Chapter 14 - Parietal Lobe Flashcards

1
Q

What’s the general function of the parietal lobes?

A
  • Process and integrate somatosensory and visual information, especially as it pertains to movement control
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What purpose does the intraparietal sulcus have?

A
  • Divides the inferior and superior parietal lobes
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What components make up the inferior parietal lobe?

A
  • Supramarginal gyrus (crescent-shaped)
  • Angular gyrus (posterior to supramarginal gyrus)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What’s another term for the postcentral gyrus?

A
  • S1 (primary somatosensory area)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Which Brodmann’s areas correspond to the superior and inferior parietal lobes?

A
  • Superior - 5 and 7
  • Inferior - 40, and 39
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Which Brodmann’s areas correspond to the anterior zone of the parietal lobes?

A
  • S1 (1-3)
  • 43
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What types of sense is closely associated with the angular gyrus/area PG BA 39)?

A
  • It’s largely visual and contains polymodal regions
  • Larger in the right hemisphere.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What type of inputs does area PG receive?

A
  • Visual, somatosensory, oculomotor (eye movements), cingulate (cognition, emotion), auditory
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What roles does area PG have?

A
  • Role in intermodal mixing
  • Role in spatially-guided behaviour with respect to both visual and tactile information
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What general functions does the dorsolateral prefrontal cortex have (DLPFC)?

A
  • Internally-motivated behaviour
  • Working memory
  • Planning
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Which other brain regions are areas PG/PF highly connected to?

A
  • The DLPFC and the OFC
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

T/F: Posterior parietal areas and dlPFC project to very different areas as a form of parallel processing.

A
  • FALSE
  • They both project to very similar areas including the paralimbic cortex, hippocampus, and various subcortical regions
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Parieto-premotor stream?

A
  • Apart of the dorsal stream anatomy
  • The principle unconscious “how” pathway
  • Affects motor output most directly
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Parieto-prefrontal?

A
  • Apart of dorsal stream anatomy
  • May be related to working memory for visuospatial objects
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Parieto-medial-temporal?

A
  • Apart of dorsal stream anatomy
  • Role in spatial recognition and spatial navigation
  • More perceptual/conscious
  • Projects to the hippocampus and the parahippocampal regions
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Role of anterior zones in parietal lobe function?

A
  • Processes somatic sensations and perceptions
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Role of posterior zones in parietal lobe function?

A
  • Integrates somatic and visual input to control movement
  • Involved in mental imagery (ex. object rotation, arithmetic, reading etc.)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

What’s acalculia?

A
  • Inability to perform mathematical computations
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

What’s the name for Brodmann’s area 40?

A
  • Supramarginal gyrus
20
Q

What would damage to S1 cause?

A
  • Affects thresholds for detecting touch
  • Can create high sensory thresholds (i.e., less sensitive to stimuli)
21
Q

WHat’s afferent paresis?

A
  • Difficulty executing smooth, coordinated movements due to loss of afferent (somatosensory) feedback from the muscles. Don’t have info on what you’re doing
  • Often caused by damage to S1
22
Q

What is astereognosis?

A
  • A somatoperceptual disorders
  • The inability to recognize an object by touch
  • Have normal thresholds, but patient is unable to recognize objects when blindfolded
  • “A loss of body knowledge”
23
Q

What can cause astereognosis?

A
  • Small lesions to S1
24
Q

What’s simultaneous extinction?

A
  • A somatoperceptual disorder- The failure to perceive a sensory stimulus only if that stimulus is presented simultaneously with a second stimulus
25
What can cause simultaneous extinction?
- Damage to secondary somatic cortex (areas PE and PF) in RIGHT hemisphere - ALWAYS RIGHT HEMISPHERE
26
How would you test for extinction in a stroke patient?
- When holding up two objects, patient would have to focus on one object at a time, using their left visual field to identify the object.
27
What's numb touch?
- A type of somatoperceptual disorder - It's the tactile analogue of blindsight - Loss of tactile perception, but are able to locate objects through touch (better than chance selections) - Very rare
28
Asomatognosia?
- Loss of knowledge or sense of one's own body and bodily condition - Most commonly due to right hemisphere lesions
29
What are the different types of asomatognosias?
- Anosognosia - unawareness or denial of illness - Anosodiaphoria - indifference to illness (able to recognize it, but doesn't care) - Autopagnosia - inability to localize and name body parts, caused by left hemisphere damage - Asymbolia for pain - absence of typical reactions to pain, such as reflexive withdrawal from a painful stimulus. Get easily injured. Associated with insular lesions
30
Balint syndrome?
- A host of symptoms of posterior parietal damage - Usually associated with large bilateral lesions, resulting in deficits in visual attention, as well as motor function
31
What three major symptoms make up Balint syndrome?
- Oculomotor apraxia - Optic ataxia (no visually-guided reaching) - Simultagnosia (can't perceive more than one object at a time)
32
What's oculomotor apraxia?
- Paralysis of eye fixation with inability to look voluntarily into the peripheral visual field
33
What's contralateral neglect?
- Another symptom of posterior parietal damage - Neglect of the body or space contralateral to a (usually) right lesion (i.e., ignore the left side of their visual field - It's a deficit of attention, nothing wrong with visual fields
34
When asked to copy a clock drawing, the patient only fills in the right side of the drawing. What might we diagnose this patient with?
- Contralateral neglect
35
What are the stages of contralateral neglect recovery?
- Stage 1: Allesthesia - Stage 2: Simultaneous extinction
36
Allesthesia?
- Responds to stimuli on the neglected side as if they were present on the unlesioned side - Ex. poked on left arm , they may mistake this for being poked on the right arm
37
What brain area is the locus of contralateral neglect?
- Damage to both intraparietal sulcus (divides vs. inferior parietal lobe) and right angular gyrus are necessary
38
What's one theory for why contralateral neglect occurs?
- Left hemisphere orients attention towards right visual space - Right hemisphere orients attention to both visual hemifields - Loss of left parietal function could be compensated for by right hemisphere
39
What's Gerstmann syndrome and its symptoms?
- Caused by damage to left parietal lobe - Symptoms include finger agnosia (can't recognize fingers), agraphia (can't write) , acalculia, right-left confusion
40
What may disturbed language function indicate?
- May be a symptom of left parietal damage
41
What's apraxia and impaired recall?
- Both may indicate damage to left parietal lobe - Apraxia - loss of skilled movement - Impaired recall - Unable to recall a list of numbers properly whether presented orally or visually
42
T/F: Apraxia can be caused by intellectual deterioration.
- FALSE - Apraxia is not caused by weakness, paralysis, intellectual deterioration or poor comprehension
43
Ideomotor apraxia?
- Inability to use and understand non-verbal communication such as gestures or to copy movement sequences - Associated with left posterior parietal lesions (right parietal performs normally)
44
How can you test for ideomotor apraxia?
- Kimura box tests (patient must move through movement series) - Serial arm-movement copying test - Serial facial-movement copying test
45
Constructional apraxia?
- Visuomotor disorder - spatial organization is disturbed - Posterior parietal damage to either hemisphere - Ex. cannot assemble a puzzle, build a tree house, draw a picture
46
Why does damage to the parietal often result in apraxia?
- There's a disruption of the parietofrontal connections that control movement - Posterior parietal cortex receives tactile, visual, and proprioceptive afferent signals and is highly connected to frontal cortex, which commands our movements