1. Systematic biases in perception and memory – harnassing for good
Glyn Humphreys

2. Everyday slips of action
Who has ever……?
Picked up the wrong thing or
poured into the wrong
container when doing two things at once
Taken the more familiar route when you meant to be going the other way
Everyday slips of action

3. Utilisation behaviour (Lhermitte, 1983)

4. Presentation title, edit in header and footer (view menu)
June 23, 2018
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5. How can we understand these problems?

6. There are many cues that we face throughout everyday
life, and we have:
A system that responds to the cues in an
automatic and fast-acting way
(b) A system that is more under conscious control
but involves mental effort and is slower in action
Kahneman (2011) Thinking, fast and slow:
System 1 (fast automatic)
System 2 (slow, effortful)

7. Kahneman argues that the operations of ‘system 1’ pervade
many aspects of thinking
A bat and ball costs £1.10.
The bat costs £1 more than the ball.
How much does the ball cost?
Especially when under time pressure, 10p comes to mind
BUT if the ball is 10p and the bat is £1 more – then how much
would the bat cost ?
£1.10, making it all £1.20
Correct answer: £5p
June 23, 2018

8. Proposal – the fast system jumps to the answer based
on the availability of ‘10’ and the rapid segmentation of
£1.10 into £1 [bat] and 10p [ball]
Fast system is ‘intuitive’ but can come to the wrong conclusion
Fast system works on association and ‘priming’
Left half of the room think about lunch
Right half of the room think about having a shower
Complete the word SO_P as fast as you can

9. We can be primed unconsiously - do people put money into
an honesty box when paying for coffee (Bateson et al., 2006)?
June 23, 2018

10. June 23, 2018

11. These biases also vary according to whether the
stimuli are related to ourselves or not
There is considerable work showing that humans show a bias towards information related to themselves
Memory (Conway et al., 1996)
Trait evaluation (Klein et al., 1989)
Face recognition (Keenan et al., 1999)

14. Just as in Kahneman’s examples, these biases can be harmful+

15. These biases pervade even very simple tasks
Draw a triangle and label each corner : stranger, you, best friend
Draw a line: position your best friend, you, stranger labels along the line
Now write which name you put first on the page
You to the left and first

16. You
Friend
Stranger

17. You

18. Stranger

19. You

20. Friend

21. Stranger

22. Stranger

23. Is there a difference in matching the different shape-label combinations (Sui, He & Humphreys, 2012, JEP:HPP)?

25. Massive self-advantage
Gained within 15 learning trials

26. Trait-like measures -Reliable across test sessions

27. Effect on perception: change the contrast of the shape
Effects of social
association modulates
effects of stimulus contrast
on perceptual sensitivity
Evidence for a perceptual
locus

28. Involvement of a specific brain circuit
Participants performed the self-association match task in the scanner
How do brain states change to generate the effect (Sui, Rotshtein & Humphreys, 2013, PNAS)?

29. vmPFC classically associated
with self processing
LpSTS linked to the ventral
attentional network
Linking of self to socially
salient signal

30. Dynamic causal model:
Stronger intrinsic connectivity
from vmPFC  LpSTS, the
more efficient performance for
matching self trials

31. Activity in the classic
dorsal attention control
network
Self bias not
modulated by the ‘slow’
attention system

32. Self-matching affected by a neural circuit connecting self representations (vmPFC)  attentional responses to sensory signals (LpSTS)
Strength of connections within this circuit determine the efficiency of behaviour to self-associated stimuli

33. Can these effects be usefully harnessed – e. g
Can these effects be usefully harnessed – e.g., to improve performance?
Example – using self reference in memory

34. GA – patient who suffered herpes simplex encephalitis – severe amnesia
We assessed if his amnesia could be reduced
by having him make personal associations with stimuli –
objects assigned as belonging to him or sister

35. 25% improvement from linking to the self

36. GA asked to evaluate if he liked the object, or if his sister
Improvement certainly in source memory after relating to the
self

37. Conclusions
Human cognition is systematically biased in various ways – fast vs. slow decisions
Self-biases are pervasive, consistent and fast
Such biases can be used though to improve cognition and may provide a useful scaffold for learning
Good teachers make learning relevant to the individual
June 23, 2018

38. T h e E n d