WJEC AS Psychology PY2 - Bennett-Levy and Marteau (1984)

Definitions:

• adaptive trait - increases individual's chances of survival and reproduction; good for fearfulness of dangerous creatures (adaptive trait) to be inherited as enables animals/humans to adapt to environment and be naturally selected
• EEA - 'environment of evolutionary adaptation' time period when humans lived on African plains; dangers they faced led to evolution of fear response

Importance: evolutionary psychology suggests certain fears are adaptive behaviours that helped distant ancestors to survive; if we are extremely fearful of an animal, we try to get away from it and unlikely to be hurt by it, important to understand why we have fears of certain animals and where it originates

Previous Research:

• Seligman (1971) proposed concept of biological preparedness - inherited predisposition to fear certain classes of animals eg snakes; 3 observations support this belief: 1) distribution of animal phobias is non-random; 2) fears of animals not matched by traumatic experiences; 3) fears often appear early in life, reaching peak of 4 yrs old

Previous Research:

• Mineka et al (1980) found that wild reared monkeys showed considerable fear of real, model + toy snakes whereas lab reared monkeys showed mild response to snakes = could be explained in terms of wild monkey's direct experiences which created fear response (operant conditioning); BL+M noted lab monkeys demonstrated direct fear response when snake showed significant movement, suggesting there's not a prepared template to fear snakes but fear of 'snake-like movements'
• Hinde (1974) suggested that other characteristics evoke fear response: novelty and strangeness; further suggested that a large discrepancy between stimulus and organism's model of world is basis for this response; supported by BL+M who treated patients with phobias: found patient's descriptions of what they feared about animals focused on what animals looked and felt like

Aims: BL+M aimed to investigate underlying mechanism (biological preparedness to fear certain stimulus configurations in animals and discrepancies from human form); they predicted the PC of small, harmless animals should be related to the distribution of ratings of fear and avoidance of these animals

PARTICIPANTS: 113 attending a British health care centre

• Group 1: answered 1st qs = 34 f, 30 m; mean age = 35.5 and SD = 16.9
• Group 2: answered 2nd qs = 25 f, 24 m; mean age = 35.1 and SD = 16.4

QUESTIONNAIRES: on 29 small harmless animals/insects; had same perceptual characteristics of harmful animals that create fear in humans, so should be fearful but no threat to humans. if an animal could be considered harmful (jellyfish) pps asked to rate them as if harmless so harm was not a factor in ratings made

QUESTIONNAIRE 1: designed to measure self-reported fear and avoidance of animals/insects; rated on 2 scales:

• fear scale: pps rated fear on 3 point scale
• nearness scale: rated avoidance on 5 point scale of nearness; if animals difficult to pick up, pps imagined they're injured

QUESTIONNAIRE 2: designed to measure self-reported rating of same 29 animals used in qs on 3 point scale: 4 specific perceptual dimensions: UGLY, SLIMY, SPEEDY, HOW SUDDENLY THEY APPEAR TO MOVE

Results from the Experiment:

• rats feared considerably more than any other animal. however may be due to potential harm (eg disease)
• all 4 ratings of perceptual characteristics (PC) correlated with fear and nearness
• slug rated as most ugly and slimy
• lizard rated as most speedy and moves most suddenly
• nearness ratings: females found to be less willing to approach 10 animals than males
• gender differences in fear ratings but no difference in ratings of PC
• men rated less fearful however close correlation between nearness ratings of men and women
• correlations: ratings of ugliness significantly correlated with nearness (0.87) and fear measures (0.82)
• correlations: ratings of sliminess significantly correlated with nearness (0.76) and fear (0.61)

Conclusions from the Experiment:

• PC of animals are important in determining positive or negative approach by humans
• animals with 4 PC less approachable and more fear provoking
• BUT despite effort to remove effect of anticipated harm by instructing pps to rate animals as harmless, harm is important characteristic when comes to rating fearfulness and other PC
• 2 possible mechanisms by which fears inherited:
  - DISCREPANCY PRINCIPLE (Hinde 1974) explains strong relationships between ugliness/sliminess ratings and fear/nearness ratings; pps said judgement of ugliness based on sliminess, hair, colour, no/limbs; all characteristics fit in with discrepancy from human form
  - BIOLOGICAL PREPAREDNESS: Aversive Stimulus Configurations (Schneirla 1965) all significantly correlated with fear when other variables removed; pps also reported other tactile and auditory cues contributed to fearfulness of animals (eg feel of spider)

Conclusions from the Experiment:

• results indicate humans not specifically prepared to fear animals but prepared to approach or fear animal depending on harmfulness and PC
• ugliness based on discrepancy from human (Hinde) and relationship between slimy and fear supports Schneirla

STRENGTHS

• pps not aware of aims of study = no demand characteristics, increases internal validity
• independent groups design reduces order effects (fatigue/boredom/practice), increases internal validity
• sample included roughly equal measures of m/f = can be generalised to men and women, increases population validity
• qs quick, get lots of data, easy to analyse from closed questions

WEAKNESSES

• mean ratings showed disproportionate amount of fear for rats, due to potential harm, attempt to remove harm factor failed, pos. in other animals
• correlation but difficult to establish cause-effect between variables, so could be other factors linked to fear other than PC
• self-report qs - subjects can lie or give socially desirable answers/exaggerate
• independent groups design - could be individual differences, decreases validity
• done in British health care centre = ethnocentric, difficult to generalise to other countries/cultures, decreases population validity

1. Seligman (1971) SUPPORTS

• 2-4 small electric shocks enough to induce phobia to pictures of spiders/snakes
• however larger series of shocks required to induce phobic response to pictures of flowers

SUPPORTS BL+M as suggests animals (stimuli) that are Fear Relevant (FR) are more easy to associate with fear than Fear Irrelevant (FI) stimuli, consistent with preparedness, HOWEVER research has been unreliable in humans, fails to identify which physical features increase preparedness or indicate FR, or modern phobias like syringes

2. Ohman (2000) SUPPORTS

• conditioned fears to FI stimuli like houses/flowers however became extinct when aversive stimuli (electric shock) stopped
• however fear response persisted after electric shocks stopped in FR stimuli like snakes/spiders

SUPPORTS as suggests association of FI stimuli made with aversive stimuli quickly lost (less survival value) but FR associations harder to unlearn as more survival value

3. McNally (1987) CONTRADICTS/SUPPORTS

• reviewed no. studies and suggest lots of evidence about extinction of FR stimuli (unlearning) was slower than FI stimuli
• however acquiring (learning) fear of FR or FI stimuli was no significantly different

Suggests we are not biologically prepared to learn to be scared of some stimuli more than others, but once learnt FR stimuli is harder to unlearn

4. Davey (1995) DEVELOPS

• suggests expectancy bias rather than evolutionary explanation of preparedness for certain stimuli
• expectancy bias is expectation that FR stimuli (such as dangerous situations, past unpleasant experiences) will produce negative consequences in future so is harder to unlearn, once learnt

DEVELOPS as explains inconsistent data, such as modern phobias, which would not be possible to inherit, as developed fairly recently in evolutionary past, doesn't rule out evolutionary explanations of certain stimuli