8/9/2019 Rumors and Wrong Facts About Brain

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Rumors and wrong facts about brain

* Humans use only 10% or less of their brain. There is no scientific basis for this assertion.Many functional brain imaging studies show activated regions encompassing well over 10% ofthe brain. Perhaps the most remarkable thing about this myth is that nobody has ever been ableto pin down its origin. Some possibilities have been discussed by Benjamin Radford,[2] EricChudler,[3] and The Two Percent Company.[4]

o This misconception most likely arose from a misunderstanding (or misrepresentation inan advertisement) of neurological research in the late 1800s or early 1900s when researcherseither discovered that only about 10% of the neurons in the brain are firing at any given time orannounced that they had only mapped the functions of 10% of the brain up to that time(accounts differ on this point).[citation needed]

o Another possible origin of the misconception is that only 10% of the cells in the brainare neurons; the rest are glial cells that, despite being involved in learning, do not function in thesame way that neurons do.

o Einstein is reported as quipping that people typically only use 10% of their brains. The

popular press took this as fact, although the comment was meant only facetiously.[5]o Lower level of brain activation does not mean a lower performance of cognitive

functions; this variable has confounded scientists, because some 'gifted' individuals showedless activity than the average person. Haier proposed that indeed more gifted individuals mightpossess more efficient brain circuits.[citation needed]

o Some New Age proponents propagate this belief by asserting that the "unused" ninetypercent of the human brain is capable of exhibiting psychic powers and can be trained toperform psychokinesis and extra-sensory perception. However, there is still no proof of this, andneurologists say that this is not possible.[citation needed]

* Learning can be achieved more powerfully through subliminal techniques. The extent towhich subliminal techniques can influence learning depends largely on what level of perceptionthe techniques affect.[]

o Learning in the sense of implicit memory formation has been demonstrated even inpatients who are under general anesthetic. Words played to patients during operations werelater found to influence implicit recall tasks.About structure

* The human brain is firm and grey. The living brain is soft[7] and pale grey in color. Itbecomes firm and darker grey when it is preserved with resins.

* Mental abilities are absolutely separated into the left and right cerebral hemispheres.[8]

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Some mental functions such as speech and language (cf. Broca's area, Wernicke's area) tendto be localized to specific areas in one hemisphere. If one hemisphere is damaged at a veryearly age, however, these functions can often be recovered in part or even in full by the otherhemisphere.[] Other abilities such as motor control, memory, and general reasoning are spreadequally across the two hemispheres.[9] See lateralization of brain function.

* New neurons cannot be created. Although neurons cannot undergo mitosis, neurogenesis,

the creation of new neurons continues postnatally. Adult neurogenesis has been observed inavian,[10] primates,[11][12] and humans. In humans, the results have been observed in thesubventricular and subgranular zones.[13] Both of these zones are allocortical, possessingfewer than six layers. Some studies have suggested that postnatal neurogenesis also occurs inthe neocortex,[14][15][16] an idea that is disputed.[17] Neurological changes, including from thelearning of new functions and capabilities, can occur without neurogenesis through continueddevelopment of white matter, the neurological tissue that facilitates connections betweenneurons