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86<big><b>Scientific articles about &#8220;split-brain&#8221; experiments</b></big><br>
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92For some <a href="split_brain_experiments_videos.html">movies about
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100    <tr>
101      <td style="vertical-align: top;"> <a href="https://en.wikipedia.org/wiki/Split-brain">https://en.wikipedia.org/wiki/Split-brain</a><br>
102      </td>
103    </tr>
104    <tr>
105      <td style="vertical-align: top;"> Split-brain is a lay term to
106describe the result when the corpus callosum connecting the two
107hemispheres of the brain is severed to some degree. It is an
108association of symptoms produced by disruption of or interference with
109the connection between the hemispheres of the brain. The surgical
110operation to produce this condition (corpus callosotomy) involves
111transection of the corpus callosum, and is usually a last resort to
112treat refractory epilepsy. Initially, partial callosotomies are
113performed; if this operation does not succeed, a complete callosotomy
114is performed to mitigate the risk of accidental physical injury by
115reducing the severity and violence of epileptic seizures. Before using
116callosotomies, epilepsy is instead treated through pharmaceutical
117means. After surgery, neuropsychological assessments are often
118performed.<br>
119After the right and left brain are separated, each hemisphere will have
120its own separate perception, concepts, and impulses to act. Having two
121"brains" in one body can create some interesting dilemmas. When one
122split-brain patient dressed himself, he sometimes pulled his pants up
123with one hand (that side of his brain wanted to get dressed) and down
124with the other (this side didn't). Also, once he grabbed his wife with
125his left hand and shook her violently, so his right hand came to her
126aid and grabbed the aggressive left hand. However, such conflicts are
127actually rare. If a conflict arises, one hemisphere usually overrides
128the other.<br>
129When split-brain patients are shown an image only in their left visual
130field (the left half of what both eyes take in (see optic tract)), they
131cannot vocally name what they have seen. This can be explained in three
132steps: (1) The image seen in the left visual field is sent only to the
133right side of the brain; (2) For most people, the speech-control center
134is on the left side of the brain; and (3) Communication between the two
135sides of the brain is inhibited. Thus, the patient cannot say out loud
136the name of that which the right side of the brain is seeing. In the
137case that the speech-control center is on the right side of the brain,
138the image must now be presented to only the right visual field to
139achieve the same effect.<br>
140If a split-brain patient is touching a mysterious object with only the
141left hand, while also receiving no visual cues in the right visual
142field, the patient cannot say out loud the name of that which the right
143side of the brain is perceiving. This can be explained in three steps:
144(1) Each cerebral hemisphere of the primary somatosensory cortex only
145contains a tactile representation of the opposite (contralateral) side
146of the body; (2) For most humans, the speech-control center is on the
147left side of the brain; and (3) Communication between the two sides of
148the brain is inhibited. In the case that the speech-control center is
149on the right side of the brain, the object must now be touched only
150with the right hand to achieve the same effect.<br>
151The same effect occurs for visual pairs and reasoning. For example, a
152patient with split brain is shown a picture of a chicken and a snowy
153field in separate visual fields and asked to choose from a list of
154words the best association with the pictures. The patient would choose
155a chicken foot to associate with the chicken and a shovel to associate
156with the snow; however, when asked to reason why the patient chose the
157shovel, the response would relate to the chicken (e.g. "the shovel is
158for cleaning out the chicken coop").<br>
159"Scientists have often wondered whether split-brain patients, who have
160had the two hemispheres of their brain surgically disconnected, are 'of
161two minds'" (Zilmer, 2001). However, recent evidence has emerged that
162despite lack of communication between the two cereberal hemispheres,
163consciousness appears to still take a unified state.<br>
164      <br>
165History<br>
166In the 1950's, research on people with certain brain injuries made it
167possible to suspect that the "language center" in the brain was
168commonly situated in the left hemisphere. One had observed that people
169with lesions in two specific areas on the left hemisphere lost their
170ability to talk, for example. Roger Sperry and his colleague pioneered
171research. In his early work on animal subjects, Sperry made many
172noteworthy discoveries. The results of these studies over the next
173thirty years later led to Roger Sperry being awarded the Nobel Prize in
174Physiology or Medicine in 1981. Sperry received the prize for his
175discoveries concerning the functional specialization of the cerebral
176hemispheres. With the help of so-called "split brain" patients, he
177carried out experiments, and for the first time in history, knowledge
178about the left and right hemispheres was revealed. In the 1960s
179Sperry was later joined by Michael Gazzaniga a psychobiology Ph.D.
180student in his work on split-brain research at Caltech in Pasadena,
181California. Even though Sperry is considered the founder of split-brain
182research, Gazzaniga's clear summaries of their collaborative work are
183consistently cited in psychology texts. In Sperry and Gazzaniga's "The
184Split Brain in Man" experiment published in Scientific American in 1967
185they wanted to explore the extent to which two halves of the human
186brain were able to function independently and whether or not they had
187separate and unique abilities. They wanted to examine how perceptual
188and intellectual skills were affected in someone with a split-brain. At
189Caltech, Gazzaniga worked with Sperry on the effects of split-brain
190surgery on perception, vision and other brain functions. The surgery,
191which was a treatment for severe epilepsy, involved severing the corpus
192callosum, which carries signals between the left-brain hemisphere, the
193seat of speech and analytical capacity, and the right-brain hemisphere,
194which helps recognize visual patterns. At the time this article was
195written, only ten patients had undergone the surgery to sever their
196corpus callosum (corpus callosotomy). Four of these patients had
197consented to participate in Sperry and Gazzaniga's research. After the
198corpus callosum severing all four participants personality,
199intelligence, and emotions appeared to be unaffected. The testing done
200by Sperry and Gazzaniga showed however, the subjects demonstrated
201unusual mental abilities. The researchers created three types of tests
202to analyze the range of cognitive capabilities of the split-brain
203subjects. The first was to test their visual stimulation abilities, the
204second test was a tactile stimulation situation and the third tested
205auditory abilities.<br>
206      <br>
207Visual test<br>
208The first test started with a board that had a horizontal row of
209lights. The subject was told to sit in front of the board and stare at
210a point in the middle of the lights, then the bulbs would flash across
211both the right and left visual fields. When the patients were asked to
212describe afterward what they saw, they said that only the lights on the
213right side of the board had lit up. Next when Sperry and Gazzaniga
214flashed the lights on the right side of the board on the subjects left
215side of their visual field, they claimed to not have seen any lights at
216all. When the experimenters conducted the test again, they asked the
217subjects to point to the lights that lit up. Although subjects had only
218reported seeing the lights flash on the right, they actually pointed to
219all the lights in both visual fields. This showed that both brain
220hemispheres had seen the lights and were equally competent in visual
221perception. The subjects did not say they saw the lights when they
222flashed in the left visual field even though they did see them because
223the center for speech is located in the brain&#8217;s left hemisphere. This
224test supports the idea that in order to say one has seen something, the
225region of the brain associated with speech must be able to communicate
226with areas of the brain that process the visual information.<br>
227      <br>
228Tactile test<br>
229In a second experiment Sperry and Gazzaniga placed a small object in
230the subject's right or left hand, without being able to see (or hear)
231it. Placed in the right hand, the isolated left hemisphere perceived
232the object and could easily describe and name it. However, placed in
233the left hand, the isolated right hemisphere could not name nor
234describe the object. Questioning this result, the researchers found
235that the subjects could later match it from several similar objects;
236tactile sensations limited to the right hemisphere were accurately
237perceived but could not be verbalized. This further demonstrated the
238apparent location (or lateralization) of language functions in the left
239hemisphere.<br>
240      <br>
241Combination of both tests<br>
242In the last test the experimenters combined both the tactile and visual
243test. They presented subjects with a picture of an object to only their
244right hemisphere, and subjects were unable to name it or describe it.
245There were no verbal responses to the picture at all. If the subject
246however was able to reach under the screen with their left hand to
247touch various objects, they were able to pick the one that had been
248shown in the picture. The subjects were also reported to be able to
249pick out objects that were related to the picture presented, if that
250object was not under the screen.<br>
251Sperry and Gazzaniga went on to conduct other tests to shed light on
252the language processing abilities of the right hemisphere as well as
253auditory and emotional reactions as well. The significance of the
254findings of these tests by Sperry and Gazzaniga were extremely telling
255and important to the psychology world. Their findings showed that the
256two halves of the brain have numerous functions and specialized skills.
257They concluded that each hemisphere really has its own functions. One's
258left hemisphere of the brain is thought to be better at writing,
259speaking, mathematical calculation, reading, and is the primary area
260for language. The right hemisphere is seen to possess capabilities for
261problem solving, recognizing faces, symbolic reasoning, art, and
262spatial relationships.<br>
263Further research had continued by Roger Sperry up until his death in
2641994 and Michael Gazzaniga still is researching the split-brain. Their
265findings have been rarely critiqued and disputed, however a popular
266belief that some people are more "right-brained" or "left-brained" has
267developed. In the mid 1980s Jarre Levy, a psychobiologist at the
268University of Chicago, had set out and been in the forefront of
269scientists who wanted to dispel the notion we have two functioning
270brains. She believes that because each hemisphere has separate
271functions that they must integrate their abilities instead of
272separating them. Levy also claims that no human activity uses only one
273side of the brain. In 1998 a French study by Hommet and Billiard was
274published that questioned Sperry and Gazzaniga's study that severing
275the corpus callosum actually divides the hemispheres of the brain. They
276found that children born without a corpus callosum demonstrated that
277information was being transmitted between hemispheres, they concluded
278that subcortical connections must be present in these children with
279this rare brain malformation. They are unclear about whether these
280connections are present in split-brain patients though. Another study
281by Parsons, Gabrieli, Phelps, and Gazzaniga in 1998 demonstrated that
282split-brain patients may commonly perceive the world differently from
283the rest of us. Their study suggested that communication between brain
284hemispheres is necessary for imaging or simulating in your mind the
285movements of others. Scientist Morin's research on inner speech in 2001
286suggested that an alternative for interpretation of commissurotomy
287according to which split-brain patients exhibit two uneven streams of
288self-awareness: a "complete" one in the left hemisphere and a
289"primitive" one in the right hemisphere.<br>
290      <br>
291Hemispheric specialization<br>
292The two hemispheres of the cerebral cortex are linked by the corpus
293callosum, through which they communicate and coordinate actions and
294decisions. Communication and coordination between the two hemispheres
295is essential because each hemisphere has some separate functions.
296The right hemisphere of the cortex excels at nonverbal and spatial
297tasks, whereas the left hemisphere is more dominant in verbal tasks,
298such as speaking and writing. The right hemisphere controls the primary
299sensory functions of the left side of the body. In a cognitive sense
300the right hemisphere is responsible for recognition of objects and
301timing, and in an emotional sense it is responsible for empathy, humor
302and depression. On the other hand, the left hemisphere controls the
303primary sensory functions of the right side of the body and is
304responsible for scientific and math skills, and logic. The extent of
305specialized brain function by an area remains under investigation. It
306is claimed that the difference between the two hemispheres is that the
307left hemisphere is "analytic" or "logical" while the right hemisphere
308is "holistic" or "intuitive". Many simple tasks, especially
309comprehension of inputs, require functions that are specific to both
310the right and left hemispheres and together form a one direction
311systematized way of creating an output through
312the communication and coordination that occurs between hemispheres.<br>
313      <br>
314Role of the corpus callosum<br>
315The corpus callosum is a structure in the brain along the longitudinal
316fissure that facilitates much of the communication between the two
317hemispheres and its main function is in allowing for communication
318between the brain's right and left hemispheres. This structure is
319composed of white matter: millions of axons that have their dendrites
320and terminal buttons projecting in both the right and left hemisphere.
321However, there is evidence that the corpus callosum may also have some
322inhibitory functions. Post-mortem research on human and monkey
323brains show that the corpus callosum is functionally organized. It
324proves that the right hemisphere is superior for detecting faces.
325This organization results in modality-specific regions of the corpus
326callosum that are responsible for the transfer of different types of
327information. Research has revealed that the anterior midbody transfers
328motor information, the posterior midbody transfers somatosensory
329information, the isthmus transfers auditory information and the
330splenium transfers visual information. Although much of the
331interhemispheric transfer occurs at the corpus callosum, there are
332trace amounts of transfer via subcortical pathways.<br>
333Studies of the effects on the visual pathway on split-brained patients
334has revealed that there is a redundancy gain (the ability of target
335detection to benefit from multiple copies of the target) in simple
336reaction time. In a simple response to visual stimuli, split-brained
337patients experience a faster reaction time to bilateral stimuli than
338predicted by model. A model proposed by Iacoboni et al.
339suggests split-brained patients experience asynchronous activity that
340causes a stronger signal, and thus a decreased reaction time. Iacoboni
341also suggests there exists dual attention in split-brained patients,
342which is implying that each cerebral hemisphere has its own attentional
343system. An alternative approach taken by Reuter-Lorenz et al.
344suggests that enhanced redundancy gain in the split brain is primarily
345due to a slowing of responses to unilateral stimuli, rather than a
346speeding of responses to bilateral ones. It is important to note that
347the simple reaction time in split-brained patients, even with enhanced
348redundancy gain, is slower than the reaction time of normal adults.<br>
349      <br>
350Functional plasticity<br>
351Following a stroke or other injury to the brain, functional
352deficiencies are common. The deficits are expected to be in areas
353related to the part of the brain that has been damaged; if a stroke has
354occurred in the motor cortex, deficits may include paralysis, abnormal
355posture, or abnormal movement synergies. Significant recovery
356occurs during the first several weeks after the injury. However,
357recovery is generally thought not to continue past 6 months. If a
358specific region of the brain is injured or destroyed, its functions can
359sometimes be transferred and taken over by a neighboring region. There
360is little functional plasticity observed in partial and complete
361callosotomies; however, much more plasticity can be seen in infant
362patients receiving a hemispherectomy, which suggests that the opposite
363hemisphere can adapt some functions typically performed by its opposite
364pair. In a study done by Anderson, it proved a correlation between the
365severity of the injury, the age of the individual and their cognitive
366performance. It was evident that there was more neuroplasticity in
367older children, even if their injury was extremely severe, than infants
368who suffered moderate brain injury. In some incidents of any
369moderate to severe brain injury, it mostly causes developmental
370impairments and in some of the most severe injuries it can cause a
371profound impact on their development that can lead to long-term
372cognitive effects. In the aging brain, it is extremely uncommon for
373neuroplasticity to occur; "olfactory bulb and hippocampus are two
374regions of the mammalian brain in which mutations preventing adult
375neurogenesis were never beneficial, or simply never occurred"
376(Anderson, 2005).<br>
377      <br>
378Corpus callosotomy<br>
379Corpus callosotomy is a surgical procedure that sections the corpus
380callosum, resulting in either the partial or complete disconnection
381between the two hemispheres. It is typically used as a last resort
382measure in treatment of intractable epilepsy. The modern procedure
383typically involves only the anterior third of the corpus callosum;
384however, if the epileptic seizures continue, the following third is
385lesioned prior to the remaining third if the seizures persist. This
386results in a complete callosotomy in which most of the information
387transfer between hemispheres is lost.<br>
388Due to the functional mapping of the corpus callosum, a partial
389callosotomy has less detrimental effects because it leaves parts of the
390corpus callosum intact. There is little functional plasticity observed
391in partial and complete callosotomies on adults, the most
392neuroplasticity is seen in young children but not in infants.<br>
393It is known that when the corpus callosum is severed that during an
394experimental procedure, the experimenter can ask each side of the brain
395the same question and receive two different answers. When the
396experimenter asks the right visual field/left hemisphere what they see
397the participant will respond verbally, whereas if the experimenter asks
398the left visual field/right hemisphere what they see the participant
399will not be able to respond verbally but will pick up the appropriate
400object with their left hand.<br>
401      <br>
402Memory<br>
403It is known that the right and the left hemisphere have different
404functions when it comes to memory. The right hemisphere is better at
405being able to recognize objects and faces, recall knowledge that the
406individual has already learned, or recall images already seen. The left
407hemisphere is better at mental manipulation, language production, and
408semantic priming but was more susceptible to memory confusion than the
409right hemisphere. The main issue for individuals that have
410undergone a callosotomy is that because the function of memory is split
411into two major systems, the individual is more likely to become
412confused between knowledge they already know and information that they
413have only inferred.<br>
414In tests, memory in either hemisphere of split-brained patients is
415generally lower than normal, though better than in patients with
416amnesia, suggesting that the forebrain commissures are important for
417the formation of some kinds of memory. This suggests that posterior
418callosal sections that include the hippocampal commissures cause a mild
419memory deficit (in standardized free-field testing) involving
420recognition.<br>
421      <br>
422Control<br>
423In general, split-brained patients behave in a coordinated, purposeful
424and consistent manner, despite the independent, parallel, usually
425different and occasionally conflicting processing of the same
426information from the environment by the two disconnected hemispheres.
427When two hemispheres receive competing stimuli at the same time, the
428response mode tends to determine which hemisphere controls behavior.<br>
429Often, split-brained patients are indistinguishable from normal adults.
430This is due to the compensatory phenomena; split-brained patients
431progressively acquire a variety of strategies to get around their
432interhemispheric transfer deficits. One issue that can happen with
433their body control is that one side of the body is doing the opposite
434of the other side called the intermanual effect.<br>
435      <br>
436Attention<br>
437Experiments on covert orienting of spatial attention using the Posner
438paradigm confirm the existence of two different attentional systems in
439the two hemispheres. The right hemisphere was found superior to the
440left hemisphere on modified versions of spatial relations tests and in
441locations testing, whereas the left hemisphere was more object
442based. The components of mental imagery are differentially
443specialized: the right hemisphere was found superior for mental
444rotation, the left hemisphere superior for image generation. It
445was also found that the right hemisphere paid more attention to
446landmarks and scenes whereas the left hemisphere paid more attention to
447exemplars of categories.<br>
448      <br>
449Case studies of split-brain patients<br>
450Patient W.J.<br>
451Patient W.J. was the first patient to undergo a full corpus
452callosotomy in 1962, after undergoing fifteen years of convulsions
453resulting from grand mal seizures. He was a World War II paratrooper
454who was injured at 30 years old during a bombing raid jump over the
455Netherlands, and again in a prison camp following his first injury.
456After returning home, he began to suffer from blackouts in which he
457would not remember what he was doing or where, and how or when he got
458there. At age 37, he suffered his first generalized convulsion. One of
459his worst episodes occurred in 1953, when he suffered a series of
460convulsions lasting for many days. During these convulsions, his left
461side would go numb and he would recover quickly, but after the series
462of convulsions, he never regained complete feeling on his left side.<br>
463Before his surgery, both hemispheres functioned and interacted
464normally, his sensory and motor functions were normal aside from slight
465hypesthesia, and he could correctly identify and understand visual
466stimuli presented to both sides of his visual field. During his surgery
467in 1962, his surgeons determined that no massa intermedia had
468developed, and he had undergone atrophy in the part of the right
469frontal lobe exposed during the procedure. His operation was a great
470success, leading to a decrease in the frequency and intensity of his
471seizures.<br>
472      <br>
473Patient JW<br>
474Patient JW is a right-handed male who was 47 years old at the time
475of testing. He successfully completed high school and has no reported
476learning disabilities. He had his first seizure at the age of 16. At
477the age of 25, he underwent a two-stage resection of the corpus
478callosum for relief of intractable epilepsy. Complete sectioning of the
479corpus callosum has been confirmed by MRI. Post-surgical MRI also
480revealed no evidence of other neurological damage.<br>
481One of the experiments involving JW attempted to determine each
482hemisphere's ability to perform simple addition, subtraction,
483multiplication and division. On each trial, an arithmetic problem was
484presented in the center of the screen followed by a central cross hair.
485After studying the problem, a number posing as the answer was presented
486to each hemisphere exclusively by JW's vision fixated on a central
487cross hair. Probes (stimuli) were then presented for 150 ms to either
488the left visual field/right hemisphere (LVF/RH) or to the right visual
489field/left hemisphere (RVF/LH). The position of the probe fell outside
490any zone of naso-temporal overlap (binocular vision) to ensure that
491stimuli were perceived only by the hemisphere contralateral to the
492visual field of the stimuli. JW was instructed to press a certain key
493if the probe was the correct solution and another key if the probe was
494the incorrect solution. Results showed that the effects of visual field
495was significant with performance of the left hemisphere being better
496than that of the right hemisphere; the left hemisphere correctly chose
497the correct answer on all four arithmetic operations approximately 90%
498of the time while the right hemisphere was at chance. These results
499suggest left hemisphere specialization for calculation.<br>
500J.W. was further tested to determine after-effects on his
501self-recognition and familiar facial recognition. He was tested in
502a study where he would respond yes or no to images presented, by
503pressing a button. These images were ranging from 0&#8211;100% "JW", with the
5040% images being of Dr. Michael Gazzaniga, and the 100% images being of
505J.W. himself. What researchers found supported the idea that there are
506cortical networks in the left hemisphere that play an important role in
507execution of the self-recognition process.<br>
508      <br>
509Patient VP<br>
510Patient VP is a woman who underwent a two-stage callosotomy in 1979
511at the age of 27. Although the callosotomy was reported to be complete,
512follow-up MRI in 1984 revealed spared fibers in the rostrum and
513splenium. The spared rostral fibers constituted approximately 1.8% of
514the total cross-sectional area of the corpus callosum and the spared
515splenial fibers constituted approximately 1% of the area. VP's
516postsurgery intelligence and memory quotients were within normal
517limits.<br>
518One of the experiments involving VP attempted to investigate
519systematically the types of visual information that could be
520transferred via VP's spared splenial fibers. The first experiment was
521designed to assess VP's ability to make between-field perceptual
522judgements about simultaneously presented pairs of stimuli. The stimuli
523were presented in varying positions with respect to the horizontal and
524vertical midline with VP's vision fixated on a central crosshair. The
525judgements were based on differences in color, shape or size. The
526testing procedure was the same for all three types of stimuli; after
527presentation of each pair, VP verbally responded "yes" if the two items
528in the pair were identical and "no" if they were not. The results show
529that there was no perceptual transfer for color, size or shape with
530binomial tests showing that VP's accuracy was not greater than chance.<br>
531A second experiment involving VP attempted to investigate what aspects
532of words transferred between the two hemispheres. The set up was
533similar to the previous experiment, with VP's vision fixated on a
534central cross hair. A word pair was presented with one word on each
535side of the cross-hair for 150 ms. The words presented were in one of
536four categories: words that looked and sounded like rhymes (e.g. tire
537and fire), words that looked as if they should rhyme but did not (e.g.
538cough and dough), words that did not look as if they should rhyme but
539did (e.g. bake and ache), and words that neither looked nor sounded
540like rhymes (e.g. keys and fort). After presentation of each word pair,
541VP responded "yes" if the two words rhymed and "no" if they did not.
542VP's performance was above chance and she was able to distinguish among
543the different conditions. When the word pairs did not sound like
544rhymes, VP was able to say accurately that the words did not rhyme,
545regardless of whether or not they looked as if they should rhyme. When
546the words did rhyme, VP was more likely to say they rhymed,
547particularly if the words also looked as if they should rhyme.<br>
548Although VP showed no evidence for transfer of color, shape or size,
549there was evidence for transfer of word information. This is
550consistent with the speculation that the transfer of word information
551involves fibres in the ventroposterior region of the splenium&#8212;the same
552region in which V.P. had callosal sparing. V.P. is able to integrate
553words presented to both visual fields, creating a concept that is not
554suggested by either word. For example, she combines "head" and "stone"
555to form the integrated concept of a tombstone.<br>
556      <br>
557Kim Peek<br>
558Kim Peek was arguably the most well-known savant. He was born on
559November 11, 1951 with an enlarged head, encephalocele, a malformed
560cerebellum, and an absence of a corpus callosum and both the anterior
561and posterior commissures. He was able to memorize over 9,000 books,
562and information from approximately 15 subject areas. These include:
563world/American history, sports, movies, geography, actors and
564actresses, the Bible, church history, literature, classical music, area
565codes/zip codes of the United States, television stations serving these
566areas, and step by step directions within any major U.S. city. Despite
567these abilities, he had an IQ of 87, was not diagnosed as autistic, and
568was unable to button his shirt, and had difficulties performing
569everyday tasks. The missing structures of his brain have yet to be
570linked to his increased abilities, but they can be linked to his
571ability to read pages of a book in 8&#8211;10 seconds. He was able to split
572his vision so that each eye reads its corresponding page, allowing
573him to read both pages at once. He also had developed language areas in
574both hemispheres, something very uncommon in split-brain patients.
575Language is processed in areas of the temporal lobe, most commonly
576on the left side of the head, and involves a contralateral transfer of
577information before the brain can process what is being read. In Peek's
578case, there was no transfer ability&#8212;this is what led to his development
579of language centers in each hemisphere. Many believe this is the reason
580behind his extremely fast reading capabilities.<br>
581While Peek did not undergo corpus callosotomy, he is considered a
582natural split-brain patient and is critical to understanding the
583importance of the corpus callosum. Kim Peek died in 2009.<br>
584      </td>
585    </tr>
586    <tr>
587      <td style="vertical-align: top;">Wikipedia<br>
588      </td>
589    </tr>
590  </tbody>
591</table>
592
593<br>
594
595<br>
596
597<table style="text-align: left; width: 100%; background-color: rgb(250, 250, 219);" border="1" cellpadding="2" cellspacing="2">
598
599  <tbody>
600    <tr>
601      <td style="vertical-align: top;"> <a href="https://www.nature.com/news/the-split-brain-a-tale-of-two-halves-1.10213">https://www.nature.com/news/the-split-brain-a-tale-of-two-halves-1.10213</a><br>
602      </td>
603    </tr>
604    <tr>
605      <td style="vertical-align: top;"> <big><span style="font-weight: bold;">The split brain: A tale of two halves</span></big><br>
606      <span style="font-style: italic;">14 March 2012</span><br>
607      <span style="font-style: italic;">By David Wolman</span><br>
608      </td>
609    </tr>
610    <tr>
611      <td style="vertical-align: top;">Nature.
61214 March, 2012<br>
613      </td>
614    </tr>
615  </tbody>
616</table>
617
618<br>
619
620<br>
621
622<table style="text-align: left; width: 100%; background-color: rgb(250, 250, 219);" border="1" cellpadding="2" cellspacing="2">
623
624  <tbody>
625    <tr>
626      <td style="vertical-align: top;"> <a href="https://www.psychologytoday.com/blog/the-superhuman-mind/201211/split-brains">https://www.psychologytoday.com/blog/the-superhuman-mind/201211/split-brains</a><br>
627      </td>
628    </tr>
629    <tr>
630      <td style="vertical-align: top;"> <big><span style="font-weight: bold;">Split Brains. Brain's Processing of
631Information Affected by Hemispheric Transfer</span></big><br>
632      <span style="font-style: italic;">November 6, 2012</span><br>
633      <span style="font-style: italic;">By Berit Brogaard, D.M.Sci.,
634Ph.D in The Superhuman Mind</span><br>
635      </td>
636    </tr>
637    <tr>
638      <td style="vertical-align: top;">Psychology Today.
639November 6, 2012<br>
640      </td>
641    </tr>
642  </tbody>
643</table>
644
645<br>
646
647<br>
648
649<table style="text-align: left; width: 100%; background-color: rgb(250, 250, 219);" border="1" cellpadding="2" cellspacing="2">
650
651  <tbody>
652    <tr>
653      <td style="vertical-align: top;"> <a href="https://bernard.pitzer.edu/%7Ehfairchi/pdf/psychology/GazzanigaSplitBrain.pdf">https://bernard.pitzer.edu/~hfairchi/pdf/psychology/GazzanigaSplitBrain.pdf</a><br>
654      </td>
655    </tr>
656    <tr>
657      <td style="vertical-align: top;"> <big><span style="font-weight: bold;">The Split Brain in Man</span></big><br>
658      <span style="font-style: italic;">01/1967</span><br>
659      <span style="font-style: italic;">By Michael S. Gazzaniga</span><br>
660      </td>
661    </tr>
662    <tr>
663      <td style="vertical-align: top;">Scientific American Volume
66401/1967; 217, Issue 2. Pages: 24-29.<br>
665      </td>
666    </tr>
667  </tbody>
668</table>
669
670<br>
671
672<br>
673
674<table style="text-align: left; width: 100%; background-color: rgb(250, 250, 219);" border="1" cellpadding="2" cellspacing="2">
675
676  <tbody>
677    <tr>
678      <td style="vertical-align: top;"> <a href="https://people.psych.ucsb.edu/gazzaniga/michael/PDF/Principles%20of%20Human%20Brain%20Organization%20Derived%20from%20Split-Brain%20Studies.pdf">https://people.psych.ucsb.edu/gazzaniga/michael/PDF/Principles%20of%20Human%20Brain%20Organization%20Derived%20from%20Split-Brain%20Studies.pdf</a><br>
679      </td>
680    </tr>
681    <tr>
682      <td style="vertical-align: top;"> <big><span style="font-weight: bold;">Principles of Human Brain Organization
683Derived from Split-Brain Studies</span></big><br>
684      <span style="font-style: italic;">February, 1995</span><br>
685      <span style="font-style: italic;">By Michael S. Gazzaniga</span><br>
686      </td>
687    </tr>
688    <tr>
689      <td style="vertical-align: top;">Neuron, Vol. 14, 217-228,
690February, 1995.<br>
691      </td>
692    </tr>
693  </tbody>
694</table>
695
696<br>
697
698<br>
699
700<table style="text-align: left; width: 100%; background-color: rgb(250, 250, 219);" border="1" cellpadding="2" cellspacing="2">
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702  <tbody>
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704      <td style="vertical-align: top;"> <br>
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722<table style="text-align: left; width: 100%; background-color: rgb(250, 250, 219);" border="1" cellpadding="2" cellspacing="2">
723
724  <tbody>
725    <tr>
726      <td style="vertical-align: top;"> <a href="https://doktor-lib.com/book/660-novyj-um-korolya/6-yeksperimenty-pri-razdelennyx-bolshix-polushariyax-mozga.html">https://doktor-lib.com/book/660-novyj-um-korolya/6-yeksperimenty-pri-razdelennyx-bolshix-polushariyax-mozga.html</a><br>
727      </td>
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729    <tr>
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731&#1087;&#1086;&#1083;&#1091;&#1096;&#1072;&#1088;&#1080;&#1103;&#1093; &#1084;&#1086;&#1079;&#1075;&#1072;</span></big><span style="font-style: italic;"></span><br>
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