning the rehabilitation of patients with

810-542: The Smith predictor has been suggested in the discussion). In a series of neuroscience of free will experiments in the 1980s, Benjamin Libet studied the relationship between conscious experience of volition and the BP e.g. and found that the BP started about 0.35 sec earlier than the subject's reported conscious awareness that "now he or she feels the desire to make a movement." Libet concludes that we have no free will in

855-590: The achievement of a scientific break through in 1965 with the discovery of the Bereitschaftspotential (or readiness potential), together with his doctoral student Lüder Deecke . In 1965 Kornhuber (together with Lüder Deecke) discovered the Bereitschaftspotential , a brain potential in the EEG which precedes all our willed movements and actions. The publication, even though originally in German, became

900-436: The brain and the will. Consequently, they decided to look for cerebral potentials in man related to volitional acts and to take voluntary movement as their research paradigm. The possibility to do research on electrical brain potentials preceding voluntary movements came with the advent of the 'computer of average transients' (CAT computer), invented by Manfred Clynes , the first still simple instrument available at that time in

945-665: The brain, as opposed to the heart as Aristotle had theorized. The optic chiasm , which is crucial to the visual system, was discovered around 100 C.E. by Marinus. c.  1000 , Al-Zahrawi , living in Iberia , began to write about different surgical treatments for neurological disorders. In 1216, the first anatomy textbook in Europe, which included a description of the brain, was written by Mondino de Luzzi . In 1402, St Mary of Bethlehem Hospital (later known as Bedlam in Britain)

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990-423: The brain. In 1564, Giulio Cesare Aranzio discovered the hippocampus , naming it such due to its shape resemblance to a sea horse . In 1621, Robert Burton published The Anatomy of Melancholy , which looked at the loss of important characters in one's life as leading to depression. In 1649, René Descartes studied the pineal gland . He mistakenly believed that it was the "soul" of the brain, and believed it

1035-479: The cerebellum's role in equilibration to complete the Bell–Magendie law . In 1838, Theodor Schwann began studying white and grey matter in the brain, and discovered the myelin sheath . These cells, which cover the axons of the neurons in the brain, are named Schwann cells after him. In 1843 Carlo Matteucci and Emil du Bois-Reymond demonstrated that nerves transmit signals electrically. In 1848, Phineas Gage ,

1080-469: The classical neurophysiology patient, had his brain pierced by an iron tamping rod in a blasting accident. He became an excellent case study in the connection between the prefrontal cortex and behavior, decision making and consequences. In 1849, Hermann von Helmholtz studied the speed of frog nerve impulses while studying electricity in the body. While these are not all the developments in neurophysiology before 1849, these developments were significant to

1125-432: The diagnosis and monitoring of neurological diseases. Historically, the field has been dominated by electrophysiology , the electrical recording of neural activity, which includes electroencephalography and intracellular recording of the properties of single neurons, using methods such as the patch clamp , the voltage clamp , extracellular single-unit recording , and recording of local field potentials . However, since

1170-641: The early component of the Bereitschaftspotential (BP1 or BP early). The SMA has the starting function of the movement or action. The role of the SMA was further substantiated by Cunnington et al. 2003, showing that SMA proper and pre-SMA are active prior to volitional movement or action, as well as the cingulate motor area (CMA). This is now called ‘anterior mid-cingulate cortex (aMCC)’. Recently it has been shown by integrating simultaneously acquired EEG and fMRI that SMA and aMCC have strong reciprocal connections that act to sustain each other’s activity, and that this interaction

1215-540: The finger or eye movements as mentioned above, the BP has been recorded accompanying willful movements of the wrist, arm, shoulder, hip, knee, foot and toes. It was also recorded prior to speaking, writing and also swallowing. The magnetoencephalographic (MEG) equivalent of the Bereitschaftspotential (BP), 'Bereitschafts(magnetic)field' (BF), or readiness field (RF) was first recorded in Hal Weinberg's laboratory at Simon Fraser University Burnaby B.C. Canada in 1982. It

1260-507: The initiation of our movements; though, since subjects were able to prevent intended movement at the last moment, we do have the ability to veto these actions ("free won't"). These studies have provoked widespread debate. In 2016, a group around John-Dylan Haynes in Berlin (Germany) determined the time window after the BP in which an intended motion could possibly be cancelled upon command. The authors tested whether human volunteers could win

1305-417: The movement. However, even after that, when a pedal was already set in motion, the subjects were able to reschedule their action by not completing the already started behavior. The authors pointed out in their report that cancellation of self-initiated movements had already been reported by Libet in 1985. Thus, the new achievement was a more precise determination of the point of no return. An interesting use of

1350-407: The neuron is an electrochemical machine, it is difficult to isolate electrical events from the metabolic and molecular processes that cause them. Thus, neurophysiologists currently utilise tools from chemistry (calcium imaging), physics (functional magnetic resonance imaging, fMRI ), and molecular biology (site directed mutations) to examine brain activity. The word neurophysiology originates from

1395-410: The role of electricity in nerves of dissected frogs. In 1808, Franz Joseph Gall studied and published work on phrenology . Phrenology was the faulty science of looking at head shape to determine different aspects of personality and brain function. In 1811, Julien Jean César Legallois studied respiration in animal dissection and lesions and found the center of respiration in the medulla oblongata . In

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1440-401: The same year, Charles Bell finished work on what would later become known as the Bell–Magendie law , which compared functional differences between dorsal and ventral roots of the spinal cord . In 1822, Karl Friedrich Burdach distinguished between the lateral and medial geniculate bodies, as well as named the cingulate gyrus . In 1824, F. Magendie studied and produced the first evidence of

1485-500: The thesaurus of the American Psychological Association. The BP is an electrical sign of participation of the supplementary motor area (SMA) prior to volitional movement, which starts activity prior to the primary motor area. The BP has precipitated a worldwide discussion about free will (cf. the closing chapter in the book "The Bereitschaftspotential"). As said above, the activity of the SMA generates

1530-460: The time, however, was hostile to freedom in those years; it was believed that freedom is an illusion. The tradition of behaviourism and Freudism was deterministic. While will and volition were frequently leading concepts in psychological research papers before and after the first world war and even during the second war, after the end of the second world war this declined, and by the mid-sixties these key words completely disappeared and were abolished in

1575-488: The trigger, literally turning the tape over for analysis since they had no reversal playback or programmable computer. A potential preceding human voluntary movement was discovered and published in the same year. After detailed investigation and control experiments such as passive finger movements the Citation Classic with the term Bereitschaftspotential was published. The BP is ten to hundred times smaller than

1620-778: Was habilitated in 1963. He spent one and a half research years at the Johns Hopkins University , Baltimore. In 1967 he was appointed the chair of Neurology at the newly founded University of Ulm and there built the Neurological Hospital of the University of Ulm (until 1984 situated in Dietenbronn). In 1996 Kornhuber has been professor emeritus. One of his sons is the Psychiatrist and Psychotherapeut Johannes Kornhuber . Kornhuber saw

1665-560: Was a German neurologist and neurophysiologist . From 1949 on Kornhuber studied medicine at the universities of Munich , Göttingen , Freiburg , Basle and Heidelberg . In 1955 he was promoted to doctor of medicine in Heidelberg. In 1955 he married Ursula Heesch, they had five children. He absolved his clinical education at the Neurological University Hospital at the University of Freiburg, where he

1710-458: Was confirmed that the early component, BP 1 or BF1, respectively was generated by the supplementary motor area (SMA), including the pre-SMA, while the late component, BP2 or BF2, was generated by the primary motor area, MI. A very similar event-related potential (ERP) component had earlier been discovered by the British neurophysiologist William Grey Walter in 1962 and published in 1964. It

1755-400: Was devoted to neurological diseases, and discussed symptoms, as well as ideas from Galen and other Greek, Roman and Arabic authors. It also looked into the anatomy and specific functions of different areas. In 1550, Andreas Vesalius worked on a case of hydrocephalus , or fluid filling the brain. In the same year, Bartolomeo Eustachi studied the optic nerve , mainly focusing on its origin in

1800-474: Was received with great interest by the scientific community, as reflected by Sir John Eccles's comment: "There is a delightful parallel between these impressively simple experiments and the experiments of Galileo Galilei who investigated the laws of motion of the universe with metal balls on an inclined plane". The interest was even greater in psychology and philosophy because volition is traditionally associated with human freedom (cf. Kornhuber 1984). The spirit of

1845-405: Was the first hospital used exclusively for the mentally ill. In 1504, Leonardo da Vinci continued his study of the human body with a wax cast of the human ventricle system. In 1536, Nicolo Massa described the effects of different diseases, such as syphilis on the nervous system. He also noticed that the ventricular cavities were filled with cerebrospinal fluid . In 1542, the term physiology

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1890-490: Was used for the first time by a French physician named Jean Fernel , to explain bodily function in relation to the brain. In 1543, Andreas Vesalius wrote De humani corporis fabrica , which revolutionized the study of anatomy. In this book, he described the pineal gland and what he believed the function was, and was able to draw the corpus striatum which is made up of the basal ganglia and the internal capsule. In 1549, Jason Pratensis published De Cerebri Morbis . This book

1935-442: Was where intelligence was derived from. Hippocrates, as well as most ancient Greeks , believed that relaxation and a stress free environment was crucial in helping treat neurological disorders . In 280 B.C., Erasistratus of Chios theorized that there were divisions in vestibular processing in the brain, as well as deducing from observation that sensation was located there. In 177 Galen theorized that human thought occurred in

1980-402: Was where thoughts formed. In 1658, Johann Jakob Wepfer studied a patient in which he believed that a broken blood vessel had caused apoplexy , or a stroke . In 1749, David Hartley published Observations on Man , which focused on frame (neurology), duty ( moral psychology ) and expectations ( spirituality ) and how these integrated within one another. This text was also the first to use

2025-434: Was written. This papyrus was crucial in understanding how the ancient Egyptians understood the nervous system . This papyrus looked at different case studies about injuries to different parts of the body, most notably the head . Beginning around 460 B.C., Hippocrates began to study epilepsy , and theorized that it had its origins in the brain. Hippocrates also theorized that the brain was involved in sensation, and that it

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