Q-sort assessment of attachment security during the preschool years: links from home to school

This study investigated relations among preschoolers' secure-base behavior with mother at home, stressful family conditions, and qualities of developing relationships with peers and teachers in preschool. Preschool-age children (N = 94; 51 boys and 43 girls) and their mothers were observed during multiple home visits, and their security of attachment was assessed with the Attachment Q-Set. Children in families with lower levels of stress had more secure attachment relationships with mothers. Both boys and girls who were less securely attached to their mothers expressed significantly more anger-aggression in preschool. For boys, higher levels of family stress were also significantly related to anger-aggression and to social competence in preschool. In addition, boys who were more securely attached to their mothers were more securely attached to their preschool teachers and were more popular with peers in preschool.     

Now you see it, now you don't: explicit versus implicit measures of the personal/group discrimination discrepancy

When making explicit self-report ratings, members of status- and racial-minority groups report less personal experience with discrimination than that encountered by their group—a phenomenon called the personal/group discrimination discrepancy (PGDD). This study provides evidence, for the first time, that the PGDD may be, in part, a product of the procedure used to measure it. White women and men completed explicit and implicit measures of personal and group discrimination based on sex. The PGDD surfaced among women in the explicit measures, but not in the implicit measures. These findings suggest that explicit and implicit measures might provide different assessments of experience with discrimination.     

Nonconscious priming after 17 years: invulnerable implicit memory?

Individuals who saw pictures for 1 to 3 s in the laboratory were tested 17 years later by mail. Identification rates were significantly higher for fragments from these previously exposed targets than for novel fragments, whereas the same stimuli evoked no differences in control groups that had not been previously exposed to the pictures. Priming--the memorial advantage conferred by prior perceptual experience--was stable over the years (r= .51). Priming was dissociated from episodic memory, in that it was present even in subjects who reported no conscious recollection of their participation in the original laboratory session. These findings suggest that the perceptual representation system is an invulnerable memory system functioning below conscious awareness.     

HIV-1 encephalopathy among perinatally infected children: Neuropathogenesis and response to highly active antiretroviral therapy

HIV-1 encephalopathy among perinatally infected children in the United States was initially defined by a classic triad of findings that included: (1) developmental delay, (2) secondary or acquired microcephaly, and (3) pyramidal tract neuromotor deficits. The most severe form of this disorder typically occurred among young children who developed rapidly progressive disease in concert with profound immunosuppression, and Pneumocystis jiroveci pneumonitis (PCP). The neuropathogenesis of this disorder appears to involve a cascade of viral products, various cytokines and chemokines, and neurotransmitters which promote ongoing inflammation, excitation, and overstimualtion of the N-methyl-D-aspartate type receptor (NMDAR) system. These subsequently lead to neuronal injury and death secondary to apoptosis or necrosis, astrocytosis, as well as dentritic and synaptic damage. The frequency of the most severe forms of encephalopathy among children has dropped dramatically since the introduction of highly active antiretroviral therapy (HAART). Of concern, however, is the possibility that a more insidious form of this disorder may be occurring presently among older vertically infected children as a result of inadequate penetration of HAART agents into the cerebrospinal fluid (CSF). This paper will review what published data there is as yet that bears on this question.     

Lateral and anterior thalamic lesions impair independent memory systems

Damage to the medial region of the thalamus, both in clinical cases (e.g., patients with infarcts or the Korsakoff's syndrome) and animal lesion models, is associated with variable amnesic deficits. Some studies suggest that many of these memory deficits rely on the presence of lateral thalamic lesions (LT) that include the intralaminar nuclei, presumably by altering normal function between the striatum and frontal cortex. Other studies suggest that the anterior thalamic nuclei (AT) may be more critical, as a result of disruption to an extended hippocampal system. Here, highly selective LT and AT lesions were made to test the prediction that these two regions contribute to two different memory systems. Only LT lesions produced deficits on a preoperatively acquired response-related (egocentric) working memory task, tested in a cross-maze. Conversely, only AT lesions impaired postoperative acquisition of spatial working memory, tested in a radial maze. These findings provide the first direct evidence of a double dissociation between the LT and AT neural aggregates. As the lateral and the anterior medial thalamus influence parallel independent memory processing systems, they may each contribute to memory deficits, depending on lesion extent in clinical and experimental cases of thalamic amnesia.     

Dopamine D2 receptors mediate reversal learning in male C57BL/6J mice

Dopamine is critical for directing goal-oriented behavior. We investigated dopamine D₂ receptor involvement in reversal learning and reinforcement efficacy in mice lacking functional dopamine D₂ receptors and their heterozygous and wild-type littermates. Mice discriminated between two odors to receive a food reinforcer: One odor signaled a reinforcer (S⁺); the other odor signaled no reinforcer (S⁻). After mice learned the S⁺/S⁻ relationship, we inverted the reinforcement contingencies. The necessary number of trials to relearn the new reinforcement contingencies served as our index of reversal learning. Mice lacking functional dopamine D₂ receptors repeatedly failed to inhibit previously reinforced responses during reversal trials. In a separate experiment, mice responded for reinforcers on a progressive ratio schedule of reinforcement. Mice lacking functional dopamine D₂ receptors earned significantly fewer reinforcers than did heterozygous mice. Our results suggest that dopamine D₂ receptors regulate reversal learning and influence the reinforcing efficacy of natural rewards.     

Inferences about the authentic self: when do actions say more than mental states?

Three studies involving 478 undergraduates examined the perceived importance of observable actions versus mental states in revealing the "true self"-the authentic and fundamental nature of a target person. Results suggest that when people have only limited information about a target, they believe that an action is more diagnostic of the individual's true self than the accompanying mental state. When participants have knowledge concerning chronic dispositional tendencies of the target, however, they judge that a chronic mental state is more diagnostic of the true self than a chronic action tendency. Considered together, the findings suggest that people conceptualize the true self as a relatively private entity but nevertheless believe that an action of a little-known person may be particularly informative about that individual. Perceived diagnosticity of the true self was partially mediated by inferences concerning the relative stability of actions versus states but not by inferences of volition.     

Test-retest reliability in performance of persons with hemiparesis tracking by means of compatibly displayed myoelectric feedback derived from upper limb muscles

The aim of this study was to assess whether persons with hemiparesis will yield statistically reliable test-retest tracking performance on a procedure using limb-generated, compatibly displayed, myoelectric video feedback. A convenience sample of 50 inpatients and outpatients with upper extremity involvement of at least six months were recruited. 30 had hemiparesis and had both upper extremities tested. 20 had hemiplegia and had the nonparetic upper extremity tested. Tracking skill was measured as mean tracking error. Repeated measures analysis of variance yielded statistically significant effects of main factors: Response mode, Cursor Feedback, and Session. Extremity tested was not significant. Performance with involved limb, uninvolved limb, isometric mode, and isotonic mode all yielded positive rest-retest correlations. The reliable range of tracking error obtained from subjects with hemiparesis performing a task requiring modulation of compatibly displayed myoelectric output supports the therapeutic rationale for employing compatibly displayed video feedback in the rehabilitation of motor control.     

Cognitive style and plebe turnover at the U.S. Naval Academy

Students entering (N = 1,134) the U.S. Naval Academy class of 2000 were administered the Kirton Adaption-Innovation Inventory on the first day of Plebe Summer, a 7-wk. nonacademic training program completed by all entering students in the summer prior to the freshman year. The mean score on Innovation cognitive style for this sample of plebes was approximately a standard deviation lower than those of five other undergraduate student samples from nonmilitary universities. Furthermore, the 98 plebes who voluntarily withdrew before completing the program scored higher on the average on Innovation than those who remained. Findings suggest that, in terms of Person-Organization fit, plebes with a more innovative cognitive style may, perhaps, be less compatible with the regimentation-style climate of the Academy than those with an Adaptive cognitive style. Further research, however, is needed to specify the relationship between Academy students' cognitive style and other important organizational outcomes.