L6:FUNCTIONAL AREAS OF CEREBRAL CORTEX Flashcards
PRIMARY MOTOR AREA # Location Functions Lesion
PRIMARY MOTOR AREA #4 Location: precentral gyrus Functions: isolated movement of simple nature without much skill Lesion: hemiplegia, UMNL +Babinski
SUPEROLATERAL SURFACE OF PRIMARY MOTOR AREA
Controls
Supplied by
Effect of occlusion
SUPEROLATERAL SURFACE
Controls: muscles above knee of contralateral side
Supplied by: Middle Cerebral Artery
Occlusion: contralateral paralysis of muscles above the knee.
MEDIAL SURFACE OF PRIMARY MOTOR AREA
Controls
Supplied by
Effect of occlusion
MEDIAL SURFACE
Controls: contralateral muscles below the knee
Supplied by: ANTERIOR CEREBELLAR ARTERY
Effect of occlusion: paralysis of contralateral muscles below the knee.
PREMOTOR AREA #s Location Functions; general and by number Lesion
PREMOTOR AREA
Location: Superior, middle, inferior frontal gyri
Functions: program movements executed by area 4, corpus striatum, cerebellum
Upper part of 6: writing center
8(frontal eye field): regulate voluntary conjugate movement(bilateral fixation on object)
Lesion: hesitancy in performing learned movements.
Corpus striatum?
Collective name for caudate nucleus and lentiform nucleus within basal ganglia
A lesion in internal capsule leads to:
TOTAL hemiplegia
Functions:
PREFRONTAL AREA
Lesion:
PREFRONTAL AREA #9 to 12
Functions:
- Regulate depth of feeling
- Abstract thinking, mature judgment and tactfulness
- Right vs wrong, pleasure vs displeasure
Lesion: mental with lack of responsibility, vulgarity and clownish behavior.
MOTOR AREAS
Primary 4
Premotor 6,8
Prefrontal 9 to 12
Supplementary
SENSORY AREA ORGANIZATION
A. PRIMARY
a. Somesthetic
b. Visual
c. Auditory
B. Secondary ( lower part of pre and post central gyrus- pain)
C. Association ( superior parietal lobule and AREA 40 AND 39)
PRIMARY SOMESTHETIC AREA
#
Location
Functions; general and by area
PRIMARY SOMESTHETIC AREA # area 3, 1 &2
Location: POST central gyrus
Functions: differentiates sensory modalities
Area 3: cutaneous sensation- touch, pressure, vibration
Area 1: cutaneous and joint senses
Area 2: DEEP sense from muscles and joints
Function of paracentral lobule and its blood supply
Function:Motor AND sensory control of lower limbs (below knees) and voluntary control of micturition and defecation.
Supplied by: ANTERIOR CEREBRAL ARTERY
PRIMARY VISUAL AREA AKA: # Location Structure
PRIMARY VISUAL AREA
AKA: striate area
#17 (followed by area 18, 19 39)
Location: lips & walls of posterior part of calcrine sulcus
Structure: very thin grey matter made of outer band of ballarger (layer 4) where pyramidal cells are replaced by STELLATE (sensory) cells.
PRIMARY VISUAL CORTEX
The optic tract in the superior colliculus ends in the Lateral Geniculate Nucleus of the thalamus ie. area 17.
In the optic chiasma, one eye will receive its ipsilateral temporal vision and the contralateral nasal vision.
MACULAR VISION
Function
Location
Blood supply
Function:central vision of max discrimination
Location:Projected onto area 17 (1/3 of visual cortex)
Blood supply: MIDDLE CEREBRAL ARTERY
Lesion of posterior cerebellar artery results in
Homonymous hemianopia in both eyes with sparing of macular vision as it is supplied by middle cerebellar artery.
