Chapter 11 Flashcards
Laterality
Two cerebral hemispheres have separate functions
Relative but not absolute
Left hemisphere
Producing and understanding language
controlling movement on the right side of the body
Right hemisphere
Perceiving and synthesizing nonverbal information
Controlling movement on the left side of the body
Cerebral cite vs side
Cite as least as important in understanding brain function as cerebral side
Which larger and heavier?
Which more grey matter?
Wernicke’s and Heschl’s ?
Right - larger and heavier
Left - more grey matter
Wernicke’s larger in the left
Heschl’s gyrus larger in right
Anatomical asymmetry in the temporal lobes
Correlates with an asymmetry in the thalamus
Slope of lateral fissure
Less steep on left
Broca’s area
Organized differently on left vs right
Neurotransmitters
Distributed differently
Extending of the hemispheres
Right extends further anteriorly
Left extends further posteriorly
Neuronal asymmetry
Neurons in homologous regions of the right and left hemispheres have distinct patterns of dendritic branching
Double dissociation
The functions of two brain areas are dissociated by identifying performance deficits on two tasks. A lesion in one region causes a deficit on one task but not hte other; the second region causes the inverse pattern
Commissurotomy
Procedre that disconnects the two hemispheres by severing the corpus callosum
Allows the function of each hemisphere to be investigated independently
Brain stimulation
Right hemisphere has perceptual functions not shared by the left
Stimulating left frontal or temporal region may accelerate speech production
Stimulation blocks function
Carotid sodium amobarbital
Produces a brief period of anesthesia of the ipsilateral hemisphere
Allows each hemisphere to be studied independently in a relatively non-invasive manner
