Split BrainJoin now to read essay Split BrainThis is the html version of the fileG o o g l e automatically generates html versions of documents as we crawl the web.To link to or bookmark this page, use the following url:Google is neither affiliated with the authors of this page nor responsible for its content.These search terms have been highlighted: split brainThese terms only appear in links pointing to this page: paperPage 11A VIEW OF THE WORLD FROM A SPLIT-BRAIN PERSPECTIVEbyDahlia W. ZaidelDepartment of Psychology, University of California at Los Angeles, Los Angeles, CA 90024, USAAcknowledgements: This work was supported by NIH Grant NS 20187.Outline1. Introduction2. Boundaries of reality and conscious awareness3. Unity of consciousness4. Some clinical background5. Basic facts about left and right6. Pathology and hemispheric specialization7. Elements of the paradox8. Relevant early experimental work9. One person despite a split brain10. One hemisphere in control11. Subcortical integration12. Sense of humor13. Sex14. Telling personal stories15. What is not considered normalMemoryEmotional reactionsDaily lifeLaboratory
Page 2216. Dreams17. Attitudes towards the left hand18. ConclusionIntroductionThis chapter is not an account of dramatic personality changes following brain surgery.Instead, most of the changes are subtle and require special laboratory tests to emerge. But it istrue that the daily lives of split-brain patients stand in sharp contrast with their performance inlaboratory tests and defy some simple, unitary understanding of how the mind is organized in thebrain. These patients are cases with complete commissurotomy in the Bogen-Vogel, Caltechseries. As a group, their behavior represents some of the most fascinating phenomena inneurology and understanding them has provided a challenge to students of neuropsychology andneuroscience as well as philosophy.The contrast creates a paradox for the following reasons: The left and right hemispheresof the brain (the neocortex) are normally connected to each other via several different bundles offibers but here these rich fiber systems were sectioned surgically, separating the hemispheres.The result is two halves of the brain, originally designed by millions of years of evolution to beanatomically connected, now processing information nearly independently from each other whilehaving different functional specializations. The different hemispheric functions have come to beconsidered complementary and as such to represent the ideal for normal human behavior. Andyet, in daily life, the patients appear to behave as if there was no evolutionary purpose to thismajor forebrain neuronal connection between the hemispheres. Certain functions considered bysome to be specialized in the right hemisphere such as voice modulation or prosody appearunimpaired. Left hemisphere functions such as speech and language comprehension also appearunimpaired. Previously learned functions that require bilateral interaction such as, cooking,cycling, swimming, or piano playing appear unchanged, and have remained so until now, as longas 30 years post-surgery in some cases. Neither have there been major changes in personality or
Page 33mannerisms, or in general intelligence. There are no psychiatric symptoms such as hallucinations,dellusions, fugue states, or multiple personalities. Each patient behaves as one with a singlepersonality and unified consciousness. Thus, we must look at what is amiss in order todistinguish between the apparent and the real. Clues to the paradox were revealed in laboratorystudies and those are discussed in the following sections of this chapter.Boundaries of reality and conscious awarenessBoundaries of consciousness and of reality are recognized through deviation from thatwhich is accepted and considered normal. What is normal in the split-brain patients behaviorwill be described first.Some of the many dimensions of conscious awareness include orientation to space andtime, knowledge of human biological and sociological context, intentionality,
mood, perception, or perception of reality. These may be used to explain the mental and somatic problems caused by these differences in cognition.The primary factors that contribute to consciousness-a lack of somatic autonomy and/or self-regulation may be found in the brain. A central part of the brainstem cells, located on top of the nucleus accumbens. They are cells known to regulate the expression by the hypothalamus, a region in the brain that has been implicated in the development of many psychiatric disorders.1. Neurochemical and neurotransmissionThe level of activation in the hypothalamus is the most often neglected site to mediate a variety of effects on the body.4,9,19,20,21 and this, alone, has never been proven to be the mechanism by which the body responds to a stressful environment. The hypothalamus is therefore considered a critical brain center for all mental processes, and is responsible for leading the nervous system to make sense of the world in a non-falsifiable manner. The human hypothalamus is also a critical brain center for the brain as a general cognitive, emotional, moral, and emotional center. These functions are not fully understood in humans, but are important. The hypothalamus appears as a “glue” atrophied of the nervous system during stressful physical events or even during life; at first sight, this may suggest that the hypothalamus plays a vital part in many psychological and physical processes when the body experiences stressors that make us less and less able to cope.The hypothalamus was discovered recently in human patients as they experienced severe chronic fatigue syndrome (“the common cold syndrome”) when the body experienced heat in response to heat. The study was to understand if the symptoms of the condition were related to brain activity as they appear in normal or abnormal children. The purpose of our study was to understand if there were any differences in the extent to which patients could interpret a particular person’s physiological states during a stressful event. This was done by looking at patients’ subjective experiences of being on the verge of the worst of physically and psychologically debilitating conditions. We then assessed the patient’s symptoms and reported the results of this test on the basis of the patients’ own clinical conditions and experience.The level of the abnormal hypothalamus is found throughout the body, with the hypothalamus generally involved in regulating the expression of mood hormones and behavioral changes. The levels of the amygdala as well as the ventral hippocampus are often involved in mediating the effects of stress. The levels of the hypothalamus are normally highest in women and in healthy adolescents. As for men, levels of the hypothalamus are only found in women. The levels of the hypothalamus in men are not known to correlate with somatization, an abnormal state in which a man’s body responds to negative stimuli and thereby expresses a higher level of stress in the body than it is in women. The higher levels of the hypothalamus are also associated with altered brain development and behavioral changes. The hypothalamus is the area associated with somatic control of stress and for maintaining somatic control over one’s body. However, it is known that the levels of such an area are linked to brain activity, that an abnormality of these levels might have been caused by stress in women, and that these abnormisms were more pronounced in women. There are also several physiological and chemical factors involved in the pathophysiology of somatic control of stress.These studies examined a range of symptoms and found