Cerebral hemispheres Flashcards
what are the general features of the cerebral hemispheres
sulcus - dip
gyrus - elevation
fissure - larger dip
grey matter on surface
white matter inside
lateral ventricle in the cavity of each hemisphere
what is the name of the fissure that runs down the centre of the cerebrum from front to back
median longitudinal fissure
what connects the right and left cerebral hemispheres
the corpus callosum - contains commissural fibres
what is the name of the sulcus that runs across the top of the cerebrum left to right and what lies on either side
central sulcus
in front - precentral gyrus
behind - post central gyrus
what does the central sulcus separate
parietal lobe from the frontal lobe
what separates the parietal and occipital lobes
parieto-occipital sulcus
what does the cingulate sulcus separate
parietal and frontal lobes from the cingulate gyrus
what does the lateral sulcus (sylvan fissure) separate
parietal and frontal lobes above from temporal lobe below
what is the posterior part of the cerebrum for
sensory
parietal - somatosensory
occipital - vision
temporal - hearing and smell
what is the anterior part of the cerebrum for
motor
frontal - motor function and intellect
what are the medial portions of the brain for
limbic system - storage and retrieval of processed information
within the frontal lobe - what are three important areas
area 4 - precentral gyrus
area 44,45 - inferior frontal gyrus
prefrontal cortex
what happens in area 4 of the frontal lobe
precentral gyrus = PRIMARY MOTOR CORTEX
somototopic representation of contralateral half of the body
what happens in areas 44,45 of the frontal lobe
inferior frontal gyrus = BROCAS AREA
motor speech
what happens in the prefrontal cortex
cognitive functions of higher order intellect
judgement
prediction
planning
within the parietal lobe - what are 3 important areas
areas 1,2,3 - post central gyrus
superior parietal lobule
inferior parietal lobule
what happens in areas 1,2,3 of the parietal lobe
post-central gyrus = PRIMARY SENSORY CORTEX
recieves general sensations from contralateral half of body
what happens in the superior parietal lobule
interpretation of general sensory info and conscious awareness of contralateral half of body
what happens in the inferior parietal lobule
interface between somatosensory cortex and visual and auditory association areas
in dominant hemisphere = contributes to language functions
what can occur if there is a lesion in the parietal lobe
hemisensory neglect
right-left agnosia
acalculia
agraphia
what is hemisensory neglect
the inability of a person to process and perceive stimuli on one side of the body or environment, where that inability is not due to a lack of sensation