Parietal Lobe

Question 1

What is the primary area of the parietal lobe and what does it do

Answer 1

Primary somatosensory cortex, i.e. the post-central gyrus, receives sensory information from the body

Question 2

How is the Primary somatosensory cortex organised

Answer 2

Topographically organised – i.e. homunculus

Question 3

What is the primary sensory region of the parietal lobe known as

Answer 3

post-central gyrus or somatosensory strip

Question 4

Where is the Sensory homunculus mapped

Answer 4

somatosensory strip

Question 5

what does the post-central gyrus do

Answer 5

receives sensory information about a particular region of the body, from the contralateral side of the body

Question 6

moving out laterally along the cortex, the homunculus represents parts that are…

Answer 6

closer and closer to the head

Question 7

what deficits/impairments does Lesion/disconnection of the primary, somatosensory strip result in

Answer 7

Leads to a primary sensory deficit.
Tactile discrimination impaired
Tactile thresholds reduced,
Reduced ability to detect object characteristics such as an edge or a curve

Question 8

What is the secondary area of the parietal lobe

Answer 8

Unimodal Association area

Question 9

What does the Unimodal Association of the parietal lobe area do

Answer 9

receives inputs from the primary somatosensory cortex and integrates these inputs so that the tactile stimulus can then be perceived.

Question 10

What does Lesion/disconnection of unimodal association of the parietal lobe area result in

Answer 10

tactile perceptual deficits which may include:

  - An inability to judge the orientation of a tactile stimulus
  - Tactile agnosia - an inability to recognise an object by touch.      
  - This is an inability to perceive the object, not a primary inability to sense the object

Question 11

What is the tertiary area of the parietal lobe

Answer 11

Multi-modal integration Area

Question 12

What are the three main areas of the parietal lobe

Answer 12

1. post-central gyrus or somatosensory strip
2. Unimodal Association area
3. Multi-modal integration Area

Question 13

The Tertiary region of the parietal lobe is at the crossroads of what other areas

Answer 13

temporo-parieto-occipital crossroads

Question 14

What does the Multi-modal integration Area of the parietal lobe do

Answer 14

multi-modal integration of sensory information including tactile, somatosensory, visual, auditory and vestibular information

Question 15

Lesions that disrupt Multi-modal integration in the parietal lobe principally seem to effect what

Answer 15

understanding of spatial relations

Question 16

much of the function of the parietal lobes involves understanding what

Answer 16

spatial properties of the world in which we live, including the spatial properties of our own body in that world

Question 17

parietal lobes are essential in constructing what

Answer 17

mental maps of the world

Question 18

Disorders of spatial attention result in what 7 impairments

Answer 18

(i) Disorders in the judgement of the location or orientation of stimuli, both with respect to each other and to the person
(ii) Impaired memory of location
(iii) Topographical disorientation and loss of topographical memory
(iv) Route finding difficulties – due to a difficulty in being able to synthesise and integrate spatial information, such as on maps
(v) Constructional apraxia
(vi) Unilateral spatial neglect
(vii) Disorders of body schema

Question 19

What is visuospatial agnosia

Answer 19

difficulty in perceiving the spatial relationships between several objects in one’s visual field

Question 20

What is a test of visuospatial agnosia

Answer 20

Benton Visual Retention Test

Question 21

how does Impaired memory for location affect a persons understanding of objects

Answer 21

The patient can recall what the objects were, but can not recall where they were located

Question 22

What is a test of Impaired memory for location

Answer 22

the REY Complex figure with and without a memory loading

Question 23

When doing the REY Complex figure what is the difference between Frontal lobe patients and Parietal lobe patients

Answer 23

Parietal lobe patients can’t understand the spatial organization of the figure.
* Parietal lobe patients improve performance when guided with spatial information.

• Frontal lobe patients show disturbances in the plan to approach the copying of the figure.
• Frontal lobe patients improve performance if provided with a plan.

Question 24

What is Topographical Disorientation

Answer 24

An inability to utilise landmark objects to orient and to localise everything within a spatial representation

Question 25

Topographical Disorientation results from an inability to do what 2things?

Answer 25

1. recall the spatial arrangement of familiar surroundings

2. recall and describe well-known geographical relationships with which the patient was formerly familiar.

Question 26

What is suspected to be the fundamental problem behind Topographical Disorientation

Answer 26

seem to involve problems in the recall of visual images from long term memory

Question 27

What are the 4 basic disorders that may explain Topographical Disorientation

Answer 27

1. perceptual disorders (of the location and relative position of objects).
2. failure of recognition of environmental feature
3. topographical amnesia. i.e a specific inability to remember landmarks within the spatial representation, as opposed to the broader inability to utilise objects as landmarks in the spatial represenation.
4. unilateral spatial neglect (i.e. impaired attentional processing.

Question 28

What is a test of Route Finding Difficulties

Answer 28

Semmes Locomotor Map

Money’s Road Map

Question 29

What is Constructional Apraxia

Answer 29

inability to construct/join/assemble parts of an object in order to form a unitary structure.

Question 30

Where does Constructional Apraxia occur

Answer 30

patients with lesions at the overlapping parietal, temporal and occipital junction.

Question 31

Constructional apraxia arising from parietal lobe lesions occurs mostly in which hemisphere

Answer 31

right hemisphere lesions

Question 32

What are 2 tests of Tests for Constructional Apraxia

Answer 32

WAIS Block design

Rey Complex Figure

Question 33

What is Contralateral neglect

Answer 33

inability to attend, perceive or process information from one side of your visual space.
The hemi-space that is neglected is contralateral to the side of the parietal lobe that is lesioned, hence it is usually referred to as contralateral neglect.

Question 34

Where does Contralateral neglect occur and what does it effect

Answer 34

Contralateral neglect nearly always involves a right parietal lobe lesion, causing neglect to the left hemi-space

Question 35

disorders of body schema and lack of awareness of body parts can occur as a result of damage to which lobe

Answer 35

Parietal lobe damage

Question 36

What is a test of disorders of body schema and lack of awareness of body parts

Answer 36

simply involve asking patients to identify / point to parts of their own bodies or on a diagram.

Question 37

How does the parietal lobe effect movement

Answer 37

parietal lobes to help us control our movements, if we don’t know anything about our position in our environment, can’t track our movements and understand them then it is hard to move with any confidence e.g., driving a car

Question 38

Which other brain areas is the Multi-modal integration Area of the parietal lobe attached to and what is the result

Answer 38

Motor Cortex - information about our body position is crucial for our movements
Temporal Lobe - reading difficulties - spatial recognition of letters

Question 39

What are two elements of spatial understanding

Answer 39

1. determine the relationship between objects in extra-personal space
2. understand where our body is, in relation to extra-personal space.

Question 40

Topographical Disorientation is often seen is patients with what disease

Answer 40

Alzheimers

Question 41

Disorders of location and orientation involve 2 things

Answer 41

1. difficulty localising an object in a visual field

2. perceiving the spatial relationships between several objects in one’s visual field.

Question 42

How can we differentiate between constructional apraxia in frontal and parietal patients

Answer 42

Frontal lesion - loss of planning and regulating sequential behaviour;
Parietal lesion - loss of spatial understanding of the elements