Cerebral Cortex Flashcards
What embryonic structure is the cerebral cortex derived form?
telencephalon
What are the 6 lobes of the cerebral cortex?
Frontal, Parietal, Temporal, Occiptal, Limbic and Insula
6 layers of the neocortex from most superficial to deep?
molecular, external granular, external pyramidal, internal granular, internal pyramidal, multiform layer
What is the functional unit of the cortex?
Column that extends through 6 layers, columns form modules. Can be interconnected within the same hemisphere of between the two hemispheres
Which Brodmann’s Areas are the somatosensory cortex (postcentral gyrus)?
3,1,2
Which Brodmann’s Area is the primary motor cortex (precentral gyrus)?
4
Which Brodmann’s Area is the primary visual cortex (Cuneus and Lingual gyrus)?
17
Which Brodmann’s areas are the auditory cortex (Transverse gyri of Heschl)?
41, 42
Which Brodmann’s areas are the motor area of speech (Broca’s
44, 45
Lesion of primary somatosensory cortex
contralateral loss of somatic sensation
Which areas have greater representation somatopic representation in the somatosensory and motor cortices?
face and hand
What part of the body is medial is the somatosensory cortex and motor, and most lateral?
lower limb most medial, pharynx and tongue most lateral
Lesion of the primary motor cortex
contralateral spastic paralysis
Lesion of the visual cortex
contralateral hemianopia
If a lesion of the visual cortex is restricted to the upper banks of the calcarine fissure what would be the lesion? lower banks?
contralateral inferior quadrantanopia
contralateral superior quadrantanopia
Describe visuotopic organization of the visual cortex
Central VF most posterior, peripheral visual field most anterior
For the primary auditory cortex, which side is represented?
binaural representation, you need bilateral lesions for loss of hearing
Which side is Broca’s area generally more dominant?
left side
What is Broca’s aphasia?
Expressive aphasia- loss of the ability to produce fluent language (not dysarthia, not a motor problem)
What happens of there is a lesion of the non-dominant (generally right) side of 44/45 Broca’s
difficulty in expressing emotional aspect of language
What the 7 divisions of the frontal lobe?
primary motor, premotor, supp. motor, frontal eye field, Broca’s, prefrontal cortex (dorsolateral for working memory), limbic orbitofrontal cortex
Lesion of the parietal association cortex on dominant side (left)?
astereognosis, aphasia, alexia and agraphia (reading and writing)
these involve areas 39/40 (supramarginal and angular gyri)
Lesion of parietal association cortex on non-dominant (right) hemisphere?
spatial distortion and contralateral neglect
Where is Wernicke’s area and what is it for?
post. part of the sup. temp. gyrus (22), for language comprehnsion
Describe Wernicke’s Aphasia
dominant side: sensory or receptive aphasia–
person is unaware their words have no meaning but grammar is fluent
nondominant side: difficulty comprehending the emotional aspect of language
General functions of the cortex
- Special sensory perception
- Somatic sensory representation
- Planning/execution of voluntary movement
- Emotion/behavior
- Mental function
- Memory
What causes dysfunction of the cerebral cortex?
Vascular hemmorhage, thrombosis, or tumor usually of glial origin
