The effects of pre-exposure to food cues on the eating behavior of restrained and unrestrained eaters.

摘要

Three studies were conducted to examine the response of restrained and unrestrained eaters to pre-eating exposure to food cues. Study one investigated the effect of pre-exposure to two types of food cues (olfactory and cognitive) on food intake by restrained and unrestrained eaters. Subjects were exposed to either no cue, an olfactory cue, a cognitive cue, or a combination of the two food cues for ten minutes prior to eating. Restrained eaters ate significantly more than did unrestrained eaters after exposure to the food cues. Study two found that restrained eaters responded to pre-eating exposure to food cues by eating more, but only when the food they eat is the same as that to which they have been exposed. Intake of a food that differed from the pre-eating food cue was not significantly different from food intake after no prior exposure. Unrestrained eaters showed little differential eating response to either food cue. Study three tested whether the specificity of response to a food cue is controlled by what subjects are led to expect about the foods that they will be tasting. Expectancies played a significant role in determining food intake as indicated by the finding that restrained eaters ate significantly more when they were expecting to taste the same food as the preceding cue relative to restrained eaters who were expecting to taste a different food, even though the food that they eventually ate, chocolate chip cookies, was the same in both conditions Unrestrained eaters' food intake was not significantly affected by these manipulations.;Pre-eating exposure to food cues evoked increased food intake in restrained subjects. This effect may be due to a history of classically conditioned responses to food-associated cues formed during critical periods of food deprivation (dieting). Unrestrained eaters, who do not restrict their food intake, are less likely to form such strongly conditioned associations and therefore are not as influenced by external food stimuli. Food cues may act as a signal to eat and also convey a message of what to eat to receptive individuals such as those with a history of food deprivation.