Hemispheric Asymmetry

a language deficit following brain damage or disease; appears RARELY in patients with damaged right hemisphere; signs of R brain lesions are more subtle, for ex. with prosody, or semantic cues

neurological syndrome characterized by loss of skilled or purposeful movement (not from weakness or inability to innervate muscles)

when injections of amobarbital (amytal) into the carotid artery produces an anesthesia of the ipsilateral hemisphere; ex: if you paralyze the L hemisphere, while you give person a spoon, then ask what you gave them they say nothing; if you show them a series of pictures, they will pick out the spoon (R hemisphere is still functioning, just can't speak

largest fiber system that connects the two cerebral cortices; contiains homotopic, heterotopic and ipsilateral areas; when severed many spatial abilities are lost

just kNOW that control is contralateral: SO if something is presented on the L side (or R hemisphere) then the patient will NOT be able to vocalize it but they can pick it out using their left hand; if something is presented to the R side (L hemisphere) then they can vocalize it and pick it out with their R hand

exactly what they sound like; specific examples include: describing that an object is a house (global) and then describing its specific [local] features (doors, windows, patterning). Another is Navon's letters made out of letters test

a configuration that may be described at multiple levels, from global features to local features; the finer components are embeded within the higher level components

local; global. This demonstrates the left hemisphere is better with local information and the right hemisphere is better with global information

the middle drawing was made by a patient with RIGHT hemispheric damage, because the local analysis is intact but the global one is not (local is controled by the [intact] L hemisphere and global is controled by the [lesioned] R hemisphere; opposite is true for the far right figure

the hypothesis that the two hemispheres differ in how they process complex information, with the left hemisphere biased toward processing high frequency information and the right hemisphere biased toward processing low frequency information

HIGH, Low; this means that a figure with a lot of individual 'bars' in it should show high activity in the LEFT hemisphere while a figure with less periodicity or fewer bars should show activation in the RIGHT hemisphere

a stimulus in which high frequencies are removed; a global shape persists even though local elements can't be distinguished (ex: blurry F, figure b)

low frequencies are removed; here both global and local elements can be identified but there isn't a lot of contrast (so like gray on gray)

uh oh

right hemisphere ------ left hemisphere; all you have to remember is Low/LVF: low frequency, left visual field (so therefore right hemisphere)

a manner of representing the spatial information of objects; specifies the exact positions of the objects and the distances between them; essential for action (Ex: picking up a glass of wine from a coffee table, you're not just going to grope around for it)

a manner of representing the spatial information of objects that captures the basic relational information such as the relative position of two objects from a particular viewpoint; useful for classifying objects using spatial information (ex: the letters b, d, p, q)

• Memory- verbal left/spatial bilateral Social/emotional- right hemisphere
• Motor – handedness/footedness/eyedness