Lecture 6 - Spatial cognition and memory

Question 1

O’Keefe and Nadel (1978) conceptualised the hippocampus as a cognitive map - what does this mean and how is it different to response learning?

Answer 1

1) The hippocampus evolved for making storing & using maps of the external world (navigation). It models the external world.
2) The hippocampus is especially crucial for map-based navigation, not for route learning aka response learning (this is purely based on associations, not a conceptual map)

Question 2

According to O’Keefe and Nadel (1978), does map-making occur automatically?

Answer 2

Yes

Question 3

The hippocampus notices novelty. What does novelty drive?

Answer 3

Exploration; the purpose of exploration is to build and update maps

Question 4

What type of memory builds on the system of the hippocampus as a cognitive map?

Answer 4

Episodic

Question 5

What does map based navigation involve?

Answer 5

Creating new routes through familiar environment e.g. if normal route is closed

Question 6

Is the hippocampus very different across mammals?

Answer 6

No - it is very similar

Question 7

Is the hippocampus close to the medial temporal lobe?

Answer 7

Yes

Question 8

What do the EC and DG do in relation to the hippocampus and cortex?

Answer 8

Serve as gateways separating the cortex from the hippocampus - like a relay station

Question 9

What is the difference between response learning and place learning?

Answer 9

Response learning - Self-based direction - always turn left
Place learning - Place-based direction - always turn towards the direction of this landmark (requires cognitive map)

Question 10

How does the case of HM support the role of the hippocampus in spatial memory?

Answer 10

HM had hippocampus removed
HM could not “form an instantaneous cognitive map”
Relied on response learning

Question 11

What is the spatial navigation double dissociation?

Answer 11

Place learning = hippocampus
Response learning = caudate nucleus

Question 12

Does the hippocampal formation represent allocentric or egocentric space?

Answer 12

• Allocentric or environment-centred, large scale space - necessary for cognitive map - this can be used in novel situations whereas egocentric representations cannot
  
  • Functions: navigation, long-term memory for scenes, spatial contexts, binds items-in-contexts

Not egocentric - this is more typical of response learning

Question 13

How were place cells discovered?

Answer 13

O’Keefe and Dostrovsky (1971) and O’Keefe (1976)

Recording individual cells at a time

Animal moves freely, then they drop rice which the animal moves to and investigates
Found individual cells that only respond when animal is in a certain place in the environment

Question 14

What do place cells do?

Answer 14

Each cell responds similarly to its neighbour
All places in environment that animal has learnt are represented in hippocampus
Place cells signal a specific location from a specific context
If put animal in different environment, same cell starts doing something different - adaptability

Place cells firing together signal a specific location in a specific spatial context

Question 15

In addition to place cells, what are 4 other types of cells that aid spatial navigation?

Answer 15

Speed cell
Head direction cell
Boundary vector cell
Grid cell
- Could be path integration system - how far into the environment you might have moved e.g. still works when the lights go out - in what direction did you move and how far - identify your own specific position in environment

Question 16

What happens to performance on Morris Water Maze when rats have hippocampal lesions?

Answer 16

Impaired in finding platform, paths are inaccurate - because allocentric coding is needed
Longer, inaccurate routes

Question 17

Maguire et al. (1998) studied ppts performance on navigating through a virtual town, while measuring activity with a PET scan. How did people with hippocampal lesions, cortical lesions, and controls perform?

Answer 17

Cortical lesioned and control ppts took an accurate direct path
Hippocampal lesioned ppts took an inaccurate circuitous path

Question 18

Maguire et al. (1998) studied ppts performance on navigating through a virtual town, while measuring activity with a PET scan.
What did the PET scan show correlated to more bloodflow to the hippocampus?
What other area was involved?

Answer 18

More bloodflow to hip = higher accuracy on task

Navigational accuracy positively correlated with:
Hippocampal activity (r = 0.56)
& with Inferior Parietal activity (r = 0.43)

Question 19

What was a methodological issue with Maguire (1998)?

Answer 19

Lots of within subject variation

Question 20

What was the method in Hartley et al. (2003) study of route following and wayfinding?

Answer 20

Town 1 - wayfinding
Training was free exploration for 15 minutes
Town 2 - route following
Training was to follow a fixed route for 15 minutes
There was a non-memory control to follow a visible trial
Brain activity recorded

Question 21

In Hartley et al. (2003), what were brain activation differences between route followers and wayfinders?

Answer 21

Better navigators use their hippocampus more for way-finding navigation
Better navigators use their caudate less for way-finding navigation

Question 22

What kind of brain wave comes from electrode recordings in the hippocampus?

Answer 22

Theta oscillation (around 8hz)

This has been found to occur:
during rat exploration of environment (A)
during human virtual exploration of environment (B)

Question 23

Are cells more likely to fire at the peak of oscillation?

Answer 23

Yes

Question 24

Cornwell et al. (2008) studied hippocampal theta oscillation when people navigated a virtual morris water maze. What did MEG activity show?

Answer 24

Hippocampal Theta power increases during water maze performance (particularly at beginning of trial)

Therefore,
Hippocampal Theta power at beginning of trial strongly predicts navigational accuracy

Question 25

Which part of the hippocampus is localised to anxiety and which part is localised to spatial memory?

Answer 25

Anterior hippocampus = anxiety Posterior hippocampus = spatial memory

Question 26

What were results of a double dissociation of spatial cognition and anxiety with regards to hippocampal theta? (Cornwell et al., 2012)

Answer 26

Better navigators had stronger theta in posterior hippocampus More anxious people had stronger theta in anterior hippocampus (this was lower frequency)

Question 27

Schinazi et al. (2013) had ppts navigate a university campus, learning two routes. In subsequent sessions, ppts learnt connecting routes between them. What gender differences and hippocampal size differences were found?

Answer 27

Overall - males better than females, however not significant hippocampus differences between them Better map learners had larger right hippocampus (particularly posterior hippocampus)

Question 28

Do better navigators have larger hippocampi? Is this an increase of grey or white matter volume?

Answer 28

Yes Grey matter volume

Question 29

What did Maguire discover about the hippocampi of London taxi drivers?

Answer 29

1) Main result: Larger posterior hippocampal volume in taxi drivers (2006: > bus drivers) 2) Smaller anterior hippocampal volume in taxi drivers (not shown here) 3) Both studies: The longer time spent as taxi driver, the larger the posterior hippocampus

Question 30

What was an issue with Maguire's original taxi driver study?

Answer 30

Cause and effect: Do people who have largest hippocampus to begin with seek out taxi driving as a career more because they are good at it, or does hippocampus become larger with experience as a taxi driver?

Question 31

How did Woolet and Maguire (2011) investigate the effect of 'the Knowledge' on structural brain changes?

Answer 31

Brain imaging at one time and then three years later Recorded who was qualified, who failed to qualify, and also controls

Question 32

What brain differences were observed between qualified and non-qualified trainees in Woolet and Maguire (2011)?

Answer 32

Grey matter volume increase in right posterior hippocampus for those who passed 'the Knowledge' No change for non-qualified trainees (people who failed the exam)

Question 33

Malanchini et al. studied genetic factors for navigation using 6 spatial tasks, 10 object spatial tasks, and various non-spatial cognitive tasks. What are examples of these tasks, and what was the distribution of scores on the spatial ability tasks?

Answer 33

e.g. map reading and perspective taking a) Largely asymmetric (long tail at weak end). Only ‘Navigation directions’ shows an even distribution. b) Some bimodality in perspective taking & map reading. A few people are very very good

Question 34

Malanchini et al. - what was the heritability of a 'common navigation factor' across all 18 tasks?

Answer 34

64%

Question 35

Malanchini et al. - what was the heritability of an overall 'spatial ability factor'?

Answer 35

84%

Question 36

Malanchini et al. - how much heritability of the overall 'spatial ability factor' was accounted for by g, and how much was accounted for by a g-independent spatial ability factor?

Answer 36

55% of this 84% was accounted for by g, and 45% by a g-independent spatial ability factor.

Question 37

Malanchini et al. - factor analysis revealed what three factors and what overall factor?

Answer 37

Overall factor = spatial ability 3 factors = object manipulation, visualisation, navigation

Question 38

Is heritability of spatial ability high?

Answer 38

Yes

Question 39

What are the two broad components of heritability of spatial ability?

Answer 39

a general cognitive ability factor (g) a separate factor, (spatial g) Remember: each factor depends upon many, many genes.