DESCRIPTIVE ANALYSIS OF EATING REGULATION IN OBESE AND NONOBESE CHILDREN

Bite rate, sip rate, and concurrent activities of six 7-yr-old children, three obese and three nonobese, were observed at lunchtime over a six-month period. A procedure for decreasing bite rate, putting eating utensils down between bites, was implemented in a multiple-baseline across-subjects design. Sip rates and concurrent activities were observed to assess behavioral covariations. In addition, bite rate and amount of food completed were computed over six food categories to analyze food preferences. Results indicated the control of bite rate across all subjects, with a significant reduction in amount of food consumed. Correlations between the response classes indicated they were at least partially independent. Differences in eating behavior of obese and nonobese subjects were observed for breadstuffs and milk drinking.     

Nonconsummatory and consummatory behavioral CRs elicited by lithium- and amphetamine-paired flavors

Various behavioral CRs elicited by saccharin solution previously paired with either lithium or amphetamine were measured in a series of four experiments. With one conditioning trial, lithium (Experiment 1), but not amphetamine (Experiment 2), produced nonconsummatory behavioral evidence of conditioning in the form of chin-rub CRs; both drugs, however, produced strong flavor aversions. With 3 conditioning trials, lithium- and amphetamine-paired flavors elicited a pattern of agitated activity, characterized by increased general activity, rearing duration, and body temperature, when the flavor was forcibly presented through an intraoral cannula (Experiment 3). When the flavor was presented in a single-bottle test (Experiment 4), 3 conditioning trials produced a similar pattern of agitated activity characterized by increased general activity, rearing (duration and frequency), stretching (duration and frequency), and limb flicking. Although both drugs supported the pattern of increased agitation-related CRs, only the lithium-paired flavors elicited chin-rub CRs (Experiments 1, 3, and 4). The difference between the drug conditions was not the result of a greater saccharin aversion in the lithium-conditioned group than in the amphetamine-conditioned group (Experiment 4). The results are related to findings that suggest that flavor aversions are mediated by a shift in the hedonic properties of the drug-paired flavors.     

A further parallel between selective adaptation and contrast

It is generally believed that selective adaptation effects in speech perception are due to a reduction in sensitivity of auditory feature detectors. Recent evidence suggest that these effects may derive instead from contrast. In a further test of the contrast hypothesis, we conducted two experiments each involving both adaptation and contrast sessions with matching stimulus sets. During the adaptation sessions of Experiment 1, subjects identified two series of velar stimuli varying in voice onset time, [ga]-[kha] and [gi]-[khi], before and after adaptation with of the following stimuli: [ga], [kha], [gi], and [khi]. In the contrast session, subjects identified either of two ambiguous test items (drawn from near the phonetic boundaries of the [ga]-[kha] and the [gi]-[khi] series) following a single presentation of [ga], [kha], [gi], or [khi]. For both the adaptation and contrast sessions, (a) the [--a] test items were more greatly affected (in a contrast direction) by the [--a] than by the [--i] adaptor/context stimuli, and (b) the [--i] test items were not differentially affected by the [--1] and [--i] adaptor/context stimuli. An analogous design was used in Experiment 2, except that the stimulus sets varied in pitch rather than vowel quality. For both the adaptation and contrast sessions, the test items were not differentially affected by the pitch of the adaptor/context stimulus. These parallel results provide further evidence that adaptation effects are actually a form of contrast.     

Conditioned suppression of drinking: A measure of the CR elicited by a lithium-conditioned flavor

The CR elicited by an exposure to a lithium-conditioned flavor CS+ was measured in a paradigm which closely approximated traditional conditioned suppression of licking. Rats were first trained to discriminate between a lithiumpaired flavored solution (CS+) and an equally familiar, but safe, flavored solution (CSc). Then, while they consumed a differently flavored test solution, the rats were intraorally infused with either the CS+ or the CSc flavored solution. The immediate aftereffect of the CS+ exposure on consumption of the Test Solution (TS) measured the CR. The CS+ exposure suppressed the consumption of both a novel flavored TS and an unflavored water TS. The strength of the suppressive CR was influenced by the nature of the TS and by the dose of lhe lithium US.     

An Examination of the Psychometric Properties of Holland's (1985) Vocational Preference Inventory (VPI), Using a British Sample

This study examines the psychometric properties of Holland's Vocational Preference Inventory (VPI) using a diverse UK sample. Whilst an item analysis appears to be satisfactory, the factor analysis reveals seven, rather than the hypothesized six factors. A number of gender and cultural differences were found in the inventory; the bases for these are discussed and suggestions for improving the inventory items for a UK population are offered.     

Prospective factors contribute little to within-session changes in responding

Five rats pressed levers for food delivered by a multiple variable interval 1-min variable interval 1-min schedule. In theunpredictable conditions, sessions were 20, 40, 60, 80, or 100 min long, determined randomly at the beginning of each session. In thepredictable conditions, each of these session durations was presented for 15 consecutive sessions. Rate of responding changed systematically within the session even when the end of the session was unpredictable. This implies that prospective factors related to anticipation of the end of the session are not necessary for producing withinsession changes in responding. Within-session patterns of responding were also similar for the predictable and unpredictable conditions. This suggests that prospective factors contributed little to the form of the within-session patterns under the present conditions.     

Perceived Consensus in Estimates of the Prevalence of Driving Errors and Violations

This paper reports a study of perceptions of the prevalence of certain driving errors and violations in a large ( N = 1,656) sample of drivers. In keeping with previous research on perceptions of social consensus, it was predicted that (a) drivers who reported that they themselves regularly commit these errors and violations would make larger estimates of the percentage of other road users who regularly engage in these behaviors, by comparison with drivers who reported that they do not regularly commit these errors and violations; (b) comparison of estimates of social consensus for own behavior with the actual numbers of respondents reporting that they did or did not engage in these behaviors would show that those who do commit the behaviors regularly would overestimate consensus for their position, while those who do not commit the behaviors regularly would underestimate consensus for their position; and (c) these tendencies to overestimate or underestimate actual consensus for own position would be correlated with the perceived offensiveness to others of the behavior concerned, such that departures from actual consensus would be greater for behaviors rated as more offensive. The results provide strong support for the first two predictions but none for the third; indeed, the degree of over- or underestimation tended to be inversely related to offensiveness. In addition, there were unanticipated but highly consistent sex and age differences in perceptions of the prevalence of the target behaviors, with female and younger respondents making higher estimates than male and older respondents, respectively. The theoretical and practical implications of these findings are discussed.