What are the kinds of space?
- Spatial behaviour (guides us through space)
- Topographic memory (ability to move through space from one place to the next)
- Cognitive maps (mental representations we have of space)
- Body space (surface of the body)
- Grasping space (area around the body)
- Distal space (space the body move in and out of)
- Time space (past and future)
What role does the frontal lobe play in spatial behaviour?
- Important for spatial discriminations
- No vision to navigate environments if frontal lobe is removed
- Guiding responses on basis of stored information in absence of external cues
- Memory for location of objects
What role does the temporal cortex play in spatial behaviour?
- The hippocampus serves as a cognitive map (spatial mapping - damage results in deficits in piloting and dead reckoning)
- Hippocampus is involved in food-caching behaviour in animals (animals use distal spatial cues to find their caches, larger hippocampus in animals that cache)
- Dead reckoning (damage to hippocampus results in disruption of dead reckoning in rats - normally rats can use room cues and self-movement for guidance, can return home when all auditory and olfactory cues are removed)
- Food-storing experience - if prevented, hippocampus size lags behind
- Changes in neurogenesis (largest changes when birds are storing food)
What is the role of the parietal cortex in spatial behaviour?
- Eight visuospatial disorders result from parietal lobe damage (Balint’s syndrome - impairments in gaze direction and reaching movements)
- Spatial localization (dot location task - patients with right hemisphere lesions were impaired)
- Depth perception (dot stereograms, normal subjects and left hemisphere damage perceived normally, not right hemisphere damage)
- Parietal cortex (provides coordinate system of visual space and to locate objects in this space)
- In absence of this system, patient can still see object but cannot direct gaze or hand movements toward it
What are the differences between position, cue, and place responses?
- Position response: Navigational behaviour in which an animal uses its previous movements as a cue - that is, movements previously made to arrive at the same location
- Cue response: Navigational behaviour in which an animal locomotes to a position on the basis of its location relative to a single cue
- Place response: Navigational behaviour in which an animal locomotes to a position on the basis of its location relative to two or more cues
What are the principal deficits in spatial orientation in people?
- Egocentric disorientation
- Heading disorientation
- Landmark agnosia
- Anterograde disorientation
- Spatial learning
What is egocentric disorientation?
- Posterior parietal lobe damage
- Deficits in perceiving the relative location of objects
What is heading disorientation?
- Posterior cingulate damage
- Unable to set a course; no “sense of direction”
What is landmark agnosia?
- Lingual gyrus damage
- Unable to use prominent environmental features for orientation
What is anterograde disorientation?
- Parahippocampal gyrus lesions
- Unable to learn new representations
- Can navigate
What is a deficit in spatial learning characterized by?
- Hippocampal damage
- Deficits in spatial learning may be due to the hippocampus’ role in spatial navigation or in memory
- Right hippocampus has a special role in complex spatial abilities
What are the different types of topographic disorientation?
- Topographic disorientation
- Topographic agnosia
- Topographic amnesia
- Retrograde spatial amnesia
- Anterograde spatial amnesia
What is topographic disorientation?
-Difficulty finding your way around
What is topographic agnosia?
- Inability to identify individual landmarks
- Can recognize a building as a church, for example, but will not know it it “their” church
What is topographic amnesia?
-Inability to remember relationship between landmarks
What is retrograde spatial amnesia?
-Loss of ability to navigate in environments that were familiar before injury
What is anterograde spatial amnesia?
-Loss of ability to navigate in novel environments
What is unique about London taxi drivers and their spatial abilities?
- They have a larger hippocampus
- Found that spatial tasks activated the: occipitotemporal area, medial parietal cortex, posterior cingulate cortex, parahippocampal gyrus, and right hippocampus
- Right posterior hippocampus increased in size as a function of how long person was a taxi driver (shrunk interior of hippocampus, which led to poor spatial ability on new spatial tasks)
What are the different types of spatial behaviour?
- Route following
- Piloting
- Dead reckoning
What is route following?
-Follow a road or path to a specific object/location
What is piloting?
- Ability to find a place that is not directly marked by a route/cue
- E.g., Morris water maze - use spatial cues in environment to find platform
What is dead reckoning?
- Depends on cues generated from ones own movement
- An early form of navigation that uses direction, speed, and travel time
- Non-human animals (self-movement cues for dead reckoning - sensory flow, movement commands)
What do animals direct their spatial abilities toward? What information do they use to guide their spatial behaviour?
- Animals use spatial ability to forage for food, store food, locate objects, return to a home base, and migrate
- They use visual, auditory, and olfactory information, sightings on the stars, geomagnetic fields, and gravitational force to guide their spatial behaviour
What are place cells?
- Navigate in relation to environment
- Discharge when an animal is in a certain place in an environment (fire in particular places, when animal is changing direction)
- Maintain activity in the dark
- When environment is rotated, cells discharge according to the new pattern
- Prefer visual cues - fire in response to a single one, stop responding when that cue is removed
- Fire in response to objects
- Sometimes active in only one environment
- Activity is linked to ability to move
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The Temporal Lobe32
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Cerebral Asymmetry34
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Language30
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Emotion15
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Neocortical Function6
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The Occipital Lobe19
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The Parietal Lobes19
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Organization of the Motor System19
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Spatial Behaviour29
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Learning and Memory46
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Brain Development and Plasticity26
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Learning Disabilities19
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Plasticity, Recovery, and Rehabilitation of the Adult Brain25
