Establishing a relationship between activity reduction in human perirhinal cortex and priming.

Perirhinal neurons exhibit reduced firing rates with stimulus repetition, a phenomenon termed "repetition suppression." However, relationships between perirhinal repetition suppression and behavioral expressions of memory remain unclear. We used anatomically constrained functional magnetic resonance imaging (fMRI) to assess relationships between perirhinal activity and priming, a type of implicit memory. Priming was expressed as speeded animacy judgments for old versus new words. Concurrently, old words elicited less neural activity in bilateral perirhinal cortex. The magnitude of the left perirhinal activity reduction selectively predicted the magnitude of behavioral priming in an across-subjects hierarchical linear regression analysis. These findings have implications for considering how perirhinal cortex may contribute to different neurocognitive functions, possibly including both implicit memory and familiarity-based recognition. This study documents the first evidence linking behavioral measures of priming to information processing in perirhinal cortex.

An Examination of Content Overlap and Disorder-Specific Predictions in the Associations of Neuroticism with Anxiety and Depression.

This study examines whether content overlap artificially inflates estimates of the associations of emotional disorders with neuroticism and whether disorder-specificity of prediction exists. We demonstrated a statistical approach for testing the validity of hypothesized facets of neuroticism. In a sample of 627 adolescents, we indentified six facets of neuroticism, one intermediate facet, and a general neuroticism factor (GNF). Only the GNF and the depression facet were significantly associated with depressive symptomatology. The GNF and all facets significantly predicted anxiety symptomatology. This study offers a new statistical approach for addressing content overlap, testing for disorder specific prediction and identifying facets of a broad personality trait, while indicating that content overlap does not largely explain the associations of neuroticism with psychopathology.

Neuroticism and introversion are associated with salivary cortisol patterns in adolescents.

Previous studies have yielded equivocal findings on the relationship between personality and cortisol activity. The present study examined associations between personality and cortisol activity in a large, diverse adolescent sample, while partialling the effects of relevant demographic and health-related covariates. A subsample of 230 participants (57% of whom reported elevated neuroticism) was selected from a larger sample of 16-18-year olds involved in a study on risk factors for emotional disorders. Subsample participants completed a battery of personality questionnaires, and saliva collection was requested several months later on three consecutive days at six time points per day, from wakeup to bedtime. Associations between personality and cortisol rhythms were examined using multilevel growth curve modeling. Neuroticism (N) and introversion (I) were significantly and differentially associated with features of diurnal cortisol patterns. Specifically, a significant N x gender interaction was observed, demonstrating flatter cortisol rhythms across the waking day among male participants with higher N. Elevated I, however, was associated with lower cortisol awakening responses for both male and female participants, and higher cortisol at the time of waking for male participants only. The present study supports personality as a significant predictor of diurnal cortisol patterns in late adolescence, after accounting for the effects of demographic and health covariates, and suggests that gender plays a role in moderating associations between personality and cortisol.

A subtype of speech delay associated with developmental psychosocial involvement.

This report presents findings supporting the hypothesis of a clinically relevant subtype of childhood speech sound disorder, provisionally titled speech delay-developmental psychosocial involvement (SD-DPI). Conversational speech samples from 29 children who met inclusionary criteria for SD-DPI were selected from a case record archive at a university speech clinic for children. Participants with SD-DPI had been characterized by speech clinicians and caregivers as having speech delay with psychosocial issues that required attention in the course of at least 1 semester of speech treatment. The 29 participants were divided into 2 subgroups, based on clinicians' and parents' records indicating either approach-related negative affect (n = 23) or withdrawal-related negative affect (n = 6). Each participant with SD-DPI was matched by age, gender, and type of speech involvement to 3 comparison speakers with speech delay of unknown origin (n = 87). Analyses of the conversational speech samples indicated that in comparison with participants in the control group, those with SD-DPI had significantly more severe speech delay, averaging approximately 7% to 10% lowered speech competence in conversation. The clinical prevalence of SD-DPI was estimated at approximately 12% of children referred to the university speech clinic in the present study. The authors interpret the present findings to indicate that approach-related or withdrawal-related negative affect, negative emotionality or mood, and decreased task persistence or attention are risk factors for increased severity of expression of speech delay.