Read about the latest research published in Clinical Psychological Science:
Frank D. Mann, Jennifer L. Tackett, Elliot M. Tucker-Drob, and K. Paige Harden
Past research has identified a gene × trait interaction in which conduct problems are more heritable in the presence of high levels of callous-unemotional (CU) traits than in the presence of low CU traits. The current study replicated and extended these findings by measuring CU traits, aggression, and rule breaking in monozygotic and dizygotic twins who were part of the Texas Twin Project. The researchers found that the heritability of aggression was higher in adolescents with high levels of CU traits than in those with low levels of CU traits. In addition, environmental influences on rule-breaking were found to follow the same pattern. These findings suggest that aggression and nonaggressive rule-breaking have distinct etiologies.
Erin K. Moran and Ann M. Kring
Past research has shown that in the presence of positive stimuli, both people with schizophrenia and people without it display comparable neural and physiological responses. Schizophrenia has also been linked to anhedonia, the diminished experience of pleasure, and one explanation for this is a deficit in anticipating evocative stimuli. The present study examined differences in experiences of emotion while anticipating future positive and negative stimuli in people with and without schizophrenia. Participants were shown positive, neutral, and negative pictures from the International Affective Picture System (IAPS) in two different tasks. In the first task, participants viewed cues (i.e., + for positive, – for negative, O for neutral) on a screen indicating the valence of the subsequent picture, rated their valence and arousal on a pictorial assessment, and then viewed an IAPS picture. Startle probes were presented during the anticipatory period, picture presentation, or during the intertrial intervals. In the second task, participants were shown the same IAPS pictures and asked to rate their valance and arousal while viewing the pictures. They found that people with schizophrenia failed to exhibit valence-modulated blink responses to anticipated evocative pictures, suggesting a dampened anticipatory emotional response.
Keith Bredemeier, Aaron T. Beck, and Paul M. Grant
Research has suggested a link between reduced cognitive insight and neurocognitive impairment in those with schizophrenia. However, the studies providing this evidence have been cross-sectional in nature; longitudinal research is needed to examine the causal link between these two factors. The researchers examined the temporal order of reduced cognitive insight and neurocognitive impairment in participants with schizophrenia or schizoaffective disorder using two longitudinal samples (a naturalistic study of adult outpatients and a sample from a randomized treatment trial). Participants were assessed for neurocognitive performance and cognitive insight at baseline and at a 6-month follow-up assessment (Study 1) or at baseline and at 6-, 12-, 18-, and 24-month follow-up assessments (Study 2). Cognitive insight measured at baseline (Study 1) and at the end of treatment at 18 months (Study 2) was found to prospectively predict neurocognitive performance at 6 months (Study 1) and 24 months (Study 2). The reverse relationship (from neurocognitive performance to cognitive insight) was not supported in either study.
Frances L. Wang and Laurie Chassin
Serotonin functioning in the brain has been associated with problematic alcohol consumption; however, the mechanisms that underlie this association remain unclear. Impulsive reactivity to emotions (the tendency to act impulsively when confronted with positive or negative emotions) has been proposed as one potential mechanism. The data for this study were collected as part of a multigenerational longitudinal study on familial alcoholism. The overarching longitudinal study began by following adolescents (G2) and their parents (G1). As the G2 adolescents aged into adulthood, they themselves became parents. Their children (G3), who were in early or late adolescence, were the primary focus of the current study. In this study, parents (G2) reported their level of education, their own lifetime drug and alcohol use/dependence, and their children’s (G3) prescription medication use. Genetic samples were also obtained and a polygenic score was formed indexing serotonin functioning. Over the following 4 years, G3 participants were assessed, at various time points, for alcohol problems and five facets of impulsivity (i.e., negative urgency, positive urgency, lack of premeditation, lack of perseverance, and sensation seeking). Negative urgency — but no other facet of impulsivity — mediated the relationship between serotonin polygenic score and alcohol problems.