Associations Between Parental Psychopathic Traits,Parenting, and Adolescent Callous-Unemotional Traits

Research on Child and Adolescent Psychopathology - Callous-unemotional (CU) traits (i.e., callousness, low empathy, shallow affect) have been conceptualized as a downward extension of the...     

Youth Appraisals of Inter-parental Conflict and Genetic and Environmental Contributions to Attention-Deficit Hyperactivity Disorder: Examination of GxE Effects in a Twin Sample

Identification of gene x environment interactions (GxE) for attention-deficit hyperactivity disorder (ADHD) is a crucial component to understanding the mechanisms underpinning the disorder, as prior work indicates large genetic influences and numerous environmental risk factors. Building on prior research, children’s appraisals of self-blame were examined as a psychosocial moderator of latent etiological influences on ADHD via biometric twin models, which provide an omnibus test of GxE while managing the potential confound of gene-environment correlation. Participants were 246 twin pairs (total n = 492) ages 6–16 years. ADHD behaviors were assessed via mother report on the Child Behavior Checklist. To assess level of self-blame, each twin completed the Children’s Perception of Inter-parental Conflict scale. Two biometric GxE models were fit to the data. The first model revealed a significant decrease in genetic effects and a significant increase in unique environmental influences on ADHD with increasing levels of self-blame. These results generally persisted even after controlling for confounding effects due to gene-environment correlation in the second model. Results suggest that appraisals of self-blame in relation to inter-parental conflict may act as a key moderator of etiological contributions to ADHD.     

Age differences in genetic and environmental influences on eating attitudes and behaviors in preadolescent and adolescent female twins

A sample of 680 11- and 602 17-year-old female twins was used to examine (a) age differences in genetic and environmental influences on disordered eating attitudes and behaviors and (b) associations between body mass index (BMI) and eating attitudes and behaviors. Univariate, biometrical model-fitting analyses indicated that 11-year-old twins exhibited less genetic and greater shared environmental influence on eating attitudes and behaviors than 17-year-old twins. Bivariate model-fitting analyses indicated that the relationship between BMI and eating attitudes was mediated primarily by common shared environmental influences in 11-year-old twins and common genetic influences in 17-year-old twins. Nonetheless, the majority of genetic influences on eating attitudes and behaviors in older twins were due to genetic effects that are independent of those operating in BMI.     

Genes, personality, and attachment in adults: a multivariate behavioral genetic analysis

Behavioral genetic methods were used to estimate genetic and environmental contributions to (a) attachment-related anxiety and avoidance and (b) the overlap between these attachment dimensions and the Big Five personality traits. Two major findings emerged from these analyses. First, individual differences in attachment-related anxiety and avoidance were heritable, and second, much of the overlap between adult attachment and the Big Five traits was due to shared genetic influences. Discussion focuses on the implications of these results for attachment theory and research and provides a speculative account of the interplay between temperamental dimensions and internal working models of relationships across the life span.     

Auditory perception of conspecific and heterospecific vocalizations in birds: evidence for special processes.

Budgerigars (Melopsittacus undulatus), canaries (Serinus canaria), and zebra finches (Poephila guttata castanotis) were tested for their ability to discriminate among distance calls of each species. For comparison, starlings (Sturnus vulgaris) were tested on the same sounds. Response latencies to detect a change in a repeating background of sound were taken as a measure of the perceptual similarity among calls. All 4 species showed clear evidence of 3 perceptual categories corresponding to the calls of the 3 species. Also, budgerigars, canaries, and zebra finches showed an enhanced ability to discriminate among calls of their own species over the calls of the others. Starlings discriminated more efficiently among canary calls than among budgerigar or zebra finch calls. The results show species differences in discrimination of species-specific acoustic communication signals and provide insight into the nature of specialized perceptual processes.     

Are eating disorders culture-bound syndromes? Implications for conceptualizing their etiology

The authors explore the extent to which eating disorders, specifically anorexia nervosa (AN) and bulimia nervosa (BN), represent culture-bound syndromes and discuss implications for conceptualizing the role genes play in their etiology. The examination is divided into 3 sections: a quantitative meta-analysis of changes in incidence rates since the formal recognition of AN and BN, a qualitative summary of historical evidence of eating disorders before their formal recognition, and an evaluation of the presence of these disorders in non-Western cultures. Findings suggest that BN is a culture-bound syndrome and AN is not. Thus, heritability estimates for BN may show greater variability cross-culturally than heritability estimates for AN, and the genetic bases of these disorders may be associated with differential pathoplasticity.     

Operant methods for mouse psychoacoustics

Tone detection thresholds for a 10-kHz tone in NMRI mice were determined in psychoacoustic experiments using both a constant-stimuli procedure and a two-down/one-up adaptive-tracking procedure in the same subjects and applying identical threshold criteria (70.7% response probability). Constant-stimuli thresholds were on average 24 dB lower than adaptive-tracking thresholds, and there was a trend indicating that constant-stimuli thresholds were less variable than adaptive-tracking thresholds. Furthermore, in the constant-stimuli procedure the number of trials constituting the psychometric function could be reduced from 100 to 50 trials without a large loss of accuracy of threshold determination. In the constant-stimuli procedure, the threshold value was affected by the threshold criteria. The lowest and least variable constant-stimuli thresholds were obtained by applying signal detection theory and a criterion ofd′=1. Thus, the constant-stimuli procedure in combination with signal detection theory appears to be better suited than the adaptive-tracking procedure to determine auditory sensory thresholds.