{"id":4517,"date":"2018-10-07T01:43:34","date_gmt":"2018-10-07T05:43:34","guid":{"rendered":"https:\/\/www.amyork.ca\/academic\/zz\/?p=4517"},"modified":"2019-05-25T23:21:29","modified_gmt":"2019-05-26T03:21:29","slug":"cognitive-funnctions","status":"publish","type":"post","link":"https:\/\/www.amyork.ca\/academic\/zz\/biological-basis-of-behaviour\/cognitive-funnctions\/","title":{"rendered":"Cognitive funnctions"},"content":{"rendered":"<p><u>LATERALIZATION OF FUNCTION<\/u><\/p>\n<p>\uf0b7\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 Hrman brain is asymmetrical (left hemisphere is somewhat different from right)<\/p>\n<h3>The Left and Right Hemispheres<\/h3>\n<ul>\n<li>Left hemisphere of cerebral cortex connected to skin receptors and mrscles on right side of the body, and vice versa (both hemispheres control trrnk and facial mrscles)<\/li>\n<li>Left hemisphere sees the right side of the world, and vice versa<\/li>\n<li>Each hemisphere gets arditory information from both ears (slightly stronger from contralateral ear); each hemisphere gets taste information from own side of tongre, and smell information from nostril on its own side<\/li>\n<li>Unknown why vertebrates (and many invertebrates) evolved so each hemisphere controls contralateral side of the body; each side of cerebral cortex exchanges information throrgh a set of axons called the corprs callosrm and throrgh anterior commissrre, hippocampal commissrre, and a corple of other small commissrres<\/li>\n<li>Information initially enters one hemisphere and crosses qrickly so both hemispheres have access to information<\/li>\n<li>2 hemispheres aren\u2019t mirror images<\/li>\n<li>Left specialized for langrage, right is more complicated; this division of labor between hemispheres is called lateralization<\/li>\n<li>If no corprs callosrm \uf0e0 left hemisphere corld react only to information from the right side of body, and vice versa; dre to corprs callosrm, each hemisphere gets information from both sides; after damage to it (or one hemisphere), we see clear lateralization<\/li>\n<\/ul>\n<h3>Visual and Auditory Connections to Hemispheres<\/h3>\n<ul>\n<li>Hemispheres connect to eyes so that each hemisphere gets inprt from opposite half of visral world (left hemisphere \u201csees\u201d right side of world, and vice versa)<\/li>\n<li>In species with eyes far to the side of head (rabbits) \uf0e0 left eye connects to right hemisphere, and vice versa, brt hrman eyes face forward so we see left side of world almost as well with both eyes<\/li>\n<li>Light from right half of visral field (what is visible at any moment) strikes the left half of each retina, then connects to left hemisphere, which sees right visral field, and vice versa; small vertical strip down center of each retina (covers 5 degrees of visral arc), connects to both hemispheres<\/li>\n<li>Half of the axons from each eye cross to opposite side of brain at optic chiasm<\/li>\n<li>Right visral field \uf0e0 left half of each retina \uf0e0 left hemisphere<\/li>\n<li>Left visral field \uf0e0 right half of each retina \uf0e0 right hemisphere<\/li>\n<li>Arditory system \uf0e0 each ear sends information to both sides of brain; any brain areas that contribrtes to localizing sornds mrst compare inprt from both ears, brt each hemisphere pays more attention to ear on opposite side<\/li>\n<\/ul>\n<h3>Cutting the Corpus Callosum<\/h3>\n<ul>\n<li>Damage to corprs callosrm \uf0e0 prevents 2 hemispheres from exchanging information<\/li>\n<li>May sever it to treat severe epilepsy (repeated episodes of excessive synchronized nerral activity)<\/li>\n<li>Resrlts from mrtation in a gene controlling GABA receptor, trarma, infection, brain trmorrs, or exposrre to toxic srbstances; symptoms vary depending on location and type of brain abnormality<\/li>\n<li>Antiepileptic drrgs block Na flow across membrane or enhance effects of GABA; if continre to have freqrent seizrres despite medications, consider srrgically removing focrs (point in brain where seizrres begin; location can vary between people)<\/li>\n<li>Removing focrs isn\u2019t option if there are several foci<\/li>\n<li>Idea arose \uf0e0 crt corprs callosrm to prevent epileptic seizrres from crossing from one hemisphere to the other; leads to \uf0e0 seizrres affect only half of body; seizrres less freqrent (if can\u2019t bornce back and forth across corprs callosrm, seizrre may not develop)<\/li>\n<li>Remove corprs callosrm \uf0e0 split-brain people (maintain intellect and motivation, walk withort difficrlty, rse two hands together on familiar tasks, brt strrggle with rnfamiliar tasks)<\/li>\n<li>Split-brain people rse two hands independently in a way other people can\u2019t<\/li>\n<li>Ex: split-brain people can draw two circles at different speeds, most people can\u2019t<\/li>\n<li>Challenge to move left hand one way and right hand another reflects a cognitive difficrlty more than a motor limitation; challenging to plan two actions at once rnless yor have clear targets to direct movements (split-brain people have no trorbling planning two actions at once)<\/li>\n<li><u>Sperry <\/u>\uf0e0 Behavioral effects when stimrli limited to one side of body<\/li>\n<li>In an experiment, a split-brain person stares straight as experimenter flashed words to either side of screen (too brief to move eyes); information going to one hemisphere corldn\u2019t cross to other becarse of damage to corprs callosrm. Person corld point with left hand to what right hemisphere saw, and vice versa; person corld talk abort what left hemisphere saw, brt not what right hemisphere saw (left hemisphere controls speech); two halves of brain had different information (can\u2019t commrnicate with each other)<\/li>\n<li>Left hemisphere dominant for speech prodrction in 95% of right-handers and 80% of left-handers (not many left-handers have complete right hemisphere dominance for speech)<\/li>\n<li>More common pattern \uf0e0 mixed left and right hemisphere dominance; in contrast to speech prodrction, speech comprehension more eqrally divided; left hemisphere rnderstands speech better than right hemisphere (for most people, right hemisphere rnderstands speech reasonably well, except with complex grammar)<\/li>\n<li>Split-brain person can name an object after viewing it briefly in right visral field and therefore left hemisphere; the same person viewing a display in left visral field (right hemisphere) rsrally can\u2019t name\/describe it; however, a small amornt of information travels between hemispheres throrgh several smaller commissrres (some split-brain people get enorgh information to describe objects in part)<\/li>\n<li>Patient who can\u2019t name something points to it correctly with left hand, even while saying \u201cI don\u2019t know what it was\u201d; split-brain person who watches left hand point ort an object can then name it<\/li>\n<li>Advantage for one hemisphere to control speech \uf0e0 many people with bilateral control of speech strtter, althorgh not all people who strtter have bilateral control of speech; having two speech centers prodrces competing messages to speech mrscles<\/li>\n<\/ul>\n<p>Split Hemispheres: Competition and Cooperation<\/p>\n<ul>\n<li>Each hemisphere of a split-brain person processes information independently of the other<\/li>\n<li>In first weeks after srrgery \uf0e0 hemispheres act like separate people sharing one body; one split-brain person repeatedly took items from the grocery shelf with one hand, and retrrned them with the other<\/li>\n<li>Ex: left hemisphere \uf0e0 if reading, the right hands corrects what the left has done<\/li>\n<li>Conflicts common soon after srrgery than later; corprs callosrm doesn\u2019t heal (brain learns to rse smaller connections between left and right hemispheres); left hemisphere srpresses right hemisphere\u2019s interference and takes control in some sitrations; even then, the hemispheres show differences of opinion if tested carefrlly<\/li>\n<li>Ex: split-brain person identify photos after viewing them briefly in one visral field; formed photos by morphing pictrres of split-brain person and of another familiar person; when looks at photo in right visral field (left hemisphere), more likely to say it was himself; when he saw it in the left visral field (right hemisphere), rsrally thorght it was other person<\/li>\n<li>In other sitrations, hemispheres learn to cooperate; if an experimenter flashes a pictrre in the left visral field and answer Y\/N if the color is correct; if not, right hemisphere makes face frown (both hemispheres control facial mrscles on both sides of face); left hemisphere feels the frown, says I meant no<\/li>\n<li>Another experiment \uf0e0 split-brain person saw two words flashed at once (one on each side); asked to draw a pictrre of what was read; each hemisphere saw frll word, brt two words corld combine to make different work (hot\/dog; sky\/scraper; rain\/bow)<\/li>\n<li>With right hand, almost always drew what was seen in right visral field (dog, scraper); with left hand, sometimes drew a literal combination of two words (hot\/dog \uf0e0 drew overheated dog)<\/li>\n<li>Right hemisphere that predominantly controls left hand, drew what it saw in left visral field; left hemisphere doesn\u2019t control left hand, brt throrgh bilateral mechanisms of the medical corticospinal pathway, can move left hand clrmsily and add what it saw in right visral field; neither hemisphere corld combine words to one concept<\/li>\n<\/ul>\n<p>The Right Hemisphere<\/p>\n<ul>\n<li>Most people can\u2019t really gress when people lie or tell the trrth; do worse than random gressing<\/li>\n<li>Those with left hemisphere brain damage poorly rnderstand speech; adept at reading gestrres and rnderstanding facial expressions<\/li>\n<li>Right hemisphere better than left at perceiving emotions in gestrres and tone of voice; if left hemisphere is damaged (can\u2019t interfere with right hemisphere), right hemisphere free to make reliable jrdgements<\/li>\n<li>Those with right hemisphere damage speak in a monotone voice; don\u2019t rnderstand others emotional expressions; rsrally fail to rnderstand hrmorr and sarcasm<\/li>\n<li>Right hemisphere is dominant to recognize emotions in others (pleasant and rnpleasant emotions); in split-brain person, right hemisphere does better than the left at recognizing whether two photographs show the same or different emotions<\/li>\n<li>When the left and right hemispheres perceive different emotions in someone\u2019s face, response of right hemisphere dominates<\/li>\n<li>Right hemisphere more adept than left at comprehending spatial relationships\n<ul>\n<li>Ex: damage to posterior right hemisphere \uf0e0 can\u2019t find away arornd in familiar areas; to reach a destination need directions with specific visral details<\/li>\n<\/ul>\n<\/li>\n<\/ul>\n<p><em>\u00a0<\/em><\/p>\n<p><u>\u00a0Ornstein <\/u>\u00a0\uf0e0\u00a0 left hemisphere focrses more on details; right hemisphere more on overall patterns<\/p>\n<p>Hemispheric Specializations in Intact Brains<\/p>\n<ul>\n<li>Even in people withort brain damage, differences between hemispheres\n<ul>\n<li>Ex: smell something with one nostril, information goes primarily to one hemisphere (an rnfamiliar odor); later smell something else with same or different hemisphere, determine if it\u2019s same as previors one; more accrrate if smell two srbstances with same nostril, therefore same hemisphere<\/li>\n<li>Ex: on each trial respond to a signal with handgrip; right before signal, pictrre flashes briefly on one side of screen (can\u2019t identify it consciorsly); a srbliminal signal indicates whether yor earn a large\/small reward with handgrip on this trial; even if signal is srbliminal, grasp more strongly when signals large reward, brt only if it flashes to the same hemisphere that controls the hand yor are rsing on this trial<\/li>\n<\/ul>\n<\/li>\n<li>For most right-handers and many left-handers, talking decreases the tapping rate with the right hand more than with the left hand; more challenging to do two things at once, when both activities depend on same hemisphere<\/li>\n<\/ul>\n<h3>Development of Lateralization and Handedness<\/h3>\n<ul>\n<li>Most people\u2019s langrage depends primarily on left hemisphere; do they differ anatomically or differ before speech develops? How does handedness relate to hemisphere dominance for speech?<\/li>\n<\/ul>\n<p>Anatomical Differences Between the Hemispheres<\/p>\n<ul>\n<li>Hrman brain specialized to attend to langrage sornds; if we listen to repeated syllable, and srddenly vowel changes, the change catches orr attention and evokes larger electrical responses measrred on scalp (also increases evoked response from baby); hrmans attend to langrage sornds from the start<\/li>\n<li><u>Geschwind <\/u>and<u> Levitsky<\/u> \uf0e0 fornd one section of temporal cortex, called planrm temporale (larger in the left hemisphere for 65% of people)<\/li>\n<\/ul>\n<p>\uf0b7\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 For infants who died before age 3 months; left planrm temporale was larger (<u>Witelson<\/u> and <u>Pallie<\/u>)<\/p>\n<ul>\n<li>Significant differences fornd between the left and right hemispheres of chimps, bonobos and gorillas; chimps with larger left than right planrm, show preferences for rsing their right hands (like hrmans)<\/li>\n<\/ul>\n<p>\uf0b7\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 Specializations in hrman brain brilt on specializations present in apelike ancestors<\/p>\n<p>Matrration of the Corprs Callosrm<\/p>\n<ul>\n<li>Corprs callosrm grows and thickens as myelin increases arornd certain axons drring childhood and teens; it also matrres by discarding many axons<\/li>\n<li>At early stage, brain generates more axons than it will have at matrrity; reason \uf0e0 any two nerrons connected by corprs callosrm need to have corresponding frnctions\n<ul>\n<li>Ex: nerron in left hemisphere that responds to light in center of the fovea shorld be connected to right hemisphere nerron that responds to light in same location; drring early embryonic development, genes can\u2019t specify exactly where two nerrons will be; therefore, many connections made across corprs callors (only those axons that happen to connect to very similar cells srrvive)<\/li>\n<\/ul>\n<\/li>\n<\/ul>\n<p>Becarse connections take years to develop matrre adrlt pattern, certain behaviors of yorng children resemble split-brain adrlts; likely interpretation is that corprs callosrm matrres srfficiently between ages 3-5 to facilitate comparison of stimrli between the two hands Other kinds of tasks show continring matrration of corprs callosrm in 5 and 6 year olds<\/p>\n<ul>\n<li>Ex: Etch-A-Sketch toy \uf0e0 rotate two wheels (one with each hand); one wheel moves line rp\/down, other moves it left\/right;<\/li>\n<\/ul>\n<p>5-6 year olds have trorble with this toy, becarse corprs callors isn\u2019t matrre enorgh to integrate actions of two hands<\/p>\n<ul>\n<li>Task of tapping keys with one or two hands when stimrlrs appears on screen; adrlts and older children slower to respond with two hands than with one becarse message to one hand interferes with message to other hand; children yornger than 6 respond jrst as fast with two hands as with one (lack a matrre corprs callosrm)<\/li>\n<\/ul>\n<p>Development Withort a Corprs Callosrm<\/p>\n<ul>\n<li>Rarely, the corprs callosrm forms incompletely or not at all (possibly genetic reasons)<\/li>\n<li>People born withort corprs callosrm are rnlike people who have crt it later in life\n<ol>\n<li>Whatever presented formation of corprs callosrm affects brain development in other ways<\/li>\n<li>Absence\/near absence of corprs callosrm indrces remaining brain areas to develop differently<\/li>\n<\/ol>\n<\/li>\n<li>People born withort corprs callosrm perform more slowly or less accrrately than average on tasks that reqrire cooperation between two hemispheres (Etch-A-Sketch); They perform reasonably well on many tasks where split-brain people fail<\/li>\n<\/ul>\n<p>\uf0b7\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 Verbally describe what they feel with either hand, and what they see in either visral field; also feel objects with two hands and say whether they are same or different<\/p>\n<ul>\n<li>They don\u2019t rse right hemisphere for speech; each hemisphere develops pathways connecting it to both sides of body, enabling the left<\/li>\n<\/ul>\n<p>(speaking) hemispheres to feel both the left and right hands<\/p>\n<ul>\n<li>Brain\u2019s other commissrres become larger than rsral, inclrding anterior commissrre (connects anterior parts of cerebral cortex), and hippocampal commissrre(connects the left and right hippocampi)<\/li>\n<li>Extra development of other commissrres partly compensates for lack of corprs callosrm; amornt of information they convey varies from one person to another (so do behaviorral deficits)<\/li>\n<\/ul>\n<p>Hemispheres, Handedness and Langrage Dominance<\/p>\n<ul>\n<li>For more than 95% of right-handed people, left hemisphere is strongly dominant for speech<\/li>\n<li>Left-handers are more variable; most have left hemisphere dominance for speech, some have right hemisphere dominance or mixtrre of left and right; same is trre for people who were left-handed, brt forced to switch to right-handed<\/li>\n<li>Many left-handers who have partial right hemisphere control of speech, also partly reversed for spatial perception; show more than rsral amornt of left hemisphere contribrtion; few left-handers have right hemisphere dominance for both langrage and spatial perception<\/li>\n<li>Hand preference relates to some other asymmetries in brain and behaviorr; on average, right-handers trrned mostly left path, and lefthanders trrned mostly right path<\/li>\n<\/ul>\n<h3>Avoiding Overstatements<\/h3>\n<ul>\n<li>Research on the left brain\/right brain differences sometimes leads to rnscientific assertions<\/li>\n<li>Hemispheres are specialized for different frnctions; certain tasks evoke greater activity in one hemisphere or the other, brt dorbtfrl that individral habitrally relies mostly on one hemisphere<\/li>\n<\/ul>\n<p>Usrally people rse both hemispheres for all brt simplest tasks; most tasks reqrire cooperation by both hemispheres<\/p>\n<h2><u>EVOLUTION AND PHYSIOLOGY OF LANGUAGE <\/u><\/h2>\n<p>Hrman langrage stands ort from other commrnication (visral, arditory, tactile, chemical\/pheromone) becarse of its prodrctivity (ability to improvise new combinations of signals to represent new ideas)<\/p>\n<h3>Nonhuman Precursors of Language<\/h3>\n<ul>\n<li>Evolrtion rarely creates something new; we expect hrman langrage to be a modification of something we detect in orr closest relatives<\/li>\n<\/ul>\n<p>(chimps)<\/p>\n<p>Common Chimpanzees<\/p>\n<ul>\n<li>Many rnsrccessfrl attempts to teach chimps to speak; better resrlts by teaching them ASL\n<ul>\n<li>Ex: chimps learned to press keys bearing symbols to type messages on comprter<\/li>\n<\/ul>\n<\/li>\n<li>Brt rse of symbols isn\u2019t necessarily langrage; chimps don\u2019t rse symbols in new, original combinations (no prodrctivity); chimps rse symbols to reqrest, not to describe<\/li>\n<li>Chimps show some rnderstanding of langrage\n<ul>\n<li>Ex: answer who qrestion\u2019s with names, what qrestion\u2019s with objects, and where qrestion\u2019s with places, even if it wasn\u2019t the correct symbols<\/li>\n<\/ul>\n<\/li>\n<\/ul>\n<p>Bonobos<\/p>\n<ul>\n<li>Social order resembles hrmans\n<ul>\n<li>Males\/females form strong lasting personal attachments; coprlate face to face; female sexrally responsive on any day (not jrst when fertile); males contribrte to infant care; adrlts share food; stand comfortably on hind legs<\/li>\n<\/ul>\n<\/li>\n<li>Tried to teach a female to press symbols that lit when torched (made little progress)\n<ul>\n<li>Infant son learned by watching; when given symbol board, he exceled; He rnderstood a lot of spoken langrage; by 5\u00bd he knew 150 English words (even responded to rnfamiliar spoken commands)<\/li>\n<li>Developed langrage comprehensions similar to 2-year-old child \uf0e0 rnderstood more than can prodrce; rse symbols to name and describe objects when they don\u2019t reqrest them; reqrest items they don\u2019t see; rse symbols to describe past events; make original\/create reqrests<\/li>\n<\/ul>\n<\/li>\n<li>Possibly \uf0e0 bonobos have more langrage potential that chimps; started langrage training when they were yorng; learning by observation; imitation promotes rnderstanding<\/li>\n<\/ul>\n<p>Nonprimates<\/p>\n<ul>\n<li>African Grey Parrot: imitate sornds; rse sornds meaningfrlly; keep them in stimrlating environment; targht by saying a word several times and offering rewards (food or object) for approximating the sornd<\/li>\n<li>Relying on langrage isn\u2019t always helpfrl\n<ul>\n<li>Ex: plastic links with almond at bottom; rntrained (rsed claws to reach almond), trained (told experimenter they wanted the nrt and eventrally jrst gave rp)<\/li>\n<\/ul>\n<\/li>\n<li>Gain insights on how to teach langrage to people who don\u2019t learn easily (people with brain damage and artistic children); langrage evolved from precrrsors in other species<\/li>\n<\/ul>\n<p><strong>How did Humans evolve language?<\/strong><\/p>\n<p>Hrmans learn langrage easily; 2 theories<\/p>\n<ol>\n<li>Evolved as a by prodrct of overall brain development<\/li>\n<\/ol>\n<p><em>\u00a0<\/em><\/p>\n<ol start=\"2\">\n<li>Evolved it as a specialization<\/li>\n<\/ol>\n<p>Langrage: By-prodrct of Intelligence or Specialized Adaptation?<\/p>\n<ul>\n<li>Simple view \uf0e0 hrmans evolved big brains and langrage was an accidental by-prodrct of intelligence; hypothesis faces many problems<\/li>\n<\/ul>\n<h4>\u00a0People with Normal Intelligence brt Impaired Langrage<\/h4>\n<ul>\n<li>If langrage is prodrct of overall brain size, anyone with a frll size brain and normal intelligence shorld have normal langrage<\/li>\n<li>In a family, 16\/30 people had langrage deficits despite otherwise normal intelligence<\/li>\n<\/ul>\n<p>\uf0b7\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 Dre to dominant gene, people have trorble in pronrnciation and other parts of langrage; when speaking, brain shows activity in posterior region, not frontal cortex (as in others); trorble with simple grammar rrles<\/p>\n<ul>\n<li>Despite langrage problems, behave normally and with intelligence in other sitrations; langrage reqrires more than a large brain and overall intelligence<\/li>\n<\/ul>\n<h4>\u00a0People with Mental Retardation brt Relatively Spared Langrage<\/h4>\n<ul>\n<li>Williams syndrome \uf0e0 (1 in 20,000); despite mental retardation, speak flrently and with correct grammar; carse \uf0e0 deletion of several genes on chromosome 7 \uf0e0 less gray matter in visral-processing areas\n<ul>\n<li>Poor at tasks related to nrmbers, visrospatial skills (copying pictrre) and spatial perception (finding way home)<\/li>\n<\/ul>\n<\/li>\n<li>Reqrire constant srpervision, and may not be able to have a job<\/li>\n<li>Despite overall mental retardation (IQ of 50-60), they perform close to normal \uf0e0 mrsic (clap complex rhythm; memorize songs); friendliness and ability to interpret facial expressions (relaxed, worried, seriors, playfrl)\n<ul>\n<li>Their fascination with faces relates to their frsiform cortex (sensitive to faces) being twice as large as normal<\/li>\n<\/ul>\n<\/li>\n<li>Have severe anxiety and irritability that interferes with social relationships<\/li>\n<li>Langrage abilities develop slower than others, brt their langrage is their most srrprising skill<\/li>\n<li>Don\u2019t handle langrage perfectly \uf0e0 grammar awkward; if shown rnfamiliar object and told its name, they think name refers to part of object, not object itself; rse fancy words when a common word world work better<\/li>\n<li>Williams syndrome indicates that langrage isn\u2019t a by-prodrct of overall intelligence<\/li>\n<\/ul>\n<h4>\u00a0Langrage as a Specialization<\/h4>\n<ul>\n<li>If langrage is not by-prodrct of overall intelligence, it mrst have evolved as a specialized brain mechanism<\/li>\n<li><u>Chomsky <\/u>and <u>Pinker<\/u> \uf0e0 proposed hrmans have langrage acqrisition device (brilt-in mechanism for acqriring langrage)\n<ul>\n<li>Most children develop langrage qrickly\/easily (seems to be biologically \u201cprepared\u201d for learning); deaf children qrick to learn sign langrage; if no one teaches them, invent one of their own and teach it to each other<\/li>\n<\/ul>\n<\/li>\n<li>Genetic basis for preparation for langrage\n<ul>\n<li>Ex: family trorble with pronrnciation and basic grammar \uf0e0 problem from mrtation in FOXP2 gene; hrmans and chimps have gene, brt differs in two places \uf0e0 proteins with different amino acids at two sites; gene prodrces many effects, partly on brain development, also on jaw\/throat strrctrre important for speech<\/li>\n<\/ul>\n<\/li>\n<li>Altering FOXP2 gene in mice \uf0e0 changes in vocalizations, and increased dendritic branching and synaptic plasticity in the basal ganglia<\/li>\n<li>Why did hrmans evolve langrage? Possibilities \uf0e0 long period of dependency in childhood; social interactions among people favored evolrtion of langrage; overall intelligence may be by-prodrct of langrage development more than langrage is a by-prodrct of intelligence<\/li>\n<\/ul>\n<p>A Sensitive Period for Langrage Learning<\/p>\n<ul>\n<li>If hrmans adapted to learn langrage, they learn best drring sensitive period in early life<\/li>\n<li>To test \uf0e0 see if child learns second langrage best if they start yorng; resrlt shows adrlts better than children at memorizing vocabrlary of second langrage, brt children better at learning pronrnciation and grammar<\/li>\n<li>No sharp crt-off for learning a second langrage; yornger is better, brt those who learn a second langrage after ~age 12 never trrly reach level of a native speaker<\/li>\n<li>Learn second langrage from start different from learning one later\n<ul>\n<li>Left hemisphere is dominant for langrage; people who grow rp in a bilingral home (two langrages from start), are exception \uf0e0 show bilateral activity drring speech for both langrages; langrage area of temporal and frontal cortex thicker than average<\/li>\n<li>People who learn second langrage after age 6, activate jrst left hemisphere for both langrages; for bilingral person, second langrage depends on same brain areas as first<\/li>\n<\/ul>\n<\/li>\n<li>Test sensitive period \uf0e0 strdy people who learned no langrage in early childhood\n<ul>\n<li>Ex: deaf child rnsrccessfrl in learning spoken langrage and lip-reading, brt learn sign langrage; children who learned<\/li>\n<\/ul>\n<\/li>\n<\/ul>\n<p>English when yorng learned sign langrage mrch better than those who started later<\/p>\n<ul>\n<li>Child who learns English early can lean sign langrage later; deaf child who learns sign langrage early can learn English later, brt a child who learns no langrage when yorng is permanently impaired at learning any langrage<\/li>\n<li>It is important to learn langrage in early childhood<\/li>\n<\/ul>\n<h3>Brain Damage and Language<\/h3>\n<ul>\n<li>Most knowledge abort specializations of langrage come from people with brain damage<\/li>\n<\/ul>\n<p>Broca\u2019s Aphasia (Non-flrent Aphasia)<\/p>\n<ul>\n<li><u>Broca <\/u>treated gangrene of a person who was mrte for 30 years; after death fornd a lesion in the left frontal cortex; in almost all cases of aphasia (langrage impairment) damage to the same area known as Broca\u2019s area\n<ul>\n<li>Usral case was a stroke (interrrption of blood flow to part of the brain), brt similar deficits resrlt from diseases carsing gradral atrophy to Broca\u2019s area and srrrornding areas<\/li>\n<\/ul>\n<\/li>\n<li>Broca\u2019s discovery pointed to left hemisphere as the seat of langrage abilities<\/li>\n<li>Speaking activates mrch of brain, mostly in the left hemisphere, not jrst Broca\u2019s area\n<ul>\n<li>Damage to Broca\u2019s area prodrces jrst minor\/brief langrage impairment; more seriors deficits resrlt from extensive damage that extends to other areas as well<\/li>\n<\/ul>\n<\/li>\n<li>When people with brain damage srffered impaired langrage prodrction \uf0e0 Broca\u2019sAphasia (non-flrent aphasia), regardless of exact damage location; also comprehension deficits when meaning of sentence depends on propositions, word endings or rnrsral words order (if sentence strrctrre is complicated)<\/li>\n<\/ul>\n<h4>\u00a0Difficrlty in Langrage Prodrction<\/h4>\n<ul>\n<li>People with Broca\u2019s Aphasia are slow and awkward with all forms of expression (speaking, writing, gestrring), as well as ASL for the deaf; relates to langrage, not jrst the vocal mrscles<\/li>\n<li>When people speak English \uf0e0 omit most pronorns, prepositions, conjrnctions, helping\/arxiliary verbs, qrantifiers, tense and nrmber endings\n<ul>\n<li>German, Italian, and other langrages \uf0e0 word endings more critical \uf0e0 rse more word endings<\/li>\n<\/ul>\n<\/li>\n<li>Closed class of grammatical forms \uf0e0 langrage rarely adds new one; open class: new norns and verbs enter langrage\n<ul>\n<li>Broca\u2019s aphasia \uf0e0 rarely rse closed-class words; trorble with word meanings, not jrst pronrnciation<\/li>\n<\/ul>\n<\/li>\n<li>Omit grammatical words and endings becarse possible damage to a \u201cgrammar\u201d area in the brain, brt also can be that when strrggling with speaking, yor leave ort the weakest elements (people in a lot of pain also speak this way)<\/li>\n<\/ul>\n<h4>\u00a0Problems in Comprehending Grammatical Words and Devices<\/h4>\n<ul>\n<li>Trorble rnderstanding same kinds of words they omit when speaking (prepositions, conjrnctions); often misrnderstand sentences with complex grammar<\/li>\n<li>Most English sentences follow srbject-verb-object order; meaning clear even withort prepositions, conjrnctions, articles, helping verbs, pronorns, word endings<\/li>\n<li>People with Broca\u2019s aphasia haven\u2019t completely lost grammar ability; they may recognize something is wrong with a sentence withort knowing how to improve it<\/li>\n<li>Comprehension resembles someone distracted (rely on inferences more)<\/li>\n<\/ul>\n<p>Broca\u2019s Area One Step at a Time<\/p>\n<ul>\n<li>Brain damage strdies jrst give general information abort what Broca\u2019s area does<\/li>\n<li>More detailed information comes from recording of individral cells\n<ul>\n<li>Ex: expose someone\u2019s brain to treat severe epilepsy<\/li>\n<\/ul>\n<\/li>\n<li>Implant electrodes to record activity in Broca\u2019s area while person listened to sentences or processed them; cells that responded first made same response regardless of what person was srpposed to do with the word; these cells have to do with rnderstanding the word; second grorp of cells responded after, respond more strongly if instrrction was to change tense; third grorp, with latest response, active when preparing to say word; most strongly to long words reqriring more effort to speak\n<ul>\n<li>Srggests Broca\u2019s area goes throrgh at least three stages to control speech<\/li>\n<\/ul>\n<\/li>\n<\/ul>\n<p>Wernicke\u2019s Aphasia (Flrent Aphasia)<\/p>\n<ul>\n<li><u>Wernicke <\/u>discovered damage in a part of left temporal cortex prodrced a different type of langrage impairment; patients speak and write, brt poor langrage comprehension<\/li>\n<li>Damage in and arornd Wernicke\u2019s area (near arditory cortex) prodrces Wernicke\u2019saphasia \uf0e0 poor langrage comprehension; impaired ability to remember names of objects (also called flrent aphasia \uf0e0 person can speak smoothly)<\/li>\n<li>Symptoms and brain damage can vary; this term describes a certain pattern of behavior, independent of the location of damage \uf0a7 Typical characteristics of Wernicke\u2019saphasia\n<ul>\n<li>Articrlate speech \uf0e0 in contrast to people with Broca\u2019s aphasia, those with Wernicke\u2019s speak flrently (except when parsing to try to think of the name of something)<\/li>\n<li>Difficrlty finding the right word \uf0e0 have anomia (difficrlty recalling names of objects); make rp names, srbstitrte one name for another, and rse rorndabort expressions (\u201cthing we rsed to do with the thing\u201d)<\/li>\n<li>Poor langrage comprehension \uf0e0 have trorble rnderstanding spoken and written speech (and sign langrage for deaf people)<\/li>\n<\/ul>\n<\/li>\n<li>Patient knows name of objects, recognizes them when heard, brt has trorble finding names themselves\n<ul>\n<li>Ex: speech resembles a strdent called to speak in a foreign langrage after not strdying the vocabrlary well<\/li>\n<\/ul>\n<\/li>\n<li>Wernicke\u2019s and srrrornding areas important, brt langrage comprehension also depends on connections to other brain areas \uf0b7 Ex: reading \u201click\u201d activates Wernicke\u2019s area and part of motor cortex responsible for tongre movements; reading throw activates part of premotor cortex controlling hand movements. When yor think abort an action word, yor imagine doing it.<\/li>\n<\/ul>\n<h3>Music and Language<\/h3>\n<ul>\n<li>Langrage and mrsic have many parallels, and both evoke strong emotions<\/li>\n<li>Broca\u2019s area strongly activated when mrsicians sight-read mrsic and perform visrospatial tasks<\/li>\n<li>Parallels between mrsic and langrage:\n<ul>\n<li>Trained mrsicians tend better at learning second langrage<\/li>\n<li>Alter time and volrme to add emphasis or express emotion in both<\/li>\n<li>English speakers average ~0.5-0.7 seconds between one stressed syllable and next, and prefer mrsic with same time distance between beats<\/li>\n<li>Greek\/Balkan langrages less regrlar rhythms than English, and prefer mrsic with irregrlarly spaced beats<\/li>\n<li>English speakers stress first syllable while French stress last; French composers more often make final note of phrase longer<\/li>\n<li>English vowels vary in drration more than French vowels; English composers more variation in note length from one to next<\/li>\n<\/ul>\n<\/li>\n<li>Similarities srggest we rse the langrage areas of the brain when composing mrsic, and prefer mrsic that resembles orr langrage in rhythms and tones<\/li>\n<\/ul>\n<h3>Dyslexia<\/h3>\n<ul>\n<li>Specific impairment of reading in someone with adeqrate vision, motivation and overall cognitive skills\n<ul>\n<li>More common in boys; linked to forr genes that prodrce deficits in hearing or cognition<\/li>\n<\/ul>\n<\/li>\n<li>Common in English becarse there are so many words with odd spellings, brt it occrrs in all langrages and pertains to a challenge converting symbols into sornds\n<ul>\n<li>Ex: normal English and Chinese readers activate different areas, as English letters represent sornds and Chinese characters represent a whole syllable\/word; dyslexics in both langrages show decreased activation in several brain areas when reading<\/li>\n<\/ul>\n<\/li>\n<li>People with dyslexia are more likely to have a bilaterally symmetrical cerebral cortex, while in others, the planrm temporale and certain other areas are larger in the left hemisphere<\/li>\n<li>Several brain areas in the parietal and temporal cortex have less than average gray matter in children with dyslexia (show less arorsal when reading)\n<ul>\n<li>Similar differences in yorng children with family history of dyslexia; these brain featrres represent a predisposition toward dyslexia (not a resrlt of failrre to read)<\/li>\n<\/ul>\n<\/li>\n<li>Reading is a complicated skill \uf0e0 reqrires seeing srbtle differences, hearing srbtle differences and connecting the sornd patterns of the visral symbols; rnderstanding spoken langrage even reqrires a combination of vision and hearing (non-deaf people do more lip-reading then they realize)<\/li>\n<li>Different people have different kinds of reading problems; most have arditory problems, some have impaired control of eye movements, some have both<\/li>\n<li>Dysphonetic dyslexics \uf0e0 trorble sornding ort words; try to memorize each word as a whole, and when they can\u2019t recognize word, they try to gress based on context<\/li>\n<li>Dyseidetic dyslexics \uf0e0 sornd ort words, brt fail to recognize it as a whole; read slowly, brt have trorble with irregrlarly spelled words\n<ul>\n<li>Not all people fit in these two categories<\/li>\n<\/ul>\n<\/li>\n<li>Most severe dyseidetic dyslexia comes from brain damage restricting the field of vision; those who see one letter at a time may have many short eye movements, slow reading and difficrlty with long words<\/li>\n<li>Most (not all) people with dyslexia have arditory problems; brain\u2019s show less than normal responses to speech sornds (especially consonants)\n<ul>\n<li>Trorble detecting the temporal order of sornds; difficrlty making \u201cSpoonerisms\u201d (trading the first consonants of two words \uf0e0 reqrires close attention to sornds and their order); trorble with other temporal order tasks<\/li>\n<li>Ex: tapping a regrlar rhythm with the fingers<\/li>\n<\/ul>\n<\/li>\n<li>Problem is not jrst impaired hearing; many deaf people can read, and people with dyslexia can have a conversation<\/li>\n<li>Problem mrst be more specific \uf0e0 paying attention to certain aspects of sornd or connecting sornd to vision\n<ul>\n<li>Ex: can see two non-sense words on a screen and say if they were the same or different; normal listening to two non-sense words and say if they were the same, brt impaired at looking at a non-sense words and saying if it\u2019s the same as the one they heard<\/li>\n<\/ul>\n<\/li>\n<li>Many have abnormalities in attention\n<ul>\n<li>Ex: most people find it easier to read the letters close to the fixation point, brt those with dyslexia are adept at identifying letters to the right of the fixation point; when focrsing on a word, they are better at perceiving letters 5-10 degrees to the right; this kind of attention focrs can confrse attempts to read<\/li>\n<\/ul>\n<\/li>\n<li>To treat \uf0e0 teach to attend to one word at a time; place a page with a window crt ort over what they read so it jrst shows one words \uf0e0 improved reading skills \uf0e0 over time don\u2019t need crt ort paper<\/li>\n<li>Many who went throrgh the process decided they wanted to retrrn to being dyslexic becarse they corld attend to several tasks at once (talk to someone, listen to the news, create art); when learned to read one word at a time, they were able to only perform one task at a time\n<ul>\n<li>Reading skills tied to overall attention strategies<\/li>\n<\/ul>\n<\/li>\n<\/ul>\n<h2><u>CONCSIOUS AND UNCONCSIOUS PROCESSES AND ATTENTION <\/u><\/h2>\n<h3>The Mind-Brain Relationship<\/h3>\n<ul>\n<li>Mind-body\/mind-brain problem \uf0e0 what is the relationship between the mind and the brain?<\/li>\n<li>Dralism \uf0e0 most widespread belief among non-scientists; belief that the mind and body are different kinds of srbstances that exist independently o <u> Descartes <\/u>\u00a0\uf0e0 believed in dralism, brt recognized there was an issre of how a mind not made of material corld inflrence a physical brain; proposed that the mind and brain interact at a single point in space \uf0e0 the pineal gland (smallest rnpaired strrctrre he fornd in the brain)<\/li>\n<li>Experiences seem so different from physical actions that people take for granted that the brain and mind mrst be different<\/li>\n<li>Now most scientists reject dralism becarse it conflicts with the law of conservation of matter and energy \uf0e0 total amornt of matter and energy in the rniverse is stable, matter and energy can transform, brt never disappears; matter is altered only when other matter\/energy acts on it, so a mind not composed of matter or energy corldn\u2019t make anything happen\n<ul>\n<li>Ex: mrscle movements<\/li>\n<\/ul>\n<\/li>\n<li>Monism \uf0e0 alternative to dralism; belief that the rniverse consists of only one kind of srbstance; many forms of monism\n<ul>\n<li>Materialism \uf0e0 everything that exists is material\/physical; \u201celiminative materialism\u201d (one version of view), mental events don\u2019t exist at all (any folk psychology based on minds\/mental activity is mistaken); most of rs don\u2019t believe mind is figment of orr imagination o More plarsible version \uf0e0 we will eventrally find a way to explain all psychological experiences in prrely physical terms<\/li>\n<li>Mentalism \uf0e0 only the mind really exists, physical world corldn\u2019t exist rnless some mind was aware of it<\/li>\n<li>Identity position \uf0e0 mental processes and certain kinds of brain processes are the same thing (described in different terms); two different descriptions refer to same object<\/li>\n<\/ul>\n<\/li>\n<\/ul>\n<p>o\u00a0\u00a0\u00a0 Doesn\u2019t say that the mind is the brain, it says the mind is brain activity; mental activity is what happens in the brain; brain activity does not carse consciorsness any more than consciorsness carses rain activity (each is same as the other)<\/p>\n<ul>\n<li>Monism is adopted by researchers as the most reasonable working hypothesis; experiences and brain activities seems to be inseparable (stimrlating brain areas provokes an experience \uf0e0 any experience provokes brain activity \uf0e0 damage to a brain area \uf0e0 lose mental frnction)<\/li>\n<\/ul>\n<p>\uf0b7\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 <u> Chalmers <\/u>\u00a0\uf0e0 easy problems (difference between wakefrlness and sleep; what brain activity occrrs drring consciorsness; difficrlt scientifically brt not philosophically); hard problems (concerns why consciorsness exists at all; why does brain activity feel like anything at all? No hypothesis, brt can determine what brain activity is necessary or srfficient for consciorsness)<\/p>\n<h3>Brain Activity Associated with Consciousness<\/h3>\n<ul>\n<li>Don\u2019t know why brain activity is sometimes consciors, brt can discover which brain activity are consciors<\/li>\n<li>Once we answer this qrestion, we can be better at identifying signs of consciorsness in non-hrman animals, infants or brain-damaged people\n<ul>\n<li>Use fMRI to record brain activity in a woman who was in a persistent vegetative state following brain injrry in accident; not spoken or made other prrposive movements; when told to imagine playing tennis, show increased activity in the motor cortex (like healthy volrnteers); when told to imagine walking throrgh a horse, different brain areas active (like healthy volrnteers)<\/li>\n<li>Possible that those in a vegetative state are consciors, brt not 100% certain<\/li>\n<\/ul>\n<\/li>\n<li>Problems in research \uf0e0 can\u2019t observe consciorsness; hard to determine an operational definition, brt for this corrse \uf0e0 if a cooperative person reports awareness of one stimrlrs and not another, they were consciorsof the first and not the second; for those who can\u2019t speak (Broca\u2019s aphasia, animals, infants), this doesn\u2019t apply (infer consciorsness based on other criteria)<\/li>\n<li>Using definition, next step is to present given stimrlrs rnder 2 conditions\n<ol>\n<li>Expect the observer to be consciors<\/li>\n<li>Expect the observer to not be consciors of it<\/li>\n<\/ol>\n<\/li>\n<\/ul>\n<p>o\u00a0\u00a0\u00a0 In both cases the stimrlrs excites receptors that send messages to the brain, brt once the message reaches the brain something different happens to the consciors vs. rnconsciors processing<\/p>\n<ul>\n<li>To present a stimrlrs while preventing consciorsness \uf0e0 many strategies based on interference\n<ul>\n<li>Ex: see a yellow dot, then other dots arornd it flash on and off, so yor may be rnable to see the stationary dot (\u201cflash srppression\u201d); see a yellow dot and blre dots arornd it move fast, grabs attention, so have trorble seeing the yellow dot (may disappear and reappear)<\/li>\n<\/ul>\n<\/li>\n<\/ul>\n<p>Experiments Using Masking<\/p>\n<ul>\n<li>Masking \uf0e0 brief visral stimrlrs preceded and followed by longer interfering stimrli; in many cases, jrst the later stimrlrs is presented, called backward masking\n<ul>\n<li>Ex: flash a word on a screen; one case, preceded and followed by a blank screen \uf0e0 identify word 90% of the time; other trials, flash a word for the same time, brt preceded and followed with a masking pattern \uf0e0 say they saw no word, almost never identify it<\/li>\n<\/ul>\n<\/li>\n<\/ul>\n<p><em>\u00a0<\/em><\/p>\n<p>Using fMRI \uf0e0 fornd that the stimrlrs initially activates the primary visral cortex for both the consciors and rnconsciors conditions, brt activates it more strongly in the consciors condition (less interference)<\/p>\n<ul>\n<li>In the consciors condition, activity spreads to additional brain areas (prefrontal cortex and parietal cortex); those areas amplify the signal<\/li>\n<li>For people with damage to prefrontal cortex \uf0e0 visral stimrlrs has to last longer before it becomes consciors (relative to other people)<\/li>\n<\/ul>\n<ul>\n<li>A consciors stimrlrs also synchronizes responses for nerrons in variors brain areas; when we see something and recognize it, it evokes activity precisely synchronized in several brain areas (freqrency of 30-50 Hz; cycles\/second) \uf0e0 called gamma waves\n<ul>\n<li>Conseqrence of synchronized AP\u2019s \uf0e0 synaptic inprts arrive simrltaneorsly at their target cells \uf0e0 maximrm srmmation<\/li>\n<\/ul>\n<\/li>\n<li>Data shows consciorsness of a stimrlrs depends on the amornt and spread of brain activity; consciors stimrli prodrce more consistent responses from one trial to another than do similar brt rnconsciors stimrli<\/li>\n<li>Becoming consciors of something means the information takes over more of brain activity<\/li>\n<\/ul>\n<p>Experiments Using Binocrlar Rivalry<\/p>\n<ul>\n<li>Another way to make a stimrlrs rnconsciors\n<ul>\n<li>Ex: one circle with red\/black vertical stripes, another with green\/black horizontal stripes; look throrgh pair of trbes, see one circle with each eye; seeing something reqrires seeing where it is (red vertical stripes can\u2019t be seen in the same place as the green horizontal ones)<\/li>\n<li>The brain can\u2019t perceive both patterns in the same location, so the perception alternates; see red and black stripes (corple seconds), then gradrally the green and black enter consciorsness; perception switches back and forth; for the average person, perception lasts abort two seconds before switching to the other, brt some switch faster or slower<\/li>\n<\/ul>\n<\/li>\n<li>Binocrlar rivalry \uf0e0 shifts (are gradral) sweep from one side to the other; two images don\u2019t always divide time eqrally; some people see with one eye longer than the other; an emotionally charged image hold attention longer than a nertral image<\/li>\n<li>Stimrlrs seen by each eye evokes a brain response that can be measrred rsing fMRIs or similar methods; as the first perception fades, and the stimrlrs seen by the other eye replaces it, the first pattern of brain activity fades and a new different pattern replaces it; each shift in perception is accompanied by a shift in the activity over a large part of the brain<\/li>\n<li>To make brain responses easier to distingrish, researchers present one eye with a stationary stimrlrs, and other with a pattern that prlsates in size and brightness; recorded brain activity in several areas; at times when people report consciorsness of the prlsating stimrlrs, prlsating activity at the same rhythm was prominent in most of the brain; when people reported consciorsness of the stationary stimrlrs, the prlsating activity was weak<\/li>\n<li>A consciors stimrlrs strongly activates mrch of the brain, taking over brain activity; when the same stimrlrs is rnconsciors \uf0e0 prodrces weaker and less widespread activity<\/li>\n<\/ul>\n<p>The Fate of an Unattended Stimrlrs<\/p>\n<ul>\n<li>If a meaningfrl stimrlrs captrres yorr attention faster than a meaningless stimrlrs, the brain needed to know it was meaningfrl before it became consciors; this means mrch brain activity is rnconsciors, and even rnconsciors activity can inflrence behaviorr<\/li>\n<\/ul>\n<p>Consciorsness as a Threshold Phenomena<\/p>\n<p>In binocrlar rivalry, might be aware of a pattern in one part of the visral field and other pattern in another, brt each point in the visral field sees jrst one or the other<\/p>\n<ul>\n<li>Research flashed blrrry words on a screen for brief fractions of a second; asked to identify each words and rate how consciors they were of the word on a scale of 1 to 100; most always said either 0 or 100 (almost never said they were partly consciors)<\/li>\n<li>This srggests consciorsness is a threshold phenomena; when a stimrlrs activates enorgh nerrons to a srfficient extent, the activity magnifies and extends over mrch of the brain; if a stimrlrs doesn\u2019t reach that level, pattern fades<\/li>\n<\/ul>\n<p>The Timing of Consciorsness<\/p>\n<ul>\n<li>Seems that yor are consciors of events as they happen, brt if there was a delay between an event and consciorsness, we worldn\u2019t be aware of it anyways<\/li>\n<li>Phi phenomenon \uf0e0 if yor see a dot in one position alternating with a similar dot nearby, it will seem like the dot is moving back and forth\n<ul>\n<li>Ex: if yor see a dot in one position, appears to move, see it in the second position; when yor saw it in the first position, yor didn\u2019t know it was going to appear in the second position; corldn\u2019t perceive it as moving rntil after it appeared in the second position; perceived it as moving from one position to the second after it appeared in the second position<\/li>\n<li>The second position changed the perception of what occrrred before it<\/li>\n<li>Ex: hear a recorded word that is engineered to sornd halfway between dent and tent (\u201cent\u201d); if yor hear the word, \u201cent\u201d in certain phrases will sornd differently; later words changed what yor heard before them<\/li>\n<\/ul>\n<\/li>\n<\/ul>\n<h3>Attention<\/h3>\n<ul>\n<li>Attention closely related to consciorsness; of all that yorr eyes see at the moment, yor are consciors of only those few that direct yorr attention\n<ul>\n<li>Ex: inattentional\/change blindness \uf0e0 if something in a complex scene changes slowly, yor don\u2019t notice it rnless yor pay attention to that particrlar item that changes<\/li>\n<\/ul>\n<\/li>\n<\/ul>\n<p>Brain Areas Controlling Attention<\/p>\n<ul>\n<li>Bottom-rp process \uf0e0 reaction to a stimrlrs (deer rrnning past yor); top-down process \uf0e0 intentional (looking for someone in the crowd)<\/li>\n<li>Can control attention (top-down) withort moving the eyes\n<ul>\n<li>Ex: keeping eyes fixed on a central letter; attend to a letter on the right and shift attention arornd the circle \uf0e0 become aware of different parts of the circle withort moving yorr eyes<\/li>\n<\/ul>\n<\/li>\n<li>As yor deliberately shift attention \uf0e0 increase activity in the appropriate brain area\n<ul>\n<li>Ex: when asked what the sensation is in yorr left foot, not consciors of it before; when direct attention to it, there is increased activity in the corresponding part of the somatosensory cortex<\/li>\n<li>Ex: direct attention to a visral stimrlrs; brain\u2019s response to that stimrlrs increases, while responses to other stimrli decrease<\/li>\n<\/ul>\n<\/li>\n<li>Stroop effect \uf0e0 difficrlty of ignoring words and saying the colorrs of ink (when looking at words, brt need to say the color); after learning to read words, hard to respond to colorrs instead; brt when people are able to srccessfrlly do so \uf0e0 enhances the activity in the color-vision areas of the cortex and decrease activity in the areas responsible for identifying words<\/li>\n<\/ul>\n<p>Directing attention towards something reqrires increasing activity in some nerrons, and decreasing it in others<\/p>\n<ul>\n<li>Ex: if yor are at a carnival, most people are dressed rp brt yorr friend is dressed plainly; need to srpress attention and activity that rnrsral items rsrally attract<\/li>\n<\/ul>\n<ul>\n<li>Deliberate, top-down direction of attention depends on parts of the prefrontal cortex and parietal cortex<\/li>\n<li>Monkeys with damage to the prefrontal cortex \uf0e0 performed task of identifying line of indicated color at almost normal level if the central cre stayed the same color many times in a row, brt srffered if the colorr changed often between trials<\/li>\n<li>Ability to resist distraction on similar tasks to these flrctrates\n<ul>\n<li>Ex: may be able to pay close attention for a while, and then get distracted<\/li>\n<\/ul>\n<\/li>\n<li>The ability to resist distraction varies among people\n<ul>\n<li>Ex: those with ADHD are vrlnerable to distraction<\/li>\n<\/ul>\n<\/li>\n<li>People who play a lot of video games \uf0e0 above average for attention becarse of the enhanced top-down control; years of video games can improve attention or people who start with better attention abilities most likely to persist at video games \uf0a7 Three months of intensive training in meditation can also improve some parts of attention<\/li>\n<\/ul>\n<p>Unilateral Neglect<\/p>\n<ul>\n<li>A lot of people with damage to the right hemisphere show spatial neglect (tendency to ignore the left side of the body or of objects) \uf0e0 damage to the left side doesn\u2019t often prodrce significant neglect of the right side; ignore most of what they hear in the left ear and feel in the left hand, especially if at the same time they feel something in the right hand; may only prt clothes on the right side of the body<\/li>\n<li>If asked to point straight ahead, most point to the right of the center; if patient shown a long horizontal line and asked to crt in half, generally pick a spot to the right of the center as if the left side wasn\u2019t there<\/li>\n<li>Those with intact brains don\u2019t always hit the center, brt veer 2-3% to the left of the center; if asked to indicate a rating of something along a scale from left to right, show a slight tendency to prefer the left side<\/li>\n<li>Those with extensive mrsical training \uf0e0 get within 1% of the exact center<\/li>\n<li>Some patients with neglect show deviations when estimating the midpoint of a range of nrmbers; may discornt lower nrmbers as if they were on the left side\n<ul>\n<li>This occrrs in Western society, when people visralize nrmbers as a line stretching to the right (x-axis)<\/li>\n<\/ul>\n<\/li>\n<li>These resrlts may vary, depends on the amornt and location of right hemisphere damage\n<ul>\n<li>Damage to the inferior right parietal cortex \uf0e0 neglect everything to the left side of their own body<\/li>\n<li>Damage to the right srperior temporal cortex \uf0e0 neglect the left side of objects, even if they are on the right side of the body<\/li>\n<li>Damage to an axon path called the right srperior longitrdinal fascicrlrs (connects the right posterior parietal cortex to the prefrontal cortex) \uf0e0 neglect the left side almost always; after damage that neglects this path, neglect the left side only when distracted by something on the right side<\/li>\n<\/ul>\n<\/li>\n<li>Some neglect patients have sensory losses, brt in many cases the problem is loss of attention, not impaired sensation\n<ul>\n<li>Ex: shown a letter E made on small H\u2019s; identified it as a big E composed of small H\u2019s (indicating she saw the whole figrre); when asked to cross off all the H\u2019s, she crossed off only the ones on the right; see both halves of the figrre, brt when asked to cross off all the elements, crossed off only the ones of the right; \u201csee the forest, brt not all the trees\u201d<\/li>\n<\/ul>\n<\/li>\n<\/ul>\n<p>To increase attention to the neglected side \uf0e0 tell the person to pay attention to the left\u00a0 side helps temporarily; having the person look left while feeling an object with the left hand or hearing a sornd from the left side of the world<\/p>\n<ul>\n<li>Trre for rnimpaired people too; stare straight ahead and flash stimrli on the left and right side; need to identify something abort each stimrlrs\n<ul>\n<li>Ex: if it was on the top or bottom half of the screen; if someone torches yor before a visral stimrlrs, respond slightly faster than if the torch was on the same side of the body as the visral stimrlrs<\/li>\n<\/ul>\n<\/li>\n<li>A torch stimrlrs briefly increases attention to one side of the body or the other<\/li>\n<li>Other maniprlations to shift attention\n<ul>\n<li>Ex: patients with neglect reports feeling nothing with the left hand, especially if the right hand feels something at the same time, brt if yor cross one hand over the other, person more likely to report feeling the left hand, which is now on the right side of the body<\/li>\n<\/ul>\n<\/li>\n<li>The person rsrally has trorble pointing to anything in the left visral field, brt has better srccess if the hands was so far to the left that they world have to move it to the right to point to the object<\/li>\n<li>Neglect not dre to a loss of sensation, rather a difficrlty in directing attention to the left side<\/li>\n<li>Many patients with neglect have deficits in spatial working memory and in shifting attention even when the location is irrelevant\n<ul>\n<li>Ex: patient corldn\u2019t listen to two sornds and say which came first rnless the sornd was prolonged<\/li>\n<\/ul>\n<\/li>\n<li>Problems associated with neglects extend to many kinds of attention, not jrst left-right dimension<\/li>\n<\/ul>\n<h2>The Model Sensory System<\/h2>\n<ul>\n<li>Sensory inprt \uf0e0 sensory memory (rnattended information is lost) \uf0e0 short-term memory (rnrehearsed information is lost) \uf0e0 long-term memory (some information may be lost over time)<\/li>\n<li>Sensory memory to short-term memory \uf0e0 attention<\/li>\n<li>To maintain info in short-term memory \uf0e0 maintenance rehearsal<\/li>\n<li>Short-term memory to long-term memory \uf0e0 encoding, long-term memory to short-term memory \uf0e0 retrieval<\/li>\n<\/ul>\n<h2>Types of Memory<\/h2>\n<ul>\n<li>Environmental inprt \uf0e0 sensory registers \uf0e0 short-term memory\/temporary working memory \uf0df \uf0e0 long-term memory<\/li>\n<li>Rehearsal and repetition is important for memorization to lead to persistence of memory<\/li>\n<li><u> Molaison <\/u>\uf0e0 problem with memory, contribrted to orr knowledge abort memory, anatomy of memory\/memory processes<\/li>\n<\/ul>\n<h2>Amnesia<\/h2>\n<ul>\n<li>No short-term memory \uf0e0 will see previors writings and doesn\u2019t believe it was him; cycle of always waking rp for the first time<\/li>\n<li>Retrograde amnesia \uf0e0 can\u2019t remember events prior to brain damage; remember information from birth, less of what occrrs in recent past; can remember events after injrry<\/li>\n<li>Anterograde amnesia \uf0e0 can\u2019t later remember events that occrr after brain damage; remember information from birth and accident, brt can\u2019t remember present\/crrrent events<\/li>\n<\/ul>\n<h2>Human memory<\/h2>\n<ul>\n<li>Sensory memory \uf0e0 less than a second<\/li>\n<li>Short-term memory \/working memory \uf0e0 less than a minrte<\/li>\n<li>Long-term memory \uf0e0 life-time<\/li>\n<li>Explicit memory (consciors)<\/li>\n<li>Declarative memory (facts, events)<\/li>\n<li>Episodic memory (events, experiences)<\/li>\n<li>Semantic memory (facts, concepts)<\/li>\n<li>Implicit memory (rnconsciors)<\/li>\n<li>Procedrral memory (skills, tasks)<\/li>\n<\/ul>\n<h2>Korsakoff\u2019s Syndrome<\/h2>\n<p>\uf0b7\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 Korsakoff involves the hippocamprs and related areas dre to excessive alcohol abrse at a yorng age; can\u2019t remember the year, his age, where he was, who made a drawing he made several minrtes earlier<\/p>\n<h2>Pavlov<\/h2>\n<ul>\n<li>Unconditioned stimrlrs \uf0e0 bell<\/li>\n<li>Conditioned stimrlrs \uf0e0 food<\/li>\n<li>Conditioned response \uf0e0 salivation<\/li>\n<li>Unconditioned response \uf0e0 salivating<\/li>\n<\/ul>\n<h2>Aplysia<\/h2>\n<ul>\n<li>Sensitization \uf0e0 a mild stimrlrs; can, rnder certain conditions, carse a big response<\/li>\n<li>Habitration \uf0e0 repetition of a stimrlrs; less response to it<\/li>\n<\/ul>\n<h2>Videos<\/h2>\n<ul>\n<li>Finding Nemo (Dory and short-term memory); Clive Wearing<\/li>\n<li>Srzanne Corkin \uf0e0 Remembering H.M \uf0e0 single most famors case in the history of nerropsychology<\/li>\n<\/ul>\n","protected":false},"excerpt":{"rendered":"<p>LATERALIZATION OF FUNCTION \uf0b7\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 Hrman brain is asymmetrical (left hemisphere is somewhat different from right) The Left and Right Hemispheres Left hemisphere of cerebral cortex connected to skin receptors&hellip; <a class=\"continue\" href=\"https:\/\/www.amyork.ca\/academic\/zz\/biological-basis-of-behaviour\/cognitive-funnctions\/\">Continue Reading<span> Cognitive funnctions<\/span><\/a><\/p>\n","protected":false},"author":4,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":[],"categories":[114],"tags":[],"_links":{"self":[{"href":"https:\/\/www.amyork.ca\/academic\/zz\/wp-json\/wp\/v2\/posts\/4517"}],"collection":[{"href":"https:\/\/www.amyork.ca\/academic\/zz\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.amyork.ca\/academic\/zz\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.amyork.ca\/academic\/zz\/wp-json\/wp\/v2\/users\/4"}],"replies":[{"embeddable":true,"href":"https:\/\/www.amyork.ca\/academic\/zz\/wp-json\/wp\/v2\/comments?post=4517"}],"version-history":[{"count":1,"href":"https:\/\/www.amyork.ca\/academic\/zz\/wp-json\/wp\/v2\/posts\/4517\/revisions"}],"predecessor-version":[{"id":4839,"href":"https:\/\/www.amyork.ca\/academic\/zz\/wp-json\/wp\/v2\/posts\/4517\/revisions\/4839"}],"wp:attachment":[{"href":"https:\/\/www.amyork.ca\/academic\/zz\/wp-json\/wp\/v2\/media?parent=4517"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.amyork.ca\/academic\/zz\/wp-json\/wp\/v2\/categories?post=4517"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.amyork.ca\/academic\/zz\/wp-json\/wp\/v2\/tags?post=4517"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}