Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
16 Cards in this Set
- Front
- Back
|
Describe the profile of Patient DF (Milner et al., 1991) in terms of symptoms |
Spared reaching and grasping to objects varying in size and orientation despite being at chance in making perceptual judgements based on the same information |
|
|
Describe the profile of Patient DF (Milner et al., 1991) in terms of neurological damage |
bilateral lesions at the back of the the brain in the overlap areas of the lateral occipital complex |
|
|
What do Patient DF's symptoms indicate about dissociations within vision? |
vision for action and vision for recognition may be dissociated |
|
|
What effects were seen in Patient DF's performance when a delay was introduced in between seeing the object and reaching for it/indicating its size?
What dissociation does this pattern of behaviour indicate? |
DF failed to show size scaling in the delayed action tasks when asked to reach for the shapes
Size scaling also remained impaired in the perception indication conditions
This suggests that DF can only use visual guidance of action 'on line' and as such that visual information used for on-line action differs from that used for conscious judgements |
|
|
Which areas of the brain are predominantly implicated in pattern and space recognition? |
pattern - temporal lobe space - parietal lobe |
|
|
Why do ventral area lesions not necessarily disrupt online processing of visual information? |
The dorsal 'where' pathway supports online action |
|
|
What general deficit is seen when the ventral 'what' pathway if lesioned? |
Agnosias |
|
|
What pattern of activity would you expect to see in subtraction fMRI images of activity when a person is reaching/grasping vs pointing to an object |
dorsal pathway implicated in pointing ventral pathway implicated in grasping |
|
|
What particular impairment causes deficits in reaching/grasping but not in indicating size/scale? |
Optic ataxia |
|
|
How can optic ataxic's performance in grasping tasks be reverted to control-level? |
Introduce a delay between observation of the object and the reaching prompt. |
|
|
What types of objects can optic ataxics scale to size to reach for? |
Salient items - bowling balls, etc. Familiar objects - a lipstick from their purse, etc.
Dijkerman, Milner and Carey, 1998 Jeannerod et al., 1994 |
|
|
What are utilisation behaviours? |
Behaviour that is strongly and automatically driven by the presence of stimuli - not driven by tasks or normal social constraints. |
|
|
Who conducted an experiment involving a patient with utilisation behaviour? What was observed? |
Riddoch et al., 1998
1. patient is told , if the cup is on the left pick it up with your left hand, if its on the right, pick it up with your right hand. 2. cup is presented on the left with the handle on the right hand side, the patient invariably uses their right hand. |
|
|
Where are affordance effects neurally based? |
In the ventral visual pathway |
|
|
What are affordances? |
Effects of positioning objects for action in attention tasks |
|
|
Which pathways are damaged in a) agnosias b) optic ataxia |
a) ventral 'what' pathway b) dorsal 'where' pathway |
