Stability of mood states and biochemistry across pregnancy

Four hundred and thirty pregnant women were recruited during their second trimester of pregnancy (M=20 weeks). They were designated depressed (N=172) or nondepressed (N=258) on the Structured Clinical Interview of Depression (SCID) and the Center for Epidemiological Studies Depression scale (CES-D). They were given a second assessment when they were approximately 32 weeks gestational age. At both assessments they were given self-report measures (CES-D, the State Anxiety Inventory, and the State Anger Inventory) and provided urine samples for assays of cortisol, catecholamines (norepinephrine, epinephrine and dopamine) and serotonin. They were also given the VITAS scale for lower back pain and leg pain and a sleep disturbance scale. The stability of mood states and biochemistry across pregnancy (20 and 32 weeks) were assessed inasmuch as mood states, and biochemistry have been noted to predict prematurity and low birthweight. Significant correlations were noted for all variables except serotonin. Relationships between mood states and biochemistry were also noted but only between cortisol and depression, cortisol and anxiety, and epinephrine and anxiety. Significant stability was noted between the 20-week measures and the 32-week measures including depression, anxiety, anger, and cortisol. These were, in turn, correlated with each other and with, low back pain, leg pain, and sleep disturbance. These data suggest the stability of mood states and cortisol across pregnancy.     

Sleep and the time course of motor skill learning

Growing evidence suggests that sleep plays an important role in the process of procedural learning. Most recently, sleep has been implicated in the continued development of motor-skill learning following initial acquisition. However, the temporal evolution of motor learning before and after sleep, the effects of different training regimens, and the long-term development of motor learning across multiple nights of sleep remain unknown. Here, we report data for subjects trained and retested on a sequential finger-tapping task across multiple days. The findings demonstrate firstly that following initial training, small practice-dependent improvements are possible before, but not following the large practice-independent gains that develop across a night of sleep. Secondly, doubling the quantity of initial training does not alter the amount of subsequent sleep-dependent learning that develops overnight. Thirdly, the amount of sleep-dependent learning does not correlate with the amount of practice-dependent learning achieved during training, suggesting the existence of two discrete motor-learning processes. Finally, whereas the majority of sleep-dependent motor-skill learning develops during the first night of sleep following training, additional nights of sleep still offer continued improvements.     

Examining the Factor Structure of the Self-Compassion Scale in Four Distinct Populations: Is the Use of a Total Scale Score Justified?

This study examined the factor structure of the Self-Compassion Scale (SCS) using a bifactor model, a higher order model, a 6-factor correlated model, a 2-factor correlated model, and a 1-factor model in 4 distinct populations: college undergraduates (N = 222), community adults (N = 1,394), individuals practicing Buddhist meditation (N = 215), and a clinical sample of individuals with a history of recurrent depression (N = 390). The 6-factor correlated model demonstrated the best fit across samples, whereas the 1- and 2-factor models had poor fit. The higher order model also showed relatively poor fit across samples, suggesting it is not representative of the relationship between subscale factors and a general self-compassion factor. The bifactor model, however, had acceptable fit in the student, community, and meditator samples. Although fit was suboptimal in the clinical sample, results suggested an overall self-compassion factor could still be interpreted with some confidence. Moreover, estimates suggested a general self-compassion factor accounted for at least 90% of the reliable variance in SCS scores across samples, and item factor loadings and intercepts were equivalent across samples. Results suggest that a total SCS score can be used as an overall mesure of self-compassion.     

Using the Research Domain Criteria Framework to Explore Associations Between MMPI–2–RF Constructs and Physiological Variables Assessed by Eye-Tracker Technology

The National Institute of Mental Health has proposed a paradigm shift in the conceptualization of psychopathology, abandoning the traditional categorical model in favor of one based on hierarchically organized dimensional constructs (Insel et al., 2010 Insel, T., Cuthbert, B., Garvey, M., Heinssen, R., Pine, D. S., Quinn, K., … Wang, P. (2010). Research domain criteria (RDoC): Toward a new classification framework for research on mental disorders. American Journal of Psychiatry, 167, 748–751.[Crossref], [PubMed], [Web of Science ®] , [Google Scholar]). One explicit goal of this initiative, the Research Domain Criteria (RDoC) project, is to facilitate the incorporation of newly available neurobiologic variables into research on psychopathology. The Minnesota Multiphasic Personality Inventory–2–Restructured Form (MMPI–2–RF; Ben-Porath &; Tellegen, 2008/2011 Ben-Porath, Y., &; Tellegen, A. (2011). Minnesota Multiphasic Personality Inventory–Restructured Form: Manual for administration, scoring, and interpretation. Minneapolis: University of Minnesota Press. (Original work published 2008) [Google Scholar]) represents a similar paradigm shift, also adopting a hierarchical arrangement of dimensional constructs. This study examined associations between MMPI–2–RF measures of psychopathology and eye-movement metrics. Participants were college students (n = 270) who completed the MMPI–2–RF and then viewed a sequence of 30-s video clips. Results show a pattern of positive correlations between pupil size and emotional/internalizing dysfunction scales when viewing video eliciting negative emotional reactions, reflecting greater arousability in individuals with higher scores on these measures. In contrast, when viewing stimuli depicting angry, threatening material, a clear pattern of negative correlations was found between pupil size and behavioral/externalizing trait measures. These data add to the construct validity of the MMPI–2–RF and support the use of the RDoC matrix as a framework for research on psychopathology.