Lecture 8: Depression: Why you learn better when you are sad C83MLP Mechanisms of Learning and...

Lecture 8:

Depression: Why you learn better when you are sad

C83MLP Mechanisms of Learning and Psychopathology

Dr. Mark Haselgrove

Content of Lecture

(2) Helplessness theory: Alloy & Abramson’s (1979) challenge

(3) Replications of Depressive realism: SuccessesFailures

(1) What is contingency and how do we measure it?

(5) Theories of Depressive realism

(4) Depression ↔ Realism?

- Motivation theory

- Context processing

What is contingency?

(1) Rescorla (1968)

Suppression ratio:

R(Tone)

R(Tone + No Tone)

0.5 = no fear0.0 = lots of fear

What is contingency and how do you measure it?

(1) Allan (1980)

Defined contingency in terms of responses and outcomes (Instrumental learning)

ΔP = P(O|R) – P(O|~R)

a c a + b c + d=

Discussion point:Work out the ΔP for

these:

20 010 10

15 515 5

ΔP = 1 - 0.5 = 0.5 ΔP = 0.75 - 0.75 = 0

Helplessness theory

Seligman (1975)

Depressed people: Generalized expectancies of independence between their responses and outcomes

Believe they are powerless to control the world

Alloy & Abramson (1979)

Depressed people should therefore underestimate the contingency betweenTheir responses and environmental outcomes

Helplessness theory

Alloy & Abramson (1979) Cont…

- 40 discrete trials (each lasting 3 s) in which ss could press a button (R) or not (~R). Green light was then illuminated (O) or not (~O)

- At the end of 40 trials, ss rated the control they had over the light: (0= no control, 100= complete control)

- Experiment 1: 96 undergrads, divided into depressed & non-depressed groups Beck Depression Inventory (Beck, 1967)

No difference between Depressedand Non-depressed groups

Discussion point:Do these data support

or challenge Seligman’s theory?

Helplessness theory

Alloy & Abramson (1979) Still Cont…

- Non-depressed people should have a generalized expectation of control- Should interfere with their judgements of non-contingencies (ΔP = 0)

- Experiment 2: 64 undergrads, divided into depressed & non-depressed groupsΔP set to zero, P(O) varied:

0.25 (low outcome density) 0.75 (high outcome density)

- Non-depressed = Illusion of control- Depressed = Depressive realism

Do these data still challenge Seligman’s

theory?

Replications: (1) Successes

Lennox et al. (1990)

- Replicated Alloy & Abramson, Exp 1: Looked at different patient groups:- Major depressive disorder- Schizophrenia with or without depression- Non-psychiatric patients

- Two levels of ΔP (0.25, 0.75)- Again, no difference in ratings of control between groups

Vasquez (1987)

- ΔP and P(O) confounded by A&A and Lennox et al:- As one goes up, the other goes down:

- Vasquez (Exp1) corrected for this. Held P(O) constant and varied only ΔP

- Replicated A&A Exp 1 result

Replications: (1) Successes

Vasquez (1987) Cont…

- Replicated A&A Exp 2- 16 Spanish undergrads, 8 depressed, 8 non-depressed (determined by BDI)

Low P(O)High P(O)

- Extends generality of Depressive-realism effect

- See also Presson & Benassi (2003) for another recent replication

Replications: (2) Failures

Bryson et al. (1984)

- Failure to Replicate A&A Exp 2- 64 Male and female undergrads, - Depressed and non-depressed (again determined by BDI)

Low P(O) High P(O)

Neither Depressed nor non-depressed individuals showed an illusion of control

Kapci & Cramer (1999) both mood groups showed an illusion of control: ratings increased for both groups with P(O)

Depression ↔ Realism?

Alloy & Abramson (1979) – Experiment 3

- Varied outcome valence rather than probability

- Thus an outcome was made either desirable or undesirable (rather than frequent or infrequent)

- ΔP =0, P(O) = 0.5 Win Condition = SS Starts with $0 Each trial with a light = +$0.25

Lose Condition = Ss Start with $5.00 Each trial with no light = -$0.25

- For the lose condition….Ratings of control low for both moods- For the win condition…..Nondepressed > Depressed

An Outcome Valence effect

Depression ↔ Realism?

Alloy, Abramson & Viscusi (1981)

- Used the Outcome Valence effect

- Induced elated and depressed mood states in (respectively): Naturally depressed female studentsNaturally nondepressed female students

(1) Depressed state induced by ss reading negative self-referent statements:“I have had too many bad things happen in my life”“I want to go to bed and never wake up”

(2) Elated state induced by ss reading positive self-referent statements:“God, I feel great!”“Things will be better and better today”

(3) Control ss (depressed and nondepressed) read neutral statements:“Utah is the Beehive State”

Depression ↔ Realism?

Alloy, Abramson & Viscusi (1981) Cont…

No/ Neutral induction: Nondepressed > Depressed

- Depressives made “happy” showed illusion of control- Nondepressives made “sad” showed realism

Depression → realism

Discussion point:Depression → Realism or

Realism → Depression

Naturally depressed students given elation induction gave higher ratings than non-depressed students given depression induction

Theories of Depressive Realism

Alloy & Abramson (1979)

Motivational Theory…

Depressed People → Low self-esteemNon Depressed People → High(er) self-esteem

Non-depressed people engage in behaviours to enhance their self esteem

In particular, distort reality, in an optimistic way

Thus nondepressed: Overestimate their control over desired behaviourUnderestimate their control over undesired behaviour

The depressed, don’t. They have a specific motivation to preserve self esteem

Theories of Depressive Realism

Alloy & Abramson (1979)

Why is depressive realism restricted to high levels of P(O)?

If non-depressives overestimate thecontrol they have over their behaviour,should see illusion of controlwhen P(O) = 0.25

Theories of Depressive Realism

Msetfi, Murphy, Simpson & Kornbrot (2005)

The Inter-trial Interval (ITI) hypothesis

3 s

14 s

A&A Experiment structure:

Alan & Jenkins (1980): Removing the ITI, resulted in no outcome density bias

Is there something special about the ITI….?

Theories of Depressive Realism

Msetfi, Murphy, Simpson & Kornbrot (2005)

Theories of Depressive Realism

Msetfi, Murphy, Simpson & Kornbrot (2005)

Varied: ITI - Long (15 s), or Short (3 s)Depression - Depressed, or Not depressedOutcome density - High [P(O) = 0.75, or Low [P(O) = 0.15)

Theories of Depressive Realism

Msetfi, Murphy, Simpson & Kornbrot (2005)

What is it about depression and the ITI?

Morrow & Nolen- Hoeksema (1990) – Depressed people spend time ruminating about their feelings and symptoms

Perhaps attention is diverted during ITI in depressed people

- Do not use information provided by the ITI, or (background context) to evaluate the relationship between noR and noO

Theories of Depressive Realism

Msetfi, Murphy, Kornbrot & Simpson (2009)

Do depressed people have a deficit in processing contextual information?

AX continuous performance task:- Letters presented sequentially on a computer screen- Have to respond when they see “X” (Target) – only after “A” (Context)

Look at errors on the distractor trials: A-Y and B-X

If Context is well processed: A-Y errors > B-X errorsIf Context is poorly processed: A-Y errors < B-X errors

0

0.05

0.1

0.15

0.2

AY BX

Error type

Me

an

pro

po

rtio

n e

rro

r

Depressed

Nondepressed

Depressed people have a deficit in context processing

OK, so you can explain data for ΔP = 0, what about ΔP ≠ 0

Theories of Depressive Realism

OK, so you can explain data for ΔP = 0, what about ΔP ≠ 0

Theories of Depressive Realism

Is this true? Read:Msetfi, Murphy & Simpson (2007)

Further reading…

Further reading…