Organism-environment mutuality epistemics,and the concept of an ecological niche

The concept of an ecological niche (econiche) has been used in a variety of ways, some of which are incompatible with a relational or functional interpretation of the term. This essay seeks to standardize usage by limiting the concept to functional relations between organisms and their surroundings, and to revise the concept to include epistemic relations. For most organisms, epistemics are a vital aspect of their functional relationships to their surroundings and, hence, a major determinant of their econiche. Rejecting the traditional dualism of organism and environment, an econiche is defined as the reciprocal (dual) of a functionally specified class of organisms (FSTU). From this perspective, an econiche necessarily implies a certain type of organism, and a class of functionally similar organisms implies a special econiche.The econiche concept is also discussed in relation to other ecological terms that reflect the distributional patterns of organisms, such as habitat, and the concept of an empty niche is criticized.Special thanks are due to Michael Turvery for his part in many stimulating discussions of some of the problems and concepts addressed in this paper. I am also grateful to him and to Claudia Carello, Tim Johnston, Bill Mace, Bernard Patten, Ed Reed, Robert E. Shaw, Bill Warren, and an anonymous reviewer for their comments on earlier drafts of this paper.     

Social categorization,visual cues,and social judgements

Recent research on social cognition suggests that lifelike visual and vocal information about a person may strongly mediate the impact of prior social categorical knowledge on social judgements. Other research, however, on the contribution of visual cues to impression formation, suggests that they have relatively little impact. This study sought to resolve these conflicting findings by examining the effect of visual cues on social judgements when subjects possess prior social categorical knowledge varying in salience to the experimental task. Videotaped target interviews were monitored by observers in either sound and vision or sound only, and measures were taken of the targets' perceived personality, their ‘actual’ and ‘predicted’ social performance, and social acceptance by observers. Whilst salience of categorization strongly influenced the quality of judgements, visual cues had little if any effect. However, visual cues strongly influenced subjects' confidence in all three sets of judgements, sound and vision subjects being consistently more confident than their sound only counterparts. The findings are discussed in relation to previous research in both social cognition and visual cues.     

Nonprofessional counselors: Revisiting selection and impact issues

This study examined two issues related to the use of nonprofessional counselors (n = 159) within the context of a diversion program for juvenile offenders. First, the relationship of the nonprofessionals' personality traits and general attitudes to client outcome was examined. No statistically significant correlations were observed. Second, the differential impact of various training and supervision factors was examined in terms of nonprofessional satisfaction, attitudes, and locus of control. Results suggested that training intensity, training content, and supervision setting may influence nonprofessionals' attitudes towards various social groups and their satisfaction with the nonprofessional experience.     

Adaptation and vulnerability in high-risk adolescents: An examination of environmental mediators

The relationship of characteristics of the social environment to the adaptation of adolescents from high-risk predisposing environments was examined. Specifically, the degree to which adolescents' perceptions of various dimensions of their family and school environment as well as sources of social support related to differential levels of personal well-being and academic adjustment was explored. Multiple regression analyses revealed differences in the salience of the dimensions of the social environment as a function of the particular sphere of functioning under consideration. Implications of the findings for developing a model for understanding the relative vulnerability of individuals at risk as well as of the design of preventive interventions are discussed.     

Continuous monitoring of human contingency judgment across trials

Recent evidence suggests that people are sensitive to the degree of contingency between their actions and ensuing outcomes, but little is known about the way in which such contingency judgments develop as more and more information about the contingency is provided. Three experiments examined this issue in the context of a video game. In Experiment 1, it was found that contingency judgments follow growth functions: When the contingency was positive, judgments increased toward a positive asymptote, and when the contingency was negative, judgments decreased toward a negative asymptote. When the contingency was zero, judgments themselves remained close to zero but were biased by the overall frequency with which the outcome occurred. In Experiment 2, it was shown that the growth function was not the result of the anchoring of early judgments at the zero point. The bias in judgments when the contingency is zero was investigated in Experiment 3. The results are discussed in terms of rule-based analyses and contemporary theories of conditioning.     

Recent stressful life events and young children's school adjustment

A group of 211 first-to fourth-grade children who had experienced one or more recent stressful life events were compared to a demographically matched sample of 211 children who had not experienced such events on measures of school adjustment problems and competencies. Stressful life events were found to be associated with the presence of more serious school adjustment problems and fewer competencies. Those associations were strongest for children who had experienced multiple recent stressful events. The importance of preventive interventions for this at-risk group was emphasized and future research steps in the area were considered.     

Selective association in conditioned stress-induced analgesia: functional differences in interoceptive and exteroceptive sensory pathways

Rats were used to determine whether stress-induced analgesia (SIA) can be produced by conditioning with interoceptive stimuli (LiCl) as with exteroceptive stimuli (footshock). SIA was measured using a tail-flick test. As expected, unavoidable footshock as well as conditioning with footshock produced SIA. In contrast, conditioning with LiCl failed to cause SIA. The findings support the notion of functional differences in neural substrates for conditioning by exteroceptive and interoceptive cue.     

Suppression of corticosterone synthesis alters the behavior of hippocampally lesioned rats

The suppression of corticosterone synthesis with metyrapone (25 mg/kg) reduced the hyperactivity and altered the exploratory activity of hippocampally lesioned animals (HPC) in the open field to the level of cortical and sham controls (Experiment 1). In a second experiment, corticosterone (600 micrograms/kg) pretreatment 2 h, but not 1 h, before metyrapone partially restored the hyperactivity of HPC animals that had been decreased by the corticosteroid-suppressant drug. Alterations in exploratory behavior induced by metyrapone were also prevented by corticosterone pretreatment. The results suggest that the suppression of corticosterone in hippocampally lesioned animals produces a normalization of behavior that can be prevented by pretreatment with corticosterone.     

Effects of social isolation in adulthood on odor preferences and urine-marking in male rats

Male rats isolated for 60 days in adulthood spent less time investigating odors of females and urine-marked less over these odors than did males kept in groups of three. Isolated males did not differ from grouped males in their responses to odors of unfamiliar males or their own odors. After social experience the isolated males showed an increase in urine-marking but no change in odor preferences. Individual housing therefore appears to alter olfactory communication in the same way that it does other social behaviors and these changes may be mediated by the same mechanisms.