Lecture 7: spatial cognition Flashcards
Spatial scale
- Body space
- Grasping space: what we can touch.
- Instrumental grasping: a bit further.
- Near distant action space: where you can move.
- Far distant action space: where you can move further.
- Visual background: something we know is there.
Small vs. large scale space
Small scale space are your direct surroundings (where did I put my glassed?) and large scale space is everywhere we can go (where will I go next on the map?).
Cognitive domains of small scale space
- Spatial perception.
- Spatial attention.
- Spatial memory.
- Spatial action.
Different cues for perception
- Binocular cues: to identify dept.
- Monocular cues: using our knowledge of the world around us to interpret the size of object.
(Depth vision can be measured with cube test or figure test.)
Spatial relations in the brain
Many brain regions are involved, but a few in particular:
- Hippocampus: information of the mental representation of where we are.
- Visual cortex: spatial perceptual.
- Frontal cortex
- Temporal cortex
- Posterior parietal cortex
Spatial relations
Being able to see the relations between objects around us and the relations between objects and yourself (like picking up a glass). Spatial relations also cause us to be able to follow spatial instructions (go right, go left). There are 2 types of relations between and within objects:
1. Categorial: left, right, straight (left hemisphere).
2. Coordinate: metric properties (5km, 2cm). Comparing the relative distance in our environment.
Dot bar paradigm
Using categorical or coordinate questions to locate a dot. Indicating if a dot is between, above of below other dots.
If the performance goes up –> the left visual field reflects the right hemisphere performance and the left hemisphere is better at coordinate performance.
Brain damage in the left hemisphere
Causes a lot of trouble with categorical changes (the hammer is above the door). Can be measured with realistic search tasks.
Neglect
Inability to perceive stimuli contralateral to our brain damage. It’s an attentional problem, NOT a perceptual or motor problems.
The right hemisphere is often damaged in neglect. Lateralisation causes the other side of the body to be affected. The right hemisphere is dominant for certain functions for both the left and the right side. If only the left side is damaged, the right hemisphere can often take over it’s function.
Testing neglect
- Drawings: like the clock-test or house test.
- Bisecting a line: cutting the line exactly in half.
- Cancellation tasks: cross out the smalls stars.
Treatment of neglect
- There is not really a cure.
- Often a natural recovery.
- Adjustments in daily life need to be made.
- Making the neglected side salient can be helpful.
- Prism adaptation: glasses that show a different perspective.
Ego vs. allocentric
- Egocentric: coding from your own viewpoint. Easily disturbed.
- Allocentric: coding from objects / other points in the room besides yourself. Less easily disturbed.
Constructional apraxia
Action impairment in combining and organising spatial aspects (bringing it together, like all the aspects of a house). The block design test is used to measure this (making a figure out of blocks).
Finding your way in large scale space with 2 strategies
- Orientation: static, for determining your location. Where am I?
- Navigation: dynamic, for reaching your goals. How do I get there?
Orientation
Determining your position in large space by:
1. Landmark-based memory: the association between an object and a landmark (the projector is next to the socket).
2. Boundary-based memory: incidental learning (using the walls of the room as boundaries.
