Dependency,impulsivity, and self-harm: traits hypothesized to underlie the association between cluster B personality and substance use disorders

Cluster B personality disorders (PDs) (i.e., antisocial, borderline, histrionic, and narcissistic) typically show a high degree of comorbidity with substance use disorders (SUDs). Previous research suggests that the broad-based personality domains of Disinhibition and Negative Temperament/Neuroticism may be common factors to both types of disorders. Using a two-phase process (i.e., screening and follow-up), this study examined three lower-order personality traits (i.e., dependency, impulsivity, and self-harm) that fall within the Disinhibition and Neuroticism domains. The study evaluated the hypotheses that these traits (a) are related both to cluster B PDs and to SUDs; and (b) underlie the association between the two types of disorders. Results indicate that impulsivity and self-harm play a significant role in cluster B PDs and SUDs, as well as in their association with each other. However, dependency was not associated with either type of disorder. These results indicate that sets of individual traits can be of significant utility in understanding the comorbidity between PDs and SUDs.     

Oxytocin links mothering received,mothering bestowed and adult stress responses

We review recent discoveries that implicate oxytocin in the intergenerational transmission of similar levels of maternal behavior and acute stress responses in female rats. First, ICV-infused oxytocin antagonist decreased the display by nursing dams of pup-licking (PL) and arched-back nursing (ABN), but not other components of maternal behavior, and increased maternal self-grooming suggesting that oxytocin may shift the balance of oral grooming by dams away from themselves and toward pups. Second, oxytocin receptor concentrations in areas of the adult brain where oxytocin stimulates maternal behavior or diminishes anxiety and adrenal axis responses to acute stress were positively related to PL-ABN received during infancy. Third, oxytocin and oxytocin antagonist treatments of pups on postnatal days 2-10, respectively increased and decreased PL by the treated rats when adult and themselves nursing dams. This indicates that oxytocin activity in female pups, which may be regulated by PL-ABN received from their mothers, influences their adult levels of PL. These three lines of evidence suggest that oxytocin selectively enhances PL-ABN by rat dams, which then increases oxytocin activity in female pups and, thereby, facilitates their expression of central oxytocin receptors (and perhaps other aspects of central oxytocin systems) and, consequently, their adult PL-ABN frequencies and acute stress responses.     

Sleep-dependent hippocampal slow activity correlates with waking memory performance in humans

The positive effect of postlearning sleep on memory consolidation as well as the relationship between sleep-related memory processes and the hippocampal formation are increasingly clarified topics in neurobiology. However, the possibility of a stable relationship between waking mnemonic performance and sleep-dependent hippocampal electric activity is unexplored. Here we report a correlative analysis between sleep-dependent parahippocampal-hippocampal (pHip-Hip) electric activity recorded by foramen ovale (FO) electrodes and different types of memory performances in epileptic patients. Psychological testing was performed days or weeks before electrophysiological recordings. The relative spectral power of the slow activity (below 1.25 Hz) during deep non-REM (NREM) sleep at the right pHip-Hip region correlated positively with the visual memory performance according to Rey-Osterrieth Complex Figure Test (ROCFT). Along the posterior-anterior direction of the hippocampal formation a linear increasing of correlations was observed. The relative power of the activity below 1.25 Hz at the left pHip-Hip during phasic REM sleep correlated positively with verbal learning performance and mnemonic retention values according to ROCFT. It is concluded that the pHip-Hip structures' capacity of producing high amplitude and synchronized slow (< 1 Hz) oscillation during deep NREM sleep is related to the functional power of these structures. We hypothesize that the asymmetric (side-specific) propagation of ponto-geniculo-occipital (PGO) activity to the pHip-Hip region is related to the memory correlates of phasic REM sleep.     

Psychiatric patient- and informant-reported personality: predicting concurrent and future behavior

The authors investigated the criterion and incremental validity of personality reports from psychiatric patients and knowledgeable informants in predicting patient substance use, social and risky behaviors, and psychological distress. Patient and informant reports of patient personality and behavior were collected from an adult psychiatric sample (N = 94). Hierarchical regressions indicated that patient reports of personality accounted for significant variance in both concurrent (17%-42%) and future behavior assessed 1 year later (17%-40%). Informant reports contributed significantly to the prediction of several behaviors and most strongly to social behaviors. Behaviors were predicted equally well by self-reports and informant reports in prospective as in concurrent regressions. Thus, both patient and informant reports of personality contribute importantly to prediction of behavior, and predictive ability is stable across time.     

Word Frequency Effects on the Processing of Subject–Verb Number Agreement

This paper examines the role of word frequency in the computation of subject–verb number agreement. Previous research in both production and comprehension has demonstrated that processing difficulties can arise in sentence structures containing a singular subject noun followed by a plural distractor noun, as in The key to the cabinets.¨ A whole sentence reading task was employed to determine whether the relative frequency with which the distractor noun appears in its singular or plural form would affect the degree of processing difficulty experienced by readers. Results suggest that the agreement process is, indeed, sensitive to this factor and this finding is compatible with activation-based accounts of the implementation of number agreement.     

Family functioning and early onset of sexual intercourse in Latino adolescents

The purpose of this study was to identify factors associated with early onset of sexual intercourse. Within an ecological system's conceptual framework, familial factors associated with early onset of sexual activity were identified in a sample of 425 adolescents from San Juan metro area schools. Measures included questions about sexual activity, sexual permissiveness, and such familial variables as: discipline, parental supervision, and parental support. Significant relationships were observed between early onset of sexual intercourse and parental supervision, discipline, parental support, and parents' marital status. Results suggest the key role of parents and family in prevention of HIV-risk behaviors among adolescents in terms of delaying sexual onset. Overall, the study described youths who postponed sexual activity as having greater support, supervision, and parental involvement.     

From egocentric to exocentric spatial orientation: development of posture control in bimanual and trunk inclination tasks

The authors investigated the emergence of independent control of body segments in bimanual tasks involving either voluntary or involuntary trunk motion by tracking the transition from an ego- to an exocentric mode of postural control during childhood (i.e., from body-referenced orientation to externally referenced action). A paradigm combining a seated manual task and various trunk manipulations described the coordination strategies used by 24 children at different ages (2 to 9 years) and by adults. The following questions were asked: (a) When do children begin to dissociate upper limb movements from those of the trunk? (b) What segmental strategies are exhibited by each age group (2-3, 4-6, and 7-9 years, and adults)? Kinematic analyses revealed that younger children (2-6 years) used either the trunk or the support surface as reference to orient the limbs. Older children (7-9 years) began to use a gravitational reference frame similar to that of adults; they uncoupled upper limb motion from the trunk in either voluntary or imposed conditions. Young children patterned the forearm trajectory after the initiating segment (support surface or the trunk), thus reducing the degrees of freedom during the dual task. Echoing previous reports, 7-9 years of age appears to be a critical period in which children master postural control and develop an internal representation of body scheme.     

Incremental exercise in dynamic visual acuity

As research is limited the purpose of this study was to investigate dynamic visual acuity while cycling at different exercise loads. Accuracy of dynamic visual acuity scores of 20 college-age participants was analyzed by a repeated-measures analysis of variance which indicated improved dynamic visual acuity during cycling as the intensity of exercise increased. A retention test conducted two days after testing yielded evidence of trainability of dynamic visual acuity. In the discussion findings were compared to other visual functions associated with exercise.