Exploring Cross-Group Discrimination: Measuring the Dimensions of Inferiorization1

We describe a theoretical framework that identifies similar themes across the reported experiences of historically stigmatized groups. Inferiorization is a function of the confluence of stigma, context, and associated cultural myths. A self-report measure of inferiorization was applied to college-student samples of African Americans, White women, gay men and lesbians, people with disabilities, and, as a control, a White male comparison group (total N= 263). Stigmatizable people tended to report more frequent inferiorizing events than generally nonstigmatizable people. Deviations from this pattern were explained by the contextual and stigma-related specificity of inferiorization and the presence or absence of associated cultural myths. Inferiorization describes a general social process that remains sensitive to the experiences of specific groups and to the contextual nature of stigmatization.     

Selective changes of sensitivity after adaptation to simple geometrical figures

Using simple geometrical figures, the effect of adaptation upon sensitivity to figures of the same or different form was investigated. The adapting stimuli (blank white field, contour triangles, or circles) were presented for 1, 5, 30, or 60 sec. The test stimuli were always triangles, presented for a short exposure time at .1, .2, .4, .8, and 1.2 sec after the offset of the adapting pattern. The threshold duration of the test stimuli was measured. It was found that both adapting patterns raised the threshold above that measured for adaptation with the blank white field. But it wss only for the pair “adapting triangles-test triangles” that an increase of the time of adaptation beyond 5 sec resulted in an increase of this effect. This suggests that selective lowering in sensitivity during prolonged viewing of some figures may develop. The effect disappeared after about 1.2 sec following an exponential curve.     

Biochemistry of nervous dogs

Previous behavioral studies on a nervous strain of pointer dogs have demonstrated genetic as well as environmental components in the nervous trait. Behaviorally these animals are extremely hypervigilant, with an apparent low threshold to fear and show strong avoidance of humans. In addition, the nervous E strain dogs show an unusually high degree of sensitivity to the mange mite. These observations led to the initiation of studies to determine whether differences exist between the normal A strain and the E strain of dogs at the biochemical level. Although a number of biochemical parameters examined have shown no statistically significant difference between the two strains, the modification of serum creatine phosphokinase (CPK) activity in response to various types of stress does differ as a function of strain—the nervous dogs being less, not more, responsive than the healthy dogs. When not specifically subjected to stress the serum CPK levels in both strains were highly related to age. Significant differences between strains also have been demonstrated in the cerebrospinal fluid acetyl cholinesterase activity levels in older animals. Tryptophan loading experiments, conducted in the presence and absence of the monoamine oxidase inhibitor, tranylcypromine, resulted in no readily observable behavioral modification of either strain and the response of the cerebrospinal fluid 5-hydroxyindoleacetic acid levels was similar for the two strains.     

Searching beneath the shelf in macaque monkeys: evidence for a gravity bias or a foraging bias?

The reasons underpinning search biases in 2 species of macaque monkeys (Macaca mulatta and Macaca arctoides) were explored over the course of 3 experiments requiring monkeys to search for a hidden food reward. The results reveal that monkeys are adept at exploiting perceptual cues to locate a food reward but are unable to use physical constraints such as solidity as cues to the reward's location. Monkeys prefer to search for a food reward beneath a solid shelf, not because they have an expectation that the reward should be there, but rather because, in the absence of usable cues, this bias emerges as a default search option. It is hypothesized that this bias may have its roots in a history of competition for food resources.     

Cholinergic septo-hippocampal innervation is required for trace eyeblink classical conditioning

We studied the effects of a selective lesion in rats, with 192-IgG-saporin, of the cholinergic neurons located in the medial septum/diagonal band (MSDB) complex on the acquisition of classical and instrumental conditioning paradigms. The MSDB lesion induced a marked deficit in the acquisition, but not in the retrieval, of eyeblink classical conditioning using a trace paradigm. Such a deficit was task-selective, as lesioned rats were able to acquire a fixed-interval operant conditioning as controls, and was not due to nonspecific motor alterations, because spontaneous locomotion and blink reflexes were not disturbed by the MSDB lesion. The deficit in the acquisition of a trace eyeblink classical conditioning was reverted by the systemic administration of carbachol, a nonselective cholinergic muscarinic agonist, but not by lobeline, a nicotinic agonist. These results suggest a key role of muscarinic denervation on the acquisition of new motor abilities using trace classical conditioning procedures. It might also be suggested that muscarinic agents would be useful for the amelioration of some associative learning deficits observed at early stages in patients with Alzheimer's disease.     

Single, but not multiple pairings of sucrose and corticosterone enhance memory for sucrose drinking and amplify remote reward relativity effects

This study tested whether pre-training pairings of ingestion of a 32% sucrose solution and injection(s) of corticosterone (B) would enhance later ingestion in the absence of B, and whether these effects would carry over into later contrast-like effects when animals were subsequently shifted to 4% sucrose. Frequency-dependence of these pairings was also examined. Three groups of male Sprague-Dawley rats were adrenalectomized (ADX). A fourth group was sham ADX. Each ADX group received three presentations of sucrose and B (666 microg/kg, s.c.). One received unpaired presentations (separated by days), one received two unpaired presentations and one paired (i.e., simultaneous) presentation, and one received three paired presentations. Shams received three sucrose presentations paired with saline. Single, but not multiple pairings of B with ingestion of a 32% sucrose solution enhanced later sucrose ingestion, a memorial-like effect that carried over into later, opposite contrast-like effects upon presentation of a less-preferred 4% sucrose solution. These effects could not be easily ascribed to differences in training, other than the pairing regimen itself, nor to motivational differences at the time of testing, and were presumed to be memorial. The pairing and frequency-dependence of these appetitive phenomena are analogous to what is frequently observed during acute or chronic exposure to aversive situations and/or neuromodulatory stress hormones, in terms of their bidirectional effects on memory. Through effects on memory, stress hormones may modulate reward and reward relativity.     

Personality and creativity

Previous research has provided conflicting accounts of the effects of personality on creative behaviour. This study examines the issue by means of factor analysis and multivariate analysis of variance. Different measures of creative behaviour and cognitive abilities are correlated with personal characteristics such as psychoticism, extraversion and other measures of personality. The results are consistent with the idea that different forms of creative behaviour are related to distinct characteristics of personality.