Central-place foraging by Rattus norvegicus on a radial maze

We studied central-place foraging in rats (Rattus norvegicus) by placing food items that varied in size and weight at the ends of a 4-arm radial maze. In Experiments 1-3, rats increasingly tended to carry food to the center of the maze as the size of those items increased. Very large food items often were hoarded in the center. Rats consumed food faster on the arms than in the center, and rats traveled faster when carrying food than when not. Blocking arm entrances increased travel time between the center and the arms and decreased food carrying at every item weight except the largest. In Experiments 4-6, important conditions that influence the degree of food-carrying behavior were discovered; these were the intersection of maze arms, the presence of a conspecific, and the use of open vs. closed maze arms.     

Timing multimodal events in pigeons

The peak procedure was used in two experiments to study pigeons' ability to time multimodal events. In the first experiment, birds were trained to time a single event consisting of a 9-s tone or light followed by a 21-s fixed interval associated with a signal of light or tone (signal of the other modality). On occasional empty trials, different lengths of the first signal were followed by a long period of the second signal. Peak response times as a function of the duration of the first signal were linear and had a slope of close to one in all birds. This indicates that the birds were timing only the second signal. In a second experiment, two complex events were used in training. One consisted of a 9-s tone or light followed by a 21-s fixed interval associated with a light or tone. The other consisted of a 21-s tone or light followed by a 9-s fixed interval associated with a light or tone. Different durations of the first signal were again used on empty trials. Peak response times as a function of the duration of the first signal were again linear in all birds. The slope of the function was less than one but greater than zero for 3 birds. This indicates that these birds were partly timing the entire complex event of 30-s duration and partly timing only the second signal of the event. A model is proposed in which the bird takes as a criterion for timing a weighted average of different target criteria. Comparisons with the performance of rats are made.     

Intervening causation and the mitigation of responsibility for harm doing II. The role of limited mental capacities

The present study investigated (i) the conditions under which the proximal cause of an event affects judgments of a distal cause, (ii) the capacities persons need to be held responsible for their actions, and (iii) the relationship between judgments of causation, blame, and restitution. Subjects read about situations in which an initial act, in combination with a later behavior by a second person, produced harm. The age and mental state of the second person were varied. It was found that cause and blame assigned to the initial action was greater when the second person was a child or mentally disturbed, as compared to a sane adult. Causal and moral responsibility were related to the understanding, reasoning capacity, and ability to control behavior of the person judged. Finally, support was obtained for an entailment model of the relations between judgments of causation, blame, and restitution.     

The escape-to-Israel syndrome: Variations on the geographic cure

The author conceptualizes a pattern of thought and behavior that can be called the escape-to-Israel syndrome. This pattern is a contemporary variety, appearing primarily in the Jewish population, of the geographic cure: that is, one can solve one's personal dilemmas by moving from one place to another. The syndrome is characterized by a tendency to idealize life in Israel. This idealization, and the viewers' fantasy of their own future in Israel, deflect solid confrontation with genuine personal problems. If, in fact, they do move to Israel, they may experience shock and trauma at the gap between expected reality and the discovered one. This may only compound their emotional difficulties.The author wishes to express his gratitude to Professor Shamai Davidson, Clinical Director of the Shalvata Mental Health Center, Hod HaSharon, Israel, for his critical comments during the preparation of this article.     

The perceived support network inventory

The development and psychometric investigation of the Perceived Support Network Inventory (PSNI), a measure of perceived social support, is described. A group of 146 introductory psychology students participated in a test-retest study design that collected reliability, internal consistency, and construct, convergent, and discriminant validity data on the scale. In addition, a contrast group of 28 Counseling Center clients was administered the PSNI. Test-retest reliability of the PSNI total score and subscale scores ranged from .72 to .88. Internal consistency for the PSNI was .77. Construct validity estimates ranged from .21 to .57. Convergent validity estimates varied from -.25 to .20. Discriminant validity estimates varied from -.11 to .19. Sample differences between introductory psychology student mean PSNI total and subscale scores and Counseling Center client mean PSNI total and subscale scores proved significant. Recommendations for subsequent research and future application are offered.     

Effect of classical conditioning on an internal clock

Six experiments with rats used a psychophysical choice procedure to study the internal clock used to discriminate duration. They investigated if the clock is sensitive to the signal value (associative strength) of a stimulus. The experiments involved two types of trials. On choice trials, a stimulus lasted a short (e.g., 3 s) or long (e.g., 12 s) duration; then the rats chose between two levers. The rewarded choice depended on the duration of the stimulus. On conditioning trials, the stimulus used on choice trials was presented, but it ended without food (extinction trials) or with food (pairing trials) regardless of what the rat did. The main stimulus minus accuracy with the long stimulus. Experiment 1 showed that extinction trials increased short bias relative to training without conditioning trials or to training with pairing trials. The rest of the experiments tested explanations of these results. The same results were found when extinction trials were the same duration as the short stimulus (Experiment 2), when extinction trials were a random duration (Experiment 5), and when the signal value of the conditioned stimulus was changed in another way (Experiment 6). The effect of conditioning trials was modality specific (Experiments 3 and 4). Of the explanations considered, the best one--the only one not contradicted at least once--is that changing the signal value of a stimulus changes how the clock times the stimulus. Reducing signal value reduces the measured duration.     

Levinsonian studies of women's adult development

We reviewed four unpublished dissertations that used Levinson's theory to study women's adult development. The 39 biographies presented in these studies suggested that the women progressed through the same developmental periods as had men in Levinson's study and at roughly the same ages. Although the timing of the periods and the nature of the developmental tasks appeared to be similar, the ways of working on these tasks as well as the outcomes achieved were different. These differences are understood in part as consequences of the greater complexity of women's dreams and the problems encountered in living them out.     

Interaction of emotion and cognition in word recall

Summary Previous research has demonstrated that the emotional properties of words and their imaginability affect their recallability and that verbal material is recalled better when it is related to subjects' current concerns. This study investigates the extent to which this effect of emotion on recall varies as a function of cognitively controllable inference processes and examines the relation of the effects of emotion to those of imaginability and concern-relatedness. Forty different words were presented visually under one of six orienting conditions that varied according to what the subject was asked to rate: their length, pronounceability, concreteness, defineability, the strength of emotion elicited by the word, and the relation of the word to personal concerns. Subjects were then asked to write as many words as they could recall. Words that aroused stronger emotion and were easier to represent in imagery were recalled better than emotionally less arousing and imaginally less evocative words, regardless of the nature of the orienting task. The evidence suggests that the emotional properties of words are evaluated automatically in an early processing stage, without requiring subjects to reflect on word content. Emotional arousal appears to mediate the effects of current concerns on recall. It is correlated with but appears to function independently of word imaginability.     

Awareness of the response after feedback training for changes in heart rate and sudomotor laterality

What is the relation between the ability to control visceral responding on a biofeedback task and the ability to report behaviors actually contributing to this performance? Subjects received biofeedback training for unidentified visceral responses and then gave written reports about what they had done to control the feedback displays. Independent judges were given these reports and, on the basis of knowledge about activities known to contribute to visceral activity, were asked to determine the visceral responses for which the subjects had been trained. The reports of subjects who succeeded at bidirectional control of heart rate (Experiment 1) or sudomotor laterality (Experiment 2) showed awareness of behaviors related to feedback as assessed by this procedure, whereas the reports of subjects who failed at bidirectional control did not. Subsequent experiments indicated that these results did not depend on a learning strategy that might have been specific to the initial studies. These findings call into question the view that people are unaware of what they have done to produce the response after training on biofeedback tasks. Earlier studies reporting lack of awareness in biofeedback are discussed in light of factors that affect the measurement of biofeedback learning and response awareness.     

Hyperactive behavior in english schoolchildren: A questionnaire survey

The differences in apparent prevalence of childhood hyperactivity between England and North America are more than 20-fold. This paper seeks to illuminate the reasons for the difference by applying a standard measure [Conners Teacher Rating Scale] to 437 English schoolchildren, aged 6 to 9 years, and comparing them with published surveys from the United States and Australasia. The rating scale had moderate interrater reliability and stability over time; it distinguished between children referred for psychiatric treatment and normal schoolchildren. Component analysis yielded a factor of hyperactivity-inattentiveness, distinct from conduct disorder. The mean hyperactivity scores of English children were higher than in most U.S. surveys but lower than in New Zealand. The national differences in rates of diagnosed hyperactivity are likely to reflect diagnostic inconsistency rather than true differences in children's behavior.