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Personality Correlates of Responses to Associative Mismatch and to Stimuli
Associated withReward or Punishment
Alan PickeringDepartment of Psychology
Collaborators
Patricia BradyInstitute of Psychiatry
James JeffsLuke Jones
St George’s Hospital Medical School
Outline
• Summarise Gray’s Reinforcement Sensitivity Theory (RST) of personality
• Note mixed results in existing literature
• Present new studies addressing basic issues from scratch
Reinforcement Sensitivity Theory
(RST)
• Bottom-up theory of fundamental personality dimensions
• Psychopharmacological and lesion studies in animals identify two basic systems
Basic Systems of RST
• Behavioural Inhibition System (BIS)
• Behavioural Activation System (BAS)
BIS Characteristics• Inputs: see next slide
• Outputs: inhibition and arousal
• Corresponding personality trait: anxiety
• Neural substrate: septo-hippocampal system
BIS Activating Inputs
• Aversive secondary reinforcers: i.e. conditioned stimuli associated with punishment or frustrative nonreward
• Novel stimuli: i.e. where an associative mismatch occurs
• Innate fear stimuli
BAS Characteristics• Inputs: see next slide
• Outputs: arousal
• Corresponding personality trait: impulsivity (sensation seeking)
• Neural substrate: dopaminergic projection systems
BAS Activating Inputs
• Appetitive secondary reinforcers: i.e. conditioned stimuli associated with reward or relieving nonpunishment
Existing Studies
• Extensive literature since 1970
• Several reviews (e.g., Pickering et al, 1997)
• Usually significant results
• Conflicts across studies
Typical Experiment
1. Take healthy volunteers
2. Measure their trait anxiety and/or impulsivity
3. Expose to BIS and/or BAS activating stimuli
4. Measure behavioural effects of 3 and correlate with scores from 2
Confusing Findings
• Effects of “wrong” personality trait• Unexpected direction of correlations• Variations of traits that correlate• Nature of reinforcers used varies• Unrealistic/complex reinforcers used• Misunderstanding of theory by other
researchers• Some parts of theory untested• Unexpected effects of gender
New Studies 1
• Associative mismatch stimuli
• Stimuli associated with ecologically valid punishments (EVPs)
• Verbal instructions warning of EVPs
Investigated behavioural effects and personality correlates of the following:
New Studies 2
• Additivity of effects
• Associated neural activations via fMRI
Other issues explored were:
Basic Paradigm
• Choice reaction time (RT) task
• Warning stimuli manipulated to create BIS and BAS inputs
• Key stimuli presented to Ss incidentally while doing choice RT
Standard Trial Sequence
+
A
AssociativeMismatch Sequence
+
L
SecondaryReinforcer Sequence
+
A
Choice RTTask Measures
Mean RT and % errors on:
critical trials (associative mismatch or secondary reinforcer)
compared with
immediately preceding standard trials
BIS (Trait Anxiety) Questionnaires
• Eysenck’s Neuroticism Scale: EPQ-N
• Spielberger’s State-Trait Anxiety Inventory: STAI-Y2
• Cloninger’s Harm Avoidance Scale: HA
• Carver and White’s BIS Scale: BIS
Study One: Overview
• Investigated effects of Associative Mismatch (AM)
• 30 healthy volunteers (M/F)• Trait anxiety measures used: STAI-
Y2; BIS; HA• 140 choice RT trials (1-40
practice), including 12 AM trials
Study One: Correlations
RT Difference (AM – Standard)
Measure Corr. p-valueY2 -0.30 0.1HA -0.14 nsBIS -0.35 0.06Comb. -0.32 0.09
Study One: AM RTs By Anxiety Median Splits
0.375
0.38
0.385
0.39
0.395
0.4
0.405
Lo-ANX Hi-ANX
AM
Standard
Study Two: Overview• Investigated effects of AM and secondary
reinforcers (SRs), both aversive and appetitive
• 40 healthy volunteers (male medical students)
• Used preconditioning procedure to create secondary reinforcers
• 350 choice RT trials (1-50 practice), including 6 AM and 24 SR trials
Study Two: Questionnaires
• Trait anxiety measures used: STAI-Y2; BIS; HA; EPQ-N
• A range of measures of BAS-related traits (impulsive sensation seeking)
Study Two: BAS Questionnaires
• Eysenck’s Extraversion and Psychoticism Scales: EPQ-E/P
• Eysenck’s Impulsiveness Scale: I7-IMP• Cloninger’s Novelty Seeking Scale: NS• Carver and White’s BAS Scale: BAS• Introvertive Anhedonia: IAN
Study Two: Preconditioning
• Fully counterbalanced design
• Associates 4 neutral geometric symbols (A-D) with reinforcing events
• Subject immerses hand in ice-water for “unknown period” (actually 45 secs)
• Subject watches award of “random prize” in 50 pence units (actually £3.50)
Study Two: Preconditioning Symbols
Occurs … Associated Reinforcement
A 7 times in first 35 secs cold water immersion
Punishment (Pun)
B twice to signal last 10 secs of cold water
Pun or Relieving Non-Pun (RNP)
C 7 times signalling 50 pence reward each time
Reward (Rew)
D twice to signal end of reward sequence
Frustrative Non-Reward (FNR)
Study Two: Overall RTs
0.32
0.33
0.34
0.35
0.36
0.37
0.38
0.39
0.4
0.41
AM Pun Sym-B Rew FNR
CritComp
Study Two: AM & BIS Correlations I
RT Difference (AM – Comparison)
Measure Corr.p-valueY2 -0.05 nsEPQ-N -0.04 nsHA -0.28 0.08BIS -0.23 nsHA+BIS -0.28 0.08Comb. -0.18 ns
Study Two: AM & BIS Correlations II
RT Difference (Rew – Comparison)
Measure Corr.p-valueY2 -0.04 nsEPQ-N -0.11 nsHA -0.20 nsBIS -0.30 0.06HA+BIS -0.27 0.09Comb. -0.19 ns
Study Two: Rew Regression Results
• DV= RT Diff (Rew – comparison)• Ist Block: Anxiety (HA+BIS)• 2nd Block: BAS traits
Final model:DV= K – 0.35*Anx – 0.32*EPQ-E
Study Two: Pun & BIS Correlations
RT Difference (Sym-B – Comparison)
Measure Corr.p-valueY2 0.28 0.08EPQ-N 0.35 0.03HA 0.14 nsBIS 0.42 0.008HA+BIS 0.31 0.06Comb. 0.36 0.02
Study Two: Pun RTs By Anxiety Median Splits
0.31
0.32
0.33
0.34
0.35
0.36
0.37
0.38
0.39
0.4
Lo-ANX Hi-ANX
Sym-B
Comp
Conclusions• Anxiety is related more strongly to the
arousal, than to the inhibition, produced by associative mismatch (AM)
• Anxiety is related more strongly to the inhibition, than to the arousal, produced by secondary reinforcers associated with punishment (SR-Pun)
• The anxiety measures correlating with AM and SR-Pun effects may differ
Conclusions (continued)• The arousal effect, produced by
secondary reinforcers associated with reward (SR-Rew), is:
associated with extraversion-impulsivity measures
additive to the arousal effect produced by AM