4 - Cognitive biases in Depression PDF

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Cognitive biases in depression...

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Week 7 – Cognition and Emotion Cognitive biases in depression Depression Symptoms: -

Affect (sadness, shame) Cognition (impaired memory and concentration) Motivation (loss of pleasure) Physiology and behaviour (sleep loss, loss of libido)

Depression is the predominant mental health problem worldwide, followed by anxiety, schizophrenia and bipolar disorder Second leading cause of years lived with disability worldwide, behind lower back pain Risk Factors: -

Family history of mental illness Chronic illness Major life events and stress Loneliness, lack of social support Low socio-economic status Female gender Insomnia Psychological factors

Function of depression? Sadness or depression caused by goal loss (Johnson-Laird and Oatley, 1987) Being in a depressed state leads to: -

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Biasing of cognition towards negative information o may help avoid further losses? Anhedonia / reducing motivation to engage in other activities o may help avoid further losses, disengage from unobtainable goals and conserve energy Signalling submission o soliciting help and resources Promoting analytical thinking o focussing on lost goal in order to generate a strategy to produce a new goal, weigh up all pros / cons rather than acting on impulse See Durisko, Mulsant and Andrews (2015)

Beck’s Schema Model of Depression (Beck, 2008; Clark et al, 1999) -

How you see

yourself is processed through a negative schemata, which lead to biases in information processes (attention, interpretative, decision making, memory) -These biases promote attention towards attentions to negative information (selfdeprecating information) -These lead to feelings of depression Frameworks proposed after Beck: -

Williams et al (1988,1997) Cognitive Account Ingram’s (1984) Information Processing Analysis Impaired Cognitive Control Account (Joormann et al, 2007)

Cognitive biases in depression: -

Attentional bias Interpretive bias Memory bias Attentional Bias in Depression

Summary of attentional biases: -

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Fairly limited evidence More evidence for content specific bias (sadness related, not as much threat related) More evidence for delayed disengagement from, as opposed to enhanced engagement, depression related content o Takes longer to disengage from information than to engage with it Some evidence for avoidance of positive stimuli

= See Gotlib and Joormann (2010) and Winer and Salem (2016) for reviews

Study: Gotlib et al (2004) Attentional biases for negative interpersonal stimuli in clinical depression

3 groups of ptps: major depressive disorder (MDD), generalised anxiety disorder, non-psychiatric controls

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Task: pairs of angry-neutral, sad-neutral, happy-neutral faces shown for 1 second followed by a grey dot on either left or right of the screen (dot probe task) DV: time taken to indicate the correct position of the dot = If time taken to see the dot over the sad face is quickest, there is an attentional bias towards negative information -

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(AO3) faces are shown for 1s before disappearing, any attentional bias (if fast) may not have been captured (AO3) with depressed individuals, tend to show biases when stimuli is presented for longer

Results: MDD: most attention towards sad faces, attention avoided towards angry mostly then happy GAD: most attention towards sad faces (so much less than MDD), attention avoided towards angry then happy Control: Most attention towards angry faces, attention avoided towards happy and sad faces

Conclusion: 1) In depressed participants only, attention bias was present for sad (but not happy faces) a. content-specific attentional bias

2) Attention bias towards sadness seems to be specific to depression but not anxiety a. diagnosis-specific attentional bias Interpretive bias depression -

Inconsistent findings for negative interpretive bias More evidence for negative interpretive bias when interpretive or ambiguous situations are made self-relevant Some evidence that individuals may be able to exert control over negative interpretive bias, and when such control is disrupted the bias becomes apparent Some evidence for reduced positive interpretive bias Negative interpretive biases most evident when under high cognitive load

Study: Rude et al (2003) Negative cognitive biases predict subsequent depression Aim: investigate whether cognitive biases can predispose you to depression Measures to assess rate of depression: The Beck Depression Inventory (BDI; Beck, Ward, Mendelson, Mock and Erbaugh, 1961) The Inventory to Diagnose Depression (Zimmerman and Coryell, 1987) The Scrambled Sentences Test (Wenzlaff, 1988) The Scrambled Sentences Task – used to measure ptps tendency to interpret ambiguous information in positive or negative ways ‘winner born I am loser a’ = unscrambled this sentence (I am born a winner / loser) -

The SST was completed under 2 conditions: o 20 sentences to be unscrambled in 2.5min (low cognitive load) o 20 sentences to be unscrambled in 2.5min while remembering a 6-digit number to write down upon completion (high cognitive load)

Results: 18 months later those who unscrambled more sentences in a negative way had higher risk of depression, but only for those in cognitive load task (AO3) demand characteristics, may see both interpretations and choose the more positive one

Conclusions: -

Cognitive vulnerability to depression exists in the form of subtle processing biases, which may be obscured by participants mental control strategies The cognitive load may have disabled strategies that obscured depression-related biases

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Perhaps participants were actively working to avoid a natural tendency toward negative interpretations and these volitional efforts were disrupted by the cognitive load Memory Bias in Depression

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Evidence for an explicit negative memory bias – recall more negative personal memories (autobiographical) Explicit positive memory bias sometimes absent and evidence for these memories not being remembered vividly Some evidence for implicit negative memory bias (stronger when recall and encoding tasks are matched) Tendency to report more overly general memories (linked to rumination over negative themes)

Experimental Memory Paradigms Explicit memory tasks: -

Free recall: can recall without cues, consciously aware of information Cued recall: need a cue / hint to be able to recall things

Implicit memory tasks: -

Word Stem Completion: shown list of words, later presented with first few or last few letters of the words which should be decoded Lexical decisions: shown list of words, presented with a series of words where some were shown earlier, decide asap whether these words are real or not

= Both tasks rely on priming effects where a past experience impacts on subsequent action / performance without consciously remembering this experience / information Study: Bradly, Mogg and Williams (1995) Implicit and explicit memory for emotioncongruent information in clinical depression and anxiety Participants: clinically depressed, clinically anxious and controls Stimuli: depression-relevant, anxiety-relevant, positive and neutral words, and non-words Tasks: -

Explicit memory and implicit memory

DV: the speech of lexical decision (word or non-word)

Results: implicit memory -

Depressed subjects showed larger priming effects for depression-related words than the other 2 groups. These effects were evident in both priming conditions

Results: explicit memory

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No difference between groups in recall of anxious, positive or neutral words But depressed subjects recalled more depression-related words than the other groups Preferential recall of negative comped to positive material is one of the most robust findings in the depression literature

= Depressed people tend to recall depression-related information (sadness) better than nondepressed people, particularly if this information relates to themselves (explicit) Conclusions: -

Clinically depressed patients showed biases on both explicit and implicit memory tasks (contrary to Williams et al 1988 early model) No explicit or implicit memory biases found in anxious participants

Study: Werner-Seidler and Moulds (2011) Autobiographical memory characteristic in depression vulnerability Formerly depressed individuals recall less vivid positive memories Ptps: never depressed and formerly depressed individuals Procedure: First testing session: Autobiographical Memory Test (AMT) – words used to cue memories – negative and positive (failure, hopeless, proud). Ask ptp to write about memory which this word relates to Mood Induction – inducting people into a sad or neutral word state using the Velten procedure (read a series of neutral or sad statements). Also asked to listen to a piece of music (either sad or neutral) Second testing session: another Autobiographic Memory Test

Results: -

Higher vividness ratings of positive autobiographical ratings for never depressed group

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Formerly depressed group shown less recall of positive memories

Conclusions: -

Ratings of vividness for negative memories of never-depressed and formerly depressed individuals didn’t differ only for positive memories Following sad induction, formerly depressed individuals rated their positive memories as less vivid than those never depressed No differences associated with other characteristics of negative and positive memories (e.g. accessibility, sensory detail, emotional intensity, visual perspective and valence) General Conclusions:

Cognitive biases associated with depression: -

Attentional (least associated) Interpretive Memory (most associated)

Biases for negative information Lack of positive bias Importance of self-relevance and self-focus Presence of cognitive bias for negative information and lack of cognitive bias for positive information may lead to sustained negative affect Cognitive biases together with rumination may prevent use of positive memories to repair mood and may minimise use of other strategies such as re-appraisal or problem solving Exam question will be associated with the strength of evidence for the specific biases compared with each other!...