Presentation on theme: "Super control Out of control In control Healthy, happy, effective, wellbeing Delusions of control. Obsessive control Helplessness, hopelessness, suicidal."— Presentation transcript:
Super control Out of control In control Healthy, happy, effective, wellbeing Delusions of control. Obsessive control Helplessness, hopelessness, suicidal thoughts
Background Feeling in control involves learning about action-outcome causal relationships How we do it: As cause cannot be observed, it must be inferred (Hume): space, time, contingency Two broad theoretical accounts of the causal process : Associative models & inferential accounts When it goes ‘wrong’: Different theory: e.g., cognitive accounts of depression invoking higher level constructs Self esteem, negative biases, depressive realism, healthy optimism ‘Theoretical dualism’
Action-outcome contingency Delta P = ΔP = measure of contingency between binary events p(outcome/action) - p(outcome/no action) = (a/(a+b))-(c/(c+d)) -1 = negative preventative relationship, 0 = no relationship, +1 = perfect generative relationship
Contingency effects on causal judgement Stronger casual judgements with positive than zero contingencies (e.g. Allan, 1980; Wasserman et al., 1993) P(O/A) = 20/20+0 = 1.0 P(O/NoA) = 10/10+10 =.50 ∆P = 1.0-.50 =.50 P(O/A) = 15/5+15 =.75 P(O/NoA) = 15/5+15 =.75 ∆P =.75-.75 = 0 I have some control!I have no control!
Time effects on causal judgements A-O delay Weaken or eliminate perception of cause (e.g., Shanks, Pearson & Dickinson, 1989) Cause determined by action-outcome association. Association formation is competitive process with other cues like context. Increase the strength of Cxt-O association (e.g., Rescorla & Wagner, 1972) Temporal information / knowledge is used to determine whether a causal relationship exists (e.g., Griffiths & Tennenbaum, 2005)
Distinguishing time, context & contingency effects
Our time manipulations A-O delay ITI duration Decrease the strength of Cxt-O association > Stronger causal rating (e.g., Msetfi et al., 2005) Decreased rates of AO pairings over time might weaken causal perception, secondary effect Increase the strength of Cxt-O association Knowledge used to infer absence of causal relationship > Eliminate / decrease perception of cause
Depression effects on causal judgements Depressed people’s judgements more consistent with programmed contingencies than others (e.g., Alloy & Abramson, 1979) Depression: two key cognitive characteristics linked to causal learning – Slowed time perception (Bschor et al., 2004; Gill & Droit-Volet, 2009: Msetfi et al., 2012) > increase time effects – Impaired context processing (Msetfi et al., 2009) and learning (Msetfi et al., 2005) < decrease time effects Test effects of depression (low & high) on causal judgements across a range of time manipulations and a range of conditions
Virtual context causal learning task The house has a stereo system, connected to speakers in every room, which can be controlled using the remote control. Sometimes the remote control doesn’t seem to work. Your job is to test the remote control in the various rooms in the house by trying to turn on the music. Each condition takes place in a distinct room.
Each condition would be composed of a number of experimental trials with a similar structure You can press the button now! Action or no action 3-seconds Music switches on or stays off 2-seconds ITI - waiting…………………
General experimental design (E1-3) Experimental variables (repeated measures) – 2 × A-O delay: short 0s, long 4-s – 2 × ITI length: short 3-s, long 15-s Control: Two versions of each experiment – Fixed Time: All conditions same procedure time 960 sec, trials varied 40, 80, 48, 120 – Fixed Trials: All conditions have the same number of trials, 60, procedure time 480, 720, 1200, 1440 secs Categorisation by levels of depressed mood – Beck Depression Inventory (BDI: Beck et al., 1961) – Median split: Low BDIs ≤5; High BDIs 6+ – Groups matched on age, IQ, digit
Ex 1: Positive contingencies, have control (DP = 1.0|0.5 = 0.5) N=103
Findings with positive contingencies Stronger time effects in the depressed, which are mirrored in context ratings Effect of depression: – Impaired context processing? ✖ – Slowed time perception? ✔ Consistent with slow time magnifying time effects through context associations, also compatible with knowledge based processes Time effects with negative contingencies, delays should: – strengthen context association AND strengthen perception of preventative cause – Weaken perception of any causal relationship according to knowledge based accounts
Ex 2: Negative contingencies, preventative control (DP = 0.5|1.0 = -0.5) N=99
Ex 3: Negative contingency, preventative control (DP =.25|.75 = -0.5) N=100
Findings with negative contingencies Non-depressed – No time effects: delay or ITI Depressed – Some evidence of delay effects but dependent on specific contingency: Less frequent cxt-outcome pairings – Longer delay stronger preventative cause, not elimination of cause. Consistent with associative model
Behavioural data: The story so far using standard causal theory….. Non-depressed groups – Presence of time effects contingency dependent Depressed – Asymmetrical delay effects: weaker cause > positive; stronger cause > negative Time effects stronger & more general for the depressed: slow time magnifies but through effect on context associations Consistent with associative models of causal learning Msetfi, R. M., Wade, C., & Murphy, R. A. (2013, Under revision). Context and time in causal learning: Contingency and mood effects. PLOS ONE.
Psychopharmacological data Serotonergic dysfunction in depression (increased receptor sites in postmortem brains etc etc) Efficacy of antidepressant drugs, but psychological effects unclear, links to emotional processing Serotonin depletion in rats decreases context learning in rats (Wilkinson et al., 1995) & increased release of 5HT in learned contexts (1996) Could the effects we have observed here and previously be located in the serotonin system?
Methodology 1.Reduce levels of serotonin in the central nervous system – Acute tryptophan depletion (ATD) using amino acid mixture at T1 vs placebo at T2 (double blind, order counterbalanced) N = 15 – 5.5 hours rest then causal learning task – Check blood plasma levels of TRP 2.Increase levels of serotonin in the central nervous system – Administer 10mg escitalopram or placebo for 7 days (double blind, mood tested at screen, randomisation, & test) N = 154 – Causal learning task Same causal learning procedure are previous experiments
1. ATD study: data from low BDI scorers only, Ps do have control over the outcome BAL (placebo): action > context but p =.125 ATD: action >> context, p =.016 The ATD effect was located in context ratings, p =.031 Reducing levels of serotonin in healthy people affects control learning through weaker context ratings (enhanced extinction?) Chase, H., Crockett, M., Msetfi, R. M., Murphy, R. A., Clark, L., Sahakian, B. & Robbins, T. (2011). 5-HT Modulation by Acute Tryptophan Depletion of Human Instrumental Contingency Judgements. Psychopharmacology, 213(2-3), 615-623
2. Escitalopram study: Ps do not have control over the outcome Control = Context versus action Behaviour rates of responding Is the relationship between depression and control judgements mediated by low / high rates of behaviour? ( e.g., Blanco, Matute & Vadillo, 2009, 2012) Does drug administration influence these relationships? Depression Higher control value = lower perceived control
2. Escitalopram study: Drug eliminates mediated pathway from Depression > behaviour > Control; This effect was located in judgements made about the context NB: Higher control value = lower perceived control Msetfi, R.M., Kumar, P. Harmer, C. & Murphy, R.A., (2013, to be submitted). The effect of escitalopram and depressed mood on human instrumental contingency judgements. Neurosychopharmacology
Pharmacological data summary Reducing serotonin levels reduced context ratings specifically. When Ps had some control over the outcome, this increased perceived control (unrealistically?) Increasing serotonin levels (ADs) increased levels of behaviour & context sensitivity to reward. When people had no control, this had a knock on strengthening context ratings, increasing feelings of control Effect of serotonin manipulations is situation / contingency specific
Putting it all together Control judgements made by depressed and non- depressed people are well explained by causal learning theories, provided insight into underlying mechanisms – need for theoretical dualism? Very subtle changes in time perception, possibly due to attentional lapse (Msetfi et al., 2012), can have a strong knock on effect on other cognitive processes (context) and feelings of control Time and context processing key components of control learning, located in serotonergic system, and interact with each other & specific situation
Final thoughts Utility of time / context findings in a therapeutic setting? Mindfulness, present awareness: – “Mindfulness means paying attention in a particular way; On purpose, in the present moment, and non-judgmentally.” (Kabat-Zinn, 1994) Mindfulness based therapies have been very effective Implications? – Active ingredients and psychological effects of the mindfulness interventions – Psychological effects of antidepressant drugs “Meditate and Medicate”
Thank you for listening More information: Rachel Msetfi, Department of Psychology, University of Limerick www.judgementexperiment.com/RachelMsetfi/Rachel_Msetfi _Research.html