Behavioral thresholds for tones during infancy

An adaptive up-down tracking procedure was used in combination with a visually reinforced head turn response to examine auditory sensitivity for 500, 2000, and 8000-Hz tone bursts in infants 6 to 18 months of age. Six- and 10-month-old infants were tested with headphone presentation of stimuli, while 10-, 14, and 18-month-olds were tested in sound field. Infant threshold estimates for both headphone and sound field were within 15 dB of adult comparisons for all frequencies and age groups. Six-month-olds were significantly less sensitive to the 8000-Hz tone than to either of the lower frequency stimuli, but older infants demonstrated approximately equal sensitivity for all three frequencies tested.     

The self-serving function of hypochondriacal complaints: physical symptoms as self-handicapping strategies

The present experiment tested the hypothesis that hypochondriacal individuals commonly use reports of physical illness and symptoms as a strategy to control attributions made about their performances in evaluative settings (i.e., self-handicapping strategies). Specifically, it was predicted that hypochondriacal individuals would report more recent physical illness and complaints and more current physical symptoms in an evaluative setting in which poor health could serve as an alternative explanation for poor performance than would either individuals in an evaluative setting in which poor health was precluded as an excuse or individuals in a nonevaluative setting. As predicted, results supported this self-protective pattern of complaints in a hypochondriacal sample but not in a nonhypochondriacal group. The self-protective role of hypochondriacal behavior is discussed in relation to other theory and research on the nature and treatment of hypochondriasis.     

Effects of d-amphetamine on self-aggression and posturing in stumptail macaques

The behavioral effects of d-amphetamine sulfate were studied in adult male stumptail macaques living within a large heterogeneous group in an outdoor enclosure. Among five subjects that received a range of doses (.01 to .3 mg/kg), d-amphetamine increased self-aggressive behavior and abnormal posturing in subjects that exhibited these types of behavior prior to drug administration, but it had no effect in subjects not exhibiting those activities in the absence of the drug. For the former subjects, the dose-effect curves for self-aggression were of an inverted U-shape analogous to the effect of d-amphetamine on schedule-controlled behavior. Over the range of doses studied, the curve for abnormal posturing was monotonic. The data indicate that d-amphetamine can have effects on untrained behavior in individual animals in a quasinatural environment that are qualitatively and quantitatively similar to the behavioral effects observed in other laboratory environments, and that d-amphetamine does not evoke or increase a behavioral response in individual subjects that do not exhibit the response in the absence of the drug.     

Does reward depletion influence spatial memory performance?

If spatial memory tasks are considered as foraging problems, it can be predicted that rats' difficulty in learning a win-stay task—revisiting part of a maze where food has recently been found—should be partly overcome if the food is not fully consumed at the first visit (nondepleted reward) rather than being all eaten (depleted reward). Three experiments confirmed and further analysed this result. Experiments 1 and 2 showed that it does not depend on the amount of food initially found; nor is win-stay performance affected by the amount of food actually eaten. Experiment 3 suggested that the effects of nondepleted reward are mainly due to the animals' being interrupted while eating, and very little to the fact that uneaten food is left behind. The results are discussed with regard to their implications for learning theory, and for the application of foraging theory to learning and memory experiments.     

Choice reaction time with a random foreperiod

Choice reaction latencies were measured at three different a priori probabilities for two stimulus alternatives. Unlike the results of some other studies, the mean latency of a given response was nearly the same whether the response was correct or incorrect. The discriminable stimuli were a 1000- or a 1700-Hz tone presented at 70 dB SPL. Latencies and standard deviations, based on about 17,000 observations, are reported for three observers. The data are compared with predictions of the optimum sequential model of Wald and Stone and two modifications of that random-walk model, one proposed by Link and Heath and the other proposed by Laming. Fast-guess analyses were also carried out. The three-parameter version of either the sequential or the modified random-walk models provided reasonably accurate predictions of the mean data for each observer. The parameters estimated by the fast-guess analysis were unrealistic. There are three obvious differences between this experiment and most previous choice reaction-time experiments. First is stimulus modality#x2014;we used an auditory signal, whereas most of the previous studies used a visual signal. Second, the observers practiced more in this experiment than in most previous experiments. Finally, there was a random foreperiod with a heavy penalty for anticipations. One or more of these factors is the probable reason for the discrepancy between our results and those of previous studies.     

Perceptual deprivation,extraversion—introversion and the autokinetic phenomenon

The present study examines the relationships between perceptual-deprivation tolerance and three variables: extraversion, the autokinetic (AK) phenomenon and field-dependence. In addition, the relationship between extraversion and autokinesis (AK) was investigated. Thirty-three male subjects were subjected to 3 hr of perceptual deprivation and, in addition, their scores on each of the three independent variables were obtained. It was found, as hypothesized, that perceptual-deprivation tolerance was negatively related to extraversion and positively related to the intensity of the AK effect. Field-dependence was not related to perceptual-deprivation tolerance. The correlation between extraversion and the autokinetic effect was significant but moderate. The nature of the relationship between these two variables is discussed.     

The relationship between the probability assessor and the outcomes of an event as a determiner of subjective probability

Two experiments were conducted in which 58 subjects assessed the probability of occurrence of positive and negative events. Two types of probabilities were assessed. The first was the probability that an event would occur, influencing the assessor him/herself (SPE). The second was the probability that the same event would occur to someone else, not influencing the assessor (SNPE). Six patterns of assessments were observed. Most of the subjects assessed SPE to be higher than SNPE for positive events and SNPE to be higher than SPE for negative events. In the first experiment SNPE was assessed in regard to someone very close and similar to the assessor while in the second experiment SNPE was assessed in regard to a less-defined “else”. In the latter case the differences between SPE and SNPE were more prominent than in the first. The explanation was given in terms of motivational factors and the availability heuristic.     

The relative efficacy of simulation experiments

A complex in-basket simulation and a paper-and-pencil scenario experiment were used to study relationships between organizational leadership and gender. Separate samples completed identical attitude instruments in the independent studies. Analysis revealed that substantially more of the total variance was accounted for in the simulation study than in the scenario investigation. Also, more overt, gender-based responses were observed in the scenario study. It was concluded that social simulation may tap a deeper level of psychological process and may elicit more subject involvement than typical experimental methods. Thus, the more complex procedures of the simulation, as compared to those of a typical method such as a scenario study, are justified in the study of organizational behavior.     

Framework for formal ontology

The discussions which follow rest on a distinction, first expounded by Husserl, between formal logic and formal ontology. The former concerns itself with (formal) meaning-structures; the latter with formal structures amongst objects and their parts. The paper attempts to show how, when formal ontological considerations are brought into play, contemporary extensionalist theories of part and whole, and above all the mereology of Leniewski, can be generalised to embrace not only relations between concrete objects and object-pieces, but also relations between what we shall call dependent parts or moments. A two-dimensional formal language is canvassed for the resultant ontological theory, a language which owes more to the tradition of Euler, Boole and Venn than to the quantifier-centred languages which have predominated amongst analytic philosophers since the time of Frege and Russell. Analytic philosophical arguments against moments, and against the entire project of a formal ontology, are considered and rejected. The paper concludes with a brief account of some applications of the theory presented.