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66 67 68</head> 69<body> 70 71<noscript> 72<iframe src="https://www.googletagmanager.com/ns.html?id=GTM-5S4DVK8" 73height="0" width="0" style="display:none;visibility:hidden"></iframe> 74 75<div><img src="https://mc.yandex.ru/watch/57239965" style="position:absolute; left:-9999px;" alt="" /></div> 76</noscript> 77 78 79 80 81 82<a href="https://neuroclusterbrain.com/">back to main page</a><br> 83 84<br> 85 86<big><b>Scientific articles about “split-brain” experiments</b></big><br> 87 88<br> 89 90<br> 91 92For some <a href="split_brain_experiments_videos.html">movies about 93“split-brain” experiments please click here</a>.<br> 94 95<br> 96 97<table style="text-align: left; width: 100%; background-color: rgb(250, 250, 219);" border="1" cellpadding="2" cellspacing="2"> 98 99 <tbody> 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’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 0–100% "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—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 8–10 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—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"> 701 702 <tbody> 703 <tr> 704 <td style="vertical-align: top;"> <br> 705 </td> 706 </tr> 707 <tr> 708 <td style="vertical-align: top;"> <br> 709 </td> 710 </tr> 711 <tr> 712 <td style="vertical-align: top;"> <br> 713 </td> 714 </tr> 715 </tbody> 716</table> 717 718<br> 719 720<br> 721 722<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> 728 </tr> 729 <tr> 730 <td style="vertical-align: top;"> <big><span style="font-weight: bold;">Эксперименты при разделенных больших 731полушариях мозга</span></big><span style="font-style: italic;"></span><br> 732 </td> 733 </tr> 734 <tr> 735 <td style="vertical-align: top;">Пенроуз Р. Новый ум короля. <br> 736 </td> 737 </tr> 738 </tbody> 739</table> 740 741<br> 742 743<br> 744 745<br> 746 747<br> 748 749<iframe src="content_disclaimer.html" style="border: medium none ; background-color: transparent;" align="middle" height="100%" scrolling="no" width="100%"></iframe> 750</body></html>
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