Presentation on theme: "Lecture 8: Depression: Why you learn better when you are sad C83MLP Mechanisms of Learning and Psychopathology Dr. Mark Haselgrove."— Presentation transcript:
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 & Abramsons (1979) challenge (3) Replications of Depressive realism:Successes Failures (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 fear 0.0 = 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: ΔP = = 0.5 ΔP = = 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 between Their 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 Depressed and Non-depressed groups Discussion point: Do these data support or challenge Seligmans 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 groups ΔP 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 Seligmans 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 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 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 $5.00 Each trial with no light = -$ 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 students Naturally 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-esteem Non 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 behaviour Underestimate their control over undesired behaviour The depressed, dont. 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 the control they have over their behaviour, should see illusion of control when 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) Varied: ITI - Long (15 s), or Short (3 s) Depression - Depressed, or Not depressed Outcome 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 errors If Context is poorly processed:A-Y errors < B-X errors 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)