The Psychology of food choice

E.P. KösterCenter for Innovative Consumer

Studies (CICS)Wageningen University

The Netherlands

Food choice and psychology

• Food choice and eating and drinking are among the most important human behaviours.

• Psychology is the study of behaviour and its conscious and non-conscious determinants.

• Nevertheless, for a long time eating, drinking and food choice were studied very little by psychology.

• What were the reasons for this neglect and why is it changing now ?

• How will and should this change affect our thinking about food choice and modify our methods to predict it ?

Eating, Drinking and Food Choice

• A seemingly simple, but in fact very complicated behaviour that is influenced by many interacting factors.

• A predominantly learned behaviour with the exception of a dislike for bitter and a preference for sweet and it has very little inborn rules, except for the physiological mechanisms involved in hunger, thirst and satiety.

• A very frequent behaviour that to a large extent is determined by implicit and unconscious intuitive motives, that are hard to investigate.

• A behaviour that has many non-psychological determinants, demanding interdisciplinary research.

• For a long time psychology has rejected explanations implying unconscious determinants of behaviour.

Basic questions and the disciplines that try to answer them

Why : Biology, Physiology, does Motivation and Decision PsychologyWho : Biology, Sociology, eat Social, Differential and Developmental PsychologyWhat : Sensory, Consumer and Food Science, Marketing, and Perception, Memory and Learning Psychology Where: Economy, Sociology, Marketing, Consumer Science,

and Memory, Emotion, Social and Decision Psychology When : Economy, Sociology, Marketing, Consumer Science,

? Memory, Emotion, Social and Decision Psychology

Irritation Boredom Aversion

1.3

Modelling Data-integration

& Co-ordination

0 Intrinsic product characteristics

Perception 1

Psychological factors

3

Situational factors

4

Biological & Physiological

factors 2

Extrinsic product characteristics Expectations

6

Socio-cultural factors

5

Cognition Emotion Motivation

Decision making 3.1

Memory Previous experiences

Learning 3.2

Claims/brandlabel packaging

6.1 Integrity

Sustainability 6.2

Cultural, economical influence

5.1

Appearance Interaction Taste Smell

Texture Trigeminal 1.1

Personality traits Neophobia

3.3

Genetic factors Immuno system Brain imaging

2.1

Age/Gender Physical condition

Sensory acuity 2.2

Time Social surroundings

Physical surroundings 4.1

Coping Assimilation Habituation

4.2

Trust in industry & gouvernement

5.2

Changeing beliefs, norms, habits,attitudes

5.3

Intentionality Signification Attribution

4.3

Risk perception 6.3

Essential factors that influence eating and drinking behaviour and food choice (Mojet)

Oro-gastro- intestinal physiology

2.3

Complexity Adaptation

Dynamic contrast 1.2

Copyright J. Mojet ATO 18-11-2001

Relevant developments in Psychology • Learning and memory

– Incidental vs. intentional; Implicit vs. explicit

• Development – Sensitive periods

• Active vs. Passive perception – How does it function? vs. What can be perceived?

• Thinking, reasoning and conscious control– Intuitive thinking and biases vs. rationality

• Motivation, Emotion and Deciding– Conscious vs. Unconscious

Learning and memory

• Food choice is a learned behaviour. It is mostly based on incidental learning and implicit memory.

• Many different forms of learning are involved in the formation of food habits and depending on the form of acquisition, some food habits are more resistant (+) to change than others (-):– Imprinting and conditioning (pre- and peri-natal)* (+++)– Praise, reward and punishment (parents or others)* (++)– Imitation (parents, peers, idols) (±) – “Sensory” learning (complexity, boredom, exposure)* (++)– Cognitive learning (advice, labeling, risk perception) (-,+)

* Largely implicit and unconscious

Development

• Sensitive periods for stable food habit formation and/or change– Peri-natal (Schaal, Menella, Nicklaus, Haller)– Early childhood (Birch, Rigal, Hanse) – Late adolescence (new “traditions”)*– Child birth (women) *– Retirement *

* Only anecdotal evidence

Active versus passive perception• Psychophysics and sensory analysis have learned

us a lot about the possibilities and limitations of our perceptual systems, but they have told us little about how and to what extent these systems influence and control our actions.

• Goodale and Milner: In vision two independent systems:– Knowing what we see: a ball, a glass– Using seeing in catching a ball or picking up a glass

• Why, in sensory analysis, do we devote much more attention to the sensory properties than to the question what function they have in life?– Are sensory properties essential or are they just learned signals

for other forms of satisfaction, evokers of expectations ?

Intuition and Reasoning• Intuitive thinking: Heuristics and biases in

decision making under uncertainty. Kahneman and Tversky1972, 1973, 1979; Tversky and Kahneman, 1974, 1984. Kahneman 2003.

PerceptionIntuition System 1

ReasoningSystem 2

Fast Parallel Automatic Effortless

Associative Slow-learning

Emotional

Slow Serial

Controlled Effortful

Rule-governed Flexible

Neutral

Process

Content

Percepts Current

stimulation Stimus-bound

Conceptual representations Past, Present and Future

Can be evoked by language

Intuitive judgment: biases and limitations

• People (even trained statisticians) make many mistakes in simple problems, because they do not reason, but use intuitive evidence for fast solutions without checking.

• Example: A baseball bat and a ball cost $ 1.10.The bat costs $1.00 more than the ball. How much does the ball cost ?

Bat and ball

• Intuitive answer most commonly given:Ball = $ 0.10

• Time consuming reasoning solution: Bat + Ball = $ 1.10 Bat = Ball + $ 1.00 (Ball + $ 1.00) + Ball = $ 1.10 2 Balls = $0.10 1 Ball = $ 0.05

1 Bat = $ 1.05

Intuition and corrective control by reasoning• When will corrective thoughts (system 2) intervene?

– When people make errors in the intuitive system and

– When these errors are recognised as errors by reasoning• Corrective operations are impaired by:

– Time pressure – Concurrent involvement in other cognitive tasks – Incongruency with bio-rhytms (morning-evening people)– Being in a good mood

• Corrective operations are positively correlated with:– Intelligence (average in the population)– Need for cognition (low in relation to food)– Exposure to statistical thinking (very low even among

educated people)

• Conclusion: Corrective control occurs seldom

Motivation, Emotion and Deciding• Conscious vs. Unconscious

– Zajonc (1968): Priority of emotion over cognition– Kahneman and Tversky (1972,1973,1979, 2003)– Nisbett and Wilson (1977): Telling more than we know. – Wilson, Dunn(1986):Analyzing reasons vs. Focussing on

feelings. Latter more effective than first– Bargh (1990) Preconscious determinants of social

interaction; Role of automaticity. – Wilson, Schooler 1991): Thinking too much: Introspection

harmful for decisions. – Damasio (1994): Essential role of emotion in thinking and

behaviour. Unawareness and physiological underpinning – LeDoux (1998):Defensive behaviour; “emotional

unconscoius”; physiological underpinning

Food choice behaviour is changing under the influence of exposure

• At first encounter – Specific exploration and novelty reduction– Optimal Arousal Level

• During consumption– Adaptation – Sensory Specific Satiety

• Over longer periods– Change in Optimal Arousal Level– Product boredom– Slowly rising aversion

Perceived Complexity

App

reci

atio

nTheory of Dember and Earl

Optimum

A B

ExperienceAppreciation

Per

ceiv

edC

ompl

exity

OptimumA

B

Theory of WalkerTheory ofDember and Earl

METHOD

• Subjects: N=16851% females, 49% males49% 18-25 years, 51% 26-35 years

• Stimuli7 orange drinks equal in caloric value and of very similar

taste, but varied in complexity by small additions of natural aromas.

• Scaling9-point bipolar rating scales measuring the attributes

Appreciation, Surprising, Ample, Confusing, Fantastic, Elaborated, Shattered, Marked.

• Procedure– Initial rating of all 7 drinks – Repeated exposure to one of the 7 drinks– Final rating of all 7 drinks

Effects of exposure to simple products

5

5,1

5,2

5,3

5,4

5,5

5,6

5,7

5,8

5,9

Simple ComplexType of product

Ap

pre

ciat

ion

Initial rating Final rating

Effects of exposure to complex products

4,8

4,9

5

5,1

5,2

5,3

5,4

5,5

5,6

5,7

5,8

Simple ComplexType of product

Ap

pre

ciat

ion

Initial rating Final rating

Change of the optimal level of complexity

2216404743 2216404743N =

Cases weighted by the number of individual optima

Experimental groups

54321

Mea

n +-

1 S

E r

anks

per

ceiv

ed c

ompl

exity

7

6

5

4

3

2

1

initial measurement

(before exposure)

final measurement (a

fter exposure)

Sensory and consumer research• Almost entirely based on conscious methods

(scaling and questionnaires)

• Bringing people in analytical attitudes by asking them questions that they normally never ask themselves, but just answer in their actions (Do you like this? Is this just right on salt ?)

• Strong adherence to a rational consumer model such as the theory of planned behaviour and asking unanswereable questions about attitudes and intentions. (Wilson, Strangers to ourselves 2002)

Theory of reasoned action or planned behaviour (Ajzen and Fishbein) .

• Based on the idea that behaviour is directly provoked by rational and conscious intentions which are in turn influenced by attitudes and by beliefs about ones’ own values and control possibilities and about the judgments of ‘important’ others.

• Objections to the theory: – Based on (low) correlations (but no scatter plots)– Past behaviour (learning) is a better predictor of actual

behaviour than attitudes or intentions. (Bem 1972: We base our opinions about our attitudes and intentions on past behaviour. Wilson 2002: narratives about ourselves)

– Based on conscious and rational decision making (see Kahneman and Tversky, Zajonc, Damasio, LeDoux and Wilson)

Towards a new way of studying food choice Reductionist vs. Deductionist approach

• Should we continue to dissect human behaviour into many sub-behaviours that can easily be studied in the laboratory and after studying these, try to recombine them ? (Sensory properties, Hedonics, Context etc.)

Or

• Should we try to find ways to study natural complex behaviour in its totality and to deduct the determinants of such integrated behaviour from the effects of variations in the circumstances under which it occurs?

(Observation and Situational Analysis)

Situations• A situation is an event in the life of an individual

in which his personal history is organised in his perception of, and expectations about the things around him. Intentionality is the organiser.– Hunger shows “eatables”– Hunger on a cold winter morning shows …?– Hunger on a hot summer beach shows ….?

• Situations are created by the meaning the subjects unconsciously convey to the surroundings (signification by intentionality). They are not the surroundings themselves.

• Although highly individual, situations are shared

Situational analysis

• Collecting typical eating situations• Segmenting people on the basis of the

frequency with which these situations occur in their life.

• Simulating situations with people that are in different segments. Measuring reactions to foods

• Simulating different situations with people from the same segment or different segments

• Situations can be evoked by stories, images, etc.

Central Location Test vs. Home Party

0

1

2

3

4

5

6

7

8

P Q R S A B C D

Pure spirits Mixed drinks

Hed

on

ic s

cale

val

ues

Central Location Home Party

Simulated vs. real Disco experience

0

5

10

15

20

25

30

35

Non-alcoholic Pure spirits Mixed A Mixed B Mixed C Mixed D

Nu

mb

ero

f ch

oic

es

Simulation Disco

Reductionist vs. Deductionist approach

Reductionist• Isolated behaviours• Experimental manipulation

of single determinants (sensory, hedonic, social)

• Measuring mean effects of and interactions between determinants

• Reconstitution of the total behaviour on the basis of mean group results (?!?)

• Re-integration of data by the experimenter

Deductionist• Total behaviour• Situational manipulation or

situational comparisonwith subject segmentation

• Observation and hypothetical interpretation of behavioural effects and differences

• Verification of interpretations in similar situations with new and/or old subjects

• Integration of behaviour by the individual subjects

Conclusions• More interdisciplinary research and a deductionist

approach is needed to make real progress.• Many of our consciousness-oriented and rather

explicit methods should be replaced or critically evaluated depending on the research goal. (OK in technical research, not in hedonic research)

• More emphasis on research that shows real behavioural or physiological effects is needed. (less correlational research on statements only; observation of actual choice in typical situations rather than just asking about liking or wanting)