Overt responding in computer-based training

This experiment compared the extent to which students learned facts included in computer-based-training frames that required an overt response to those that did not. Frames included two types of facts: Some facts had one word missing which had to be supplied by the student (active facts). Other facts had no missing words and required no overt response (passive facts). Each student completed four 14-fact modules in random order. Two of the modules contained frames with all active facts. Each frame in the other two modules contained one active and six passive facts. Paper pretests and posttests showed that students learned twice as many facts when all facts in the module were active than when only one in seven were active. The modules that included passive facts required one-fifth the time to complete than those with only active facts. Students learned more facts per minute of training in one of the two modules that included passive facts than in the two modules with only active facts.     

Isoluminance and contingent color aftereffects

In the typical induction of the orientation-contingent color aftereffect (CCAE), the stimuli are composed of elements that differ in both color and luminance. Three experiments are reported that show that chromatic contrast between stimulus elements is insufficient for the induction of the orientation-CCAE and that luminance contrast is necessary. These experiments expand on previous research concerned with the role of luminance contrast in the induction of orientation-CCAEs by eliminating alternative explanations.     

Aesthetic preference and DSM-IIIR personality disorders

This report tested whether those individuals with a cluster B DSM-IIIR personality disorder (narcissistic, borderline, antisocial or histrionic) had higher scores for aesthetic preference for visually complex drawings using the Barron-Welch Art Scale. In a sample of 141 patients and controls, the 56 subjects who met the criteria for one of the cluster B personality disorder diagnoses displayed higher Barron-Welch Art Scale Scores. A multiple regression analysis showed that narcissistic and borderline personality disorder contributed positively, while dependent personality disorder, negatively to preference for complexity. The findings support the notion that aesthetic choices and values reflected through the dimension of openness to experience may contribute to the behavioral manifestations of the personality disorders.     

Features Resembling Tourette''s Syndrome in Developmental Stutterers

Developmental stuttering (DS) may be related to the extrapyramidal motor system and shares many clinical similarities with Tourette's syndrome (TS), which is widely believed to be associated with extrapyramidal dysfunction. Twenty-two stutterers were examined for neuropsychiatric features commonly seen in TS, including tics, obsessive-compulsive behaviors (OCB), and attention deficit disorders. Eleven stutterers displayed motor tics, and symptoms of OCB were observed at rates similar to those seen in persons with TS. Few stutterers demonstrated significant attentional deficits. Findings are consistent with models suggesting extrapyramidal involvement in DS and raise the possibility that DS and TS are pathogenetically related.     

An Ecologically Differentiated, Multifactor Model of Adolescent Network Orientation

The paper presents a test of an ecologically differentiated model of social network orientation for adolescents that distinguished between different social network reference groups (family, peers, and nonfamily adults). The model was tested in two consecutive studies. Study 1 describes initial model development (N = 120). Study 2 presents a confirmatory factor analysis with a second sample (N = 430) to replicate the factor structure developed in Study 1. Results supported a three-factor model of network orientation that differentiated between network reference groups. Analyses of concurrent and predictive validity indicated that orientation to network reference groups was differentially related to the perceived quality and frequency of support from members of respective social network groups. Group differences (gender, race) regarding network orientation to different network reference groups were consistent with studies of other social network processes. Implications for the study of the network orientation and the study of social networks more generally are discussed.     

Prepulse effects on magnitude estimation of startle-eliciting stimuli and startle responses

The present studies investigated the relationship between prepulse effects on the modification of the brainstem startle reflex and magnitude estimates of startle-eliciting stimuli. In Experiment 1, startle eyeblink responses were elicited in 24 students, half of whom were instructed to estimate the loudness of the startle stimulus (actual intensities of 80, 90, and 100 dB) and half of whom were instructed to estimate the magnitude of their eyeblink. When weak acoustic prepulses preceded the startle-eliciting stimulus, eyeblink amplitude was inhibited, and estimates of response magnitude decreased, but estimates of startle stimulus magnitude decreased only when 100-dB startle stimuli were presented. In Experiment 2, the same startle stimuli were preceded on some trials by a vibrotactile prepulse to the hand. In conditions in which startle amplitude was inhibited, startle stimulus magnitude estimates were not affected. This suggests that the effect of acoustic prepulses on 100-dB startle stimuli in Experiment 1 may have been due to loudness assimilation, an effect independent of the prepulse inhibition of startle responding.     

Maternal stress and pituitary-adrenal manipulations during pregnancy in rats: effects on morphology and sexual behavior of male offspring.

The purpose of the present study was to determine whether the demasculinizing and feminizing effects of prenatal stress (i.e., stress applied to the mother during pregnancy) in rats reported previously are mediated by activation of the maternal pituitary-adrenal axis. Neither whole-body restraint, with or without hyperthermia, nor ACTH treatment during the last third of gestation had any reliable effect on masculine or feminine sexual behavior in male Sprague-Dawley offspring, although these treatments produced maternal pathology and evidence of maternal adrenocorticoid release. Significant littermate similarity was found for almost every morphological and behavioral measure. Failure to control for the litter variable may account for many previously reported effects of prenatal stress on sexual behavior in rats. The discrepancy between the present and earlier findings is discussed in terms of methodological and theoretical considerations.     

Isolating causal effects through experimental changes in parent-child interaction

A distinction is made between functionaland intentionalcontrol in parent-child interaction. These concepts are drawn, respectively, from opérant and cognitive models of interaction process. Experimental evidence is presented that cognitive factors such as expectations or hypotheses indeed affect the relations between parents and their own children. This necessitates a further distinction between long-termand short-termcausal effects: Since changes in parents' expectations for their children may lag behind actual changes in children's behavior, short-term effects inferred from observations of ongoing interactions may not reflect the long-term dynamics of the relationship.