Post on 16-May-2015
transcript
What are (healthy) habits anyway?
Dr Benjamin GardnerLecturer in Health Psychology
Health Behaviour Research Centre, UCLb.gardner@ucl.ac.uk
30th April 2014
Actions that have come to be automatically triggered by
situational cues(e.g. Maddux, 1997; Verplanken & Aarts, 1999)
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Defining habit
• Learned– through context-dependent repetition (Lally et al, 2010)
• Cue-dependent (stimulus-response)• Automatic
– Do not require intention
– May be initiated without awareness
– Are initiated outside of volitional control– Requires little/no effort (Bargh, 1996)
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How do habits form?Lally, van Jaarsveld, Potts & Wardle (2010)
• 96 participants– Performed a new healthy eating, drinking or exercise
behaviour...
– Once a day, every day
• Each day, participants reported– automaticity of behaviour (i.e. habit)
– whether bhvr performed
• Participants tracked over 12 weeks
Habit formationLally, van Jaarsveld et al (2010)
• Habit
formation best
modelled as
asymptotic
curve
Habit formationLally, van Jaarsveld et al (2010)
• Median time for automaticity to plateau = 66 days
• Range: 18-254 days
• Simpler actions tended to become habitual quicker
Knowledge
Intention
Reasoning
Reflective and impulsive routes to behaviourStrack & Deutsch (2004)
REFLECTIVE
(Associative store)
IMPULSIVE
Perception
of cueBehaviour
• Habits are situated on the impulsive route to behaviour
Habits narrow attention towards the habitual optionVerplanken et al (1997)
• Measure of bicycle use habit
• Hypothetical task: making an unfamiliar journey
• Choose 1 of 4 transport modes (inc bicycle)
• Information available on each mode re 6 attributes– e.g. physical effort, probability of delay, travel time– 24 pieces of information available in total
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• Habitual bicycle users:– chose bicycle more frequently (82%) than did non-habit
pcpts (50%)– used less information (14.45 pieces) than non-habit
users (19.45)
• Similar findings for car users, familiar journeys
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Habits narrow attention towards the habitual optionVerplanken et al (1997)
Habits make alternatives less accessibleDanner, Aarts & de Vries (2007)
• Computerised lab task• Participants shown goal-behaviour combinations
– e.g. ‘relaxing-television’, ‘writing-computer’– Combination shown 1x, 3x or 9x
• Participants then shown goal, followed by:– either the paired behaviour (e.g. relaxing-television)– or an alternative goal-serving behaviour (relaxing-bath)
• How long does it take for participant to recognise the behaviour as appropriate?
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Habits make alternatives less accessibleDanner et al (2007)
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Habits and decision-making
• Habitual actors– Choose their habitual actions more often– Prior to decision-making:
• have less cognitive access to alternatives• use less information on utility of available options• use less information on features of the choice
scenario• think less prior to making decisions
Process model of habitual choiceVerplanken et al (1997)
Habits have two main effects on behaviourTriandis (1977)
1. Habits determines behaviour frequency
2. Habits override conscious intentions:
- where habit is strong, intentions have weakened impact on behaviour
- where habits and intentions conflict, behaviour more likely to be habitual than intentional
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Habits override intentionsGardner (2009)
• 105 car users• University staff• Measures:
– Intention to commute to campus by car over next week– Habitual car commuting to campus
• One week later:– Car use (% journeys to campus done by car)
Habits override intentionsGardner (2009)
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MODERATE HABIT
STRONG HABIT
Habits persist despite conflicting motivesNeal, Wood, Wu & Kurlander (2012)
• 105 cinema-goers• Ostensibly a personality study• Watched and rated 15mins of trailers• Given either fresh or stale (1 week old) popcorn• Stale popcorn rated as less pleasant than fresh
popcorn
Habitual popcorn-eaters will eat stale popcornNeal et al (2012)
Effects of habit on behaviourGardner, de Bruijn & Lally (2011)
• Review of (21) applications of Self-Report Habit Index to diet (14) and physical (in)activity (7)
• On average, habits strongly associated with behaviour frequency
• 8 of 9 tests showed habit to override intentions in predicting behaviour
Problems with traditional views of habitGardner (in press)
• If habit is a form of behaviour, it cannot also be a predictor of behaviour
• Habitual behaviours can be inhibited, so are not inevitably enacted
• Can we impose a concept rooted in animal learning studies on complex human behaviour?
‘a process by which a stimulus automatically generates an impulse towards action, based on learned stimulus-response associations’
Rethinking habit: a new definitionGardner (in press)
Corollaries of this definition
• Habit does not activate behaviour, it activates an impulse towards behaviour– Habit impulses are unconscious unless they are frustrated– Habit impulses can be overridden given sufficient skills, resources and
mental capacity
• Habit is independent of behaviour– When cue is not encountered, habit will not be enacted– A behaviour may not be elicited for some time but can still be habitual– Re-exposure to cues may reactivate ‘dormant habits’
Types of habitGardner (in press)
• Habits of decision– Selecting one behavioural option from several– e.g. choosing to have a coffee
• Habits of performance– Executing the chosen option– e.g. making the coffee
Summary
Habits:•Form through repetition (with reward?)•Activate an impulse towards the habitual option•Focus attention on the habitual option and make alternatives less available•Can override conflicting intentions•Come in two forms
– Habit of decision– Habit of performance
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