Pecking and feeding in chicks

Pecking is not controlled by nutritional state in a newly hatched chick, but by 3 days posthatch it normally is. This paper tests the hypothesis that first a chick must learn that pecking leads to ingestion; then, other (nonlearned) processes are automatically responsible for differential pecking rates to nutritive and nonnutritive items. The first experiment shows that experience pecking and ingesting sawdust is sufficient for differential pecking to develop. The second experiment shows that swallowing without pecking (using a force-feeding technique) does not lead to differential pecking. The third experiment shows that pecking without swallowing (using sand glued down to the floor) also does not lead to differential pecking. Finally, the last experiment shows that food deprivation affects pecking rate only after pecking and ingestion have been associated. These results support the above hypothesis that pecking followed by ingestion leads to the “attachment” of the pecking response to the feeding system. Motivational independence of pecking and the hunger system, the association of pecking with ingestion, and the development of behavior systems are discussed. It is concluded that the function of a behavior may not be related to its causes.     

Differences in women's and men's responses to domestic space

Men and women were surveyed about feelings toward and activities occurring in their own living rooms, kitchens, bathrooms, and bedrooms. In general, women recalled more activities than men did over all the rooms. For the living room, women were more concerned with room size and feeling cramped. For the kitchen, women described baking, ironing, and clothes washing more frequently and showed more concern with cooking and tidying up. However, men made more references to eating when describing the kitchen, showed greater concern with design, decorating, and building for the kitchen and bedroom, and made more explicit references to use of the bathroom toilet. Other results did indicate that women and men were both highly sensitive to and aware of their living space.This research was conducted while the author was a research fellow at the Psychology Department of Kings College, University of Aberdeen in Scotland. The author wishes to thank the following individuals for their help during various stages of the project: Christopher Creed, Philip Greenway, John Simon, and Derek Wakelin.     

Transitioning into and out of large-effect drinking in young adulthood

As individuals age beyond the college years into young adulthood, many exhibit a tendency to moderate or "mature out of" alcohol involvement. The current study classified effect-drinking statuses in young adults and examined transitions among statuses using latent transition analysis, a latent variable state-sequential model for longitudinal data. At 3 occasions over 7 years (Years 1, 4, and 7), 443 men (47%) and women (mean age of both at baseline = 18.5 years; 51% with family history of alcoholism) responded to 3 past-30-day items assessing drinking and subjective effects of drinking: whether the respondent drank alcohol, felt high, and felt drunk. Latent statuses included abstainers (14% at Year 1), limited-effect drinkers (8%), moderate-effect drinkers (23%), and large-effect drinkers (54%). Respondents with family history of alcoholism were less likely to transition out of large-effect drinking than those without family history. Men exhibited more severe initial effect-drinking statuses and lower transition probabilities into less severe effect-drinking statuses than women.     

Learned resourcefulness, drinking, and smoking in young adults

The purpose of this study was to examine the relationship between learned resourcefulness and two common addictive behaviors, namely, drinking and smoking. Male and female college students (N = 175) completed the Self-Control Schedule (SCS), the Quantity-Frequency-Variability questionnaire, and a smoking history form. Learned resourcefulness was related to self-reported patterns of alcohol consumption; specifically, heavy drinking subjects were lower in learned resourcefulness than were light and moderate drinkers who, in turn, were lower in learned resourcefulness than were infrequent drinkers and abstainers. Learned resourcefulness was only modestly related to smoking, with students who had never smoked evidencing somewhat higher learned resourcefulness than ex-smokers and current smokers. Overall, these data provide correlational support for the notion that learned resourcefulness may protect young adults against substance abuse.     

Psychological predictors of young adults' drinking behaviors

Path analyses using data from 72 men and 78 women between 22 and 32 years of age compared two models linking personality (conflict resolution styles, intimacy maturity, and occupational identity status) and social roles (family and work status) to young adults' alcohol use. Poor conflict resolution skills and less adult work statuses best accounted for men's excessive drinking, and problems with intimacy best accounted for women's use of alcohol to alleviate emotional distress. In addition, poor conflict resolution skills partly mediated the effects of parent's drinking on son's alcohol consumption. Occupational identity status and intimacy maturity correlated with men's use of drugs rather than men's alcohol use.     

Recognition of problem drinking among young adult prisoners

Alcohol is a preventable cause of illness, offending and other adversities worldwide. Prisoners are especially vulnerable. The aim of this study was to test the hypotheses that younger adult male prisoners are more likely to be hazardous drinkers than their older peers, but less likely to recognize this. The study cohort comprised 100 male prisoners aged 18-20 years and 157 aged 21 and over, who were interviewed and completed standard alcohol and drug questionnaires just after reception into prison. It was found that younger men were significantly more likely to be hazardous drinkers than their older peers but less likely to recognise this, even at scores on the Alcohol Use Disorders Identification Test (AUDIT) indicating dependency. They were also less likely to experience withdrawal symptoms, the main factor associated with problem drinking recognition at any age. Younger prisoners were less likely to be depressed, more likely to rate their social support as good and less likely to be dependent drug users. We conclude that reliance on younger prisoners to recognise their hazardous drinking would identify about one-fifth of them. With a lower likelihood of withdrawal symptoms than older men, they are probably still metabolizing alcohol more effectively. Given their similarities to older prisoners in terms of any previous imprisonment and likely personality disorder, formal screening for hazardous drinking might prevent decline into problem drug use, depression, reoffending, re-imprisonment, and social disconnection.     

Spontaneous generalization of abstract multimodal patterns in young domestic chicks

From the early stages of life, learning the regularities associated with specific objects is crucial for making sense of experiences. Through filial imprinting, young precocial birds quickly learn the features of their social partners by mere exposure. It is not clear though to what extent chicks can extract abstract patterns of the visual and acoustic stimuli present in the imprinting object, and how they combine them. To investigate this issue, we exposed chicks (Gallus gallus) to three days of visual and acoustic imprinting, using either patterns with two identical items or patterns with two different items, presented visually, acoustically or in both modalities. Next, chicks were given a choice between the familiar and the unfamiliar pattern, present in either the multimodal, visual or acoustic modality. The responses to the novel stimuli were affected by their imprinting experience, and the effect was stronger for chicks imprinted with multimodal patterns than for the other groups. Interestingly, males and females adopted a different strategy, with males more attracted by unfamiliar patterns and females more attracted by familiar patterns. Our data show that chicks can generalize abstract patterns by mere exposure through filial imprinting and that multimodal stimulation is more effective than unimodal stimulation for pattern learning.     

Cardiovascular responses to agency and communion stressors in young women

Theory and research (Helgeson, 1994) suggest that women are particularly responsive to communion stressors (i.e., social relationship concerns) as opposed to agency (i.e., achievement and dominance concerns) and that women low in the trait of agency are vulnerable to stress. To test these hypotheses, 60 undergraduate women interacted with a pre-recorded partner; one-third provided support to an interaction partner (i.e., communion stressor), debated current events (i.e., agency stressor), or described a typical day (i.e., control task). Compared to controls, the debate task evoked greater systolic blood pressure and heart rate reactivity and related autonomic changes. Compared to controls, providing support evoked larger increases in cardiac sympathetic activation and reduced vascular resistance. Low levels of trait agency were associated with greater CVR overall. Hence, agency and communion stressors had distinct psychophysiologic effects. Although both tasks heightened reactivity, the agency task evoked cognitive and physiological responses consistent with threat, whereas the communion task evoked a pattern consistent with challenge.     

Use of kind information for object individuation in young domestic chicks

In this paper, we studied the ability of newborn chicks to use kind information (sortal objects) provided by social and food attractors to determine the number of distinct objects present in an event (object individuation). Newly hatched chicks were reared with five imprinting objects and were fed mealworms. Chicks’ spontaneous tendency to approach the larger group of items was exploited. At test, on day 2 post-hatching, chicks observed two events in which objects, differing in kind, were each hidden behind one of two identical screens. Approaching either screen was considered a preferential choice. In Experiment 1, chicks presented with two social versus two food attractors did not exhibit any preference. In contrast, in Experiment 2, when chicks saw two different attractors (one social and one food) hidden behind a screen and one attractor hidden twice (i.e. moved back and forth two times) behind the other screen, they spontaneously approached the two different attractors rather than the single one seen twice. An explanation based on the preference for the more varied set was ruled out in Experiment 3: chicks did not preferentially choose between two different versus two identical objects when both groups were simultaneously presented. Results suggest for the first time that a non-human species uses kind information for individuating objects in a cross-basic-level contrast (i.e. food and social items) with minimal experience. As social and food stimuli differ in property as well as in kind information, the alternative explanation accounting for use of property information alone is also discussed.