Frontal and Occipital Lobes

Frontal lobe functions

motor output, inhibition, organization and planning

frontal lobe testing

simple motor tests, learning patterns with hands (mental set), mental flexibility, impulse control, novel problem solving, planning/organization, attention/mental control, emotional control, encoding/learning/retrieval of information, eye movements, concept formation

Frontal lobe functions

motor output, inhibition, organization and planning

frontal lobe testing

simple motor tests, learning patterns with hands (mental set), mental flexibility, impulse control, novel problem solving, planning/organization, attention/mental control, emotional control, encoding/learning/retrieval of information, eye movements, concept formation

motor strip (precentral gyrus)

execute behavior, corresponds to sensory area in sensory strip (postcentral gyrus), contralateral control

premotor cortex

anterior to motor strip, organizes motor plans, relays plans to motor cortex

prefrontal cortex

anterior to premotor cortex, sensory info sent here acts as starting point for movement, decides there will be movement

frontal lobe dorsolateral damage

pseudodepression (flat affect, apathetic, lack of initiation); small vessel disease, delirium

orbitofrontal damage

pseudopsycopathy - failure to inhibit, aggression, large personality shift, can be caused by aneruysm

ADHD

arousal comes from brainstem, travels through midbrain and white matter to frontal lobe (involved in inhibition) , DA agonists treat to stimulate inhibition

Frontotemporal Dementia

two variants: Language - cellular, stammering, halted speech, word-finding; behavioral - lability, apathetic type, no medical treatment

hemiparesis

lose use of half of body

frontal lobes and memory

learning and encoding, retain after delay, perseveration/intrusion, sensitivity to interference, difficulty with retrieval

Occipital lobe

vision

occipital lobe tests

visual confrontation/visual fields, double visual stimulation, all visual/visual-spatial tasks

calcarine cortex

primary visual cortex, all visual info goes here, if taken out = cortical blindness

eye lens

inverts images, flipped later in calcarine cortex, 50/50 contralateral processing

right lobe receives

nasal right eye and temporal left eye

left lobe receives

nasal left eye and temporal right eye

optic chiasm

point at which optic nerve fibers cross in the brain

vision path

eye, optic chiasm, optic track, LGN, optic radiations go through temporal and parietal, occipital lobe, calcarine cortex

feet

parietal

head

temporal

cerebral blindness

damage to occipital lobes, extremely rare, total loss of vision

eye blindness

lesion to single optic nerve results in not seeing out of that eye

optic chiasm damage

bitemporal hemianopia (don't see temporal field, hallway vision)

homonymous hemianopia

only see on half of space (right lesion, see only right, left lesion, see only left) C & D on figure

quadrantic hemianopia

lose a quadrant of vision (lesions at E & F on figure)

magnocellular

movement and depth

parvocellular

form and color

blindsight

person with cerebral blindness can't see color or form but can sense movement

Anton's syndrome

denial of blindness

achromatopsia

acquired color blindness (left occipital temporal lobe)

visual agnosia

failure to recognize objects through vision (prosopagnosia here as well)