Pavlov's position on the effects of decortication on conditional reflexes.

This paper examined D. Joravsky's (1989) hypothesis that I.P. Pavlov dogmatically refused to acknowledge that classical conditioning can be mediated by subcortical regions of the large cerebral hemispheres. Decortication literature from 1901 to 1936 was reviewed. The early studies available to Pavlov, who died in 1936, showed that decortication does not allow the establishment of new or retaining of old conditional reflexes (CRs). G.P. Zeleny?'s later experiments(1930) suggested that the establishment of primitive CRs in decorticated dogs was possible. Pavlov never denied this possibility but cautioned that Zeleny?'s experiments could have been methodologically flawed. Although Joravsky's original hypothesis on Pavlov's position on the relation between decortication and the establishment of CRs is by and large accepted, it must be stressed that Pavlov's theory of higher nervous activity was primarily concerned with the function of the brain in the higher organism's struggle for existence. Within this context the cortical, rather than subcortical, processes play the decisive role in the organism's adaptation to the changing external environment.     

The twisted helix: An essay on genetic counselors,eugenics, and social responsibility

The American eugenics movement had a significant impact on American social history, and analysis of the movement illustrates the relationship among science, scientists, and society. The history of the American eugenics movement as well as more recent examples of eugenic thought and biological determinism are reviewed. The need for genetic counselors to confront eugenic issues in their own profession and in society is discussed.     

Developmental sequences in the age of onset of disruptive child behaviors

Retrospective and prospective reports of the onset of disruptive child behaviors were analyzed in a sample of clinic-referred boys. The younger boys (ages 7–9 years), compared with the older boys (ages 10–12 years), showed the highest level of disruptive behavior and, judging from mothers' reports, had the fastest progression of onsets from less serious to more serious problem behaviors. Despite some overlap, developmental sequences in problem behavior within the domains of hyperactivity/inattention, oppositional behavior, and conduct problems were similar across the two age groups. This was also the case for developmental sequences of overt or confrontive problem behaviors and covert or concealing conduct problems. Sequences of the onset of oppositional behavior and conduct problems were validated through prospective data, based on the information from mothers, teachers, and boys themselves. The implications of the findings are discussed for the formulation of developmental pathways of behavior and the analysis of causal factors.     

Assessing the acceptability of staff management procedures to direct care and supervisory staff

Direct care and supervisory staff in five residential training programs for persons with mental retardation in North Dakota rated the acceptability of six staff management procedures. Overall, staff rated “Instructions”, “Instructions and Modeling”, “Feedback and Praise”, and “Instructions, Feedback, and Praise”, as significantly more acceptable than “Self-Management” and “Self-Management, Feedback and Praise”. There was a significant group by treatment interaction in which supervisors and direct care staff had significantly different acceptability rating for four of the six procedures. The results were further analyzed by group and implications and future research are discuessed.     

Parallel discrimination of subjective contours defined by offset gratings

Recent physiological studies (von der Heydt & Peterhans, 1989) suggest that the orientation of subjective contours is encoded very early in the visual system (V2 in monkey). This result is seemingly at odds with existing psychophysical data which suggest that the detection of subjective contours involves selective attention. It is argued that certain subjective contours are registered in a reflexive (bottom-up) manner by the visual system but that selective attention may be needed to gain access to this representation. To assess this suggestion, a visual-search task was used in which subjects were to detect the presence of a horizontal (vertical) subjective contour (defined by offset gratings) in a variable number of vertical (horizontal) subjective contours (also defined by offset gratings). When there were no competing organizations within the display, detection was indeed independent of the number of nontarget distractors, that is, selective attention was unnecessary. In a second experiment, we found that a curved form (a crescent defined by subjective contours) was easier to detect in a background of vertical bars (also defined by subjective contours) than vice versa, namely, a search asymmetry paralleling those found by Treisman and Gormican (1988). A final experiment showed that when the horizontal and vertical bars of the first experiment formed textured regions, they could be discriminated at very brief display durations (30–120 msec), However, when the line terminations aligned along the subjective contour were tapered rather than abrupt, discrimination dropped off with the degree of tapering. The latter result is consistent with the assumption that the registration of subjective contours in V2 involves the integration of responses from aligned, end-stopped cells found in VI (von der Heydt & Peterhans, 1989).     

The role of physical attractiveness in adjustment.

This article presents a model of how attractiveness influences adjustment and reviews the relevant evidence. The model suggests that attractiveness influences adjustment through a three-stage process. Varying levels of physical attractiveness create differential responses in other people (Stage 1). These differential responses in others as a function of a person's appearance then result in differential treatment of the person (Stage 2), with such differential treatment eventually resulting in differential adjustment (Stage 3). These three stages are considered to occur in a reciprocal manner across the life span. Empirical support is found for each stage from early childhood to adulthood. Attractiveness accounts for 6% to 16% of the variance in measures of subjective adjustment as well as sociometric and behavioral measures of interpersonal adjustment.     

Repeated failure: a source of helplessness or a factor irrelevant to its emergence?

We tested the validity of the egotism model of human helplessness. In contrast to the original theoretical approach of Seligman and his associates, which points to response-outcome noncontingency as the main source of helplessness, the egotism alternative proposes that repeated failure itself is the critical determinant of helplessness symptoms. Repeated failure threatens the self-esteem of the subject, who supposedly engages in a least-effort strategy during the test phase of a typical learned helplessness study, which results in performance impairment. To examine the egotism explanation, we gave subjects noncontingent-feedback training with or without repeated failure on five consecutive discrimination problems. In two experiments, noncontingent-feedback preexposure produced helplessness deficits in performance on avoidance learning, whereas repeated failure appeared irrelevant to helplessness. This and our other findings from research are inconsistent with the egotism explanation and support instead Seligman's original proposal, in which helplessness is attributed to prolonged experience with noncontingency.     

Attenuation of amphetamine-stereotypy by mesostriatal dopamine depletion enhances plasma corticosterone: implications for stereotypy as a coping response

The relationship between amphetamine-induced stereotyped behavior and a neuroendocrine index of arousal, plasma corticosterone (CCS), was investigated. 6-Hydroxydopamine lesions of the caudate-putamen, which produced dopamine depletions of 60%, blocked stereotypy and prolonged the elevation in corticosterone associated with d-amphetamine treatment (5 mg/kg). Similar dopamine depleting lesions of the nucleus accumbens, which attenuated the locomotor, but not the stereotypic, response to AMPH did not have this effect on CCS. This pattern of results supports the hypothesis that stereotypy has a coping function which may serve to alter arousal and further suggests important differences between the nigrostriatal and mesolimbic dopamine projections in modulating the responsiveness of the neuroendocrine system. These results have implications for understanding the function of behavioral stereotypies common to a number of psychopathological conditions, including schizophrenia and childhood autism.     

A flavor paired with lithium chloride blocks the formation of a pentobarbital-lithium chloride association

Thirsty rats were used in order to determine whether a vinegar solution, which had been paired with an injection of lithium chloride, could block the formation of an association between a pentobarbital- and a lithium chloride-induced state. During phase 1 the rats in the blocking group had a 2.0% vinegar solution paired with an injection of 240 mg/kg of lithium chloride, during phase 2 these rats were reexposed to the vinegar prior to each injection of 20 mg/kg of pentobarbital and 240 mg/kg of lithium chloride, and during phase 3 these rats were given access to a novel 0.75% saccharin solution and were injected with pentobarbital after saccharin removal. Animals with this history did not form an association between the pentobarbital- and lithium chloride-induced states during phase 2 as evidenced by their refusal to consume the saccharin solution over repeated pairings of saccharin with pentobarbital during phase 3. Control groups that received forward pairings of pentobarbital and lithium chloride, in the absence of a previously conditioned vinegar solution during phase 2, formed an association between pentobarbital and lithium chloride. These findings indicate that drug states and flavors can interfere with each others' capacity to predict the occurrence of lithium chloride.     

Relation of cognitive operational performance to comprehension and production of dimensional adjectives

This study compared normal developing children, aged 34 to 51 mo., on comprehension and production of relative dimensional adjectives using object manipulations in a close elicitation procedure and on Piagetian operational tests of conservation of continuous quantity, length, reversibility and seriation. Analysis indicated a significant difference on the expressive language performance of the transitional and the concrete operational children over the preoperational children, but no significant differences occurred between the first two groups. Children who performed better on seriation were significantly better on expressive language performance. Children classified as operational for length performed better on all language measures than those classified as nonoperational. Reversibility and conservation of a continuous quantity did not differentiate children.