Parietal Lobe

posterior zone of parietal lobe

all areas between the post-central gyrus and parieto-occipital sulcus

ventral posterior nucleus

area in the thalamus where somatosensory information is sent via the spine

Balint's syndrome cause

bilateral damage to the parietal lobe

proprioceptive system

body position/movement

somatosensation reception

contralateral

left parietal apraxia

coordination of limb location and distance to reach objects is impaired in both hands

decussation

crossing over

cause of tactical agnosia

damage in posterior region of the parietal lobe

cause of limb apraxia

damage to left parietal cortex, corpus callosum, or frontal lobe

sympathetic limb apraxia

damage to primary motor are which causes complete right arm paralysis and poor left arm movement

hemispheric neglect cause

damage to the parietal lobe

ideational apraxia

difficulty in performing actions (ie using tools properly)

ideomotor apraxia

difficulty in simulating actions (ie demonstrating how to play tennis)

test for constructional apraxia

drawing tasks - drawings are scattered and fragmented, loss of spatial relations, person is overly-energetic and impulsive while drawing

three interactive systems of somatosensation

exteroceptive, proprioceptive, and interoceptive

secondary somatosensory cortex

helping primary somatosensory cortex in initial processing of touch

Balint's syndrome characterisits

inability to perceive the whole visual field, inability to move your hand to an object using vision, difficulty in fixating the eyes

tactical agnosia

inability to recognize touch

schizophrenia relation to parietal

information from the parietal lobe is sent to the temporal lobe which deals with auditory and visual hallucinations

primary somatosensory cortex

initial processing of sense of touch

interoceptive system

internal conditions like temperature and body chemistry

apraxia

loss of action; patient can perform actions but actions are unorganized and inappropriate - affects motor planning

contralateral neglect

lost ability to respond to stimuli in the visual field contralateral to the damaged hemisphere

limb apraxia

movement in wrong limb, incorrect movement in right limb, sequence of movements is incorrect

constructional apraxia

movement is not impaired but the ability to assemble an object or an image is, mental imagery impaired

primary motor cortex

muscle movement

dorsal root ganglion

nodule in the spin that contains nerves that cary sensory info to the brain, starting point for sensory information

not apraxia when

paralysis, primary sensory problems, muscle weakness, other motor disturbances (such as tremors)

cingulate gyrus

part of the limbic system, responsible for regulation of emotion and pain

parieto-occipital sulcus

posterior region of the parietal lobe and separates the parietal and occipital lobes

post-central gyrus

responsible for somatosensation in parietal lobe, part of the anterior zone of parietal

test for spatial relations using mental imagery

rotation test, drawing of body parts/objects in different rotations, identifying which body part belongs to which side of the body

spinothalamic tract function

sends information to the thalamus about temperature, pain, itch, and crude touch

parietal lobe function

sensory info (especially touch), spatial sense and navigation, manipulating objects, knowledge/manipulation of words/letters/numbers, sends info to decision making areas of the brain

central sulcus

separates parietal and frontal lobes and the primary motor cortex and primary somatosensory cortex

later/sylvian fissue

separates parietal and frontal lobes from the temporal lobe

exteroceptive system

skin

cutaneous sensations

skin sensations

direction of information

somatosensory association cortex, primary somatosensory cortex, auditory/visual cortex in temporal lobe, primary motor cortex, frontal lobe

cortical homunculus

spatial map drawn up by Penfield that shows the divisions of the primary motor cortex and somatosensory motor cortex

line bisection test

test for contralateral neglect; patient checks off lines they are aware of

rotation test

test for spatial relations using mental imagery, ability to rotate 2 and 3 dimensional objects in your mind and see them different ways, activates superior parietal cortex

foam board test

test for tactical agnosia, patient is blindfolded and needs to be able to place objects such as shapes in the correct location on the board, then asked to draw the board

parieto-temporal juncture damage

theory of mind impaired, patients cannot complete images to get the full thing

damage to anterior region of parietal lobe

touch and finger manipulation

somatosensory system functions

touch, temperature, body position, pain

callosal limb apraxia

transfer of info to the right hemi is blocked, so left side movement is affected

two point discrimination test

used to show if there's damage to the parietal lobe - patient is blindfolded and needs to be able to tell if two points of an object touched them or just one

cause of constructional apraxia

usually damage to the right hemisphere

cause of contralateral neglect

usually right hemi, image is processed not seen (patients can pick a world that related to the image flashed even if they ca't see the image)

monkey neglect experiment

we process information in our visual field even if we don't look directly at it, neurons in posterior parietal fire

extinction in neglect

when you can see any stimulus when it is presented by itself but when paired with another similar stimulus and shown together, only one is perceived and one is extinguished

normal people neglect

yes; right side