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.     

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.     

Human responses in assessing object relations subscales of the Psychoanalytic Rorschach Profile

The Rorschach test is often used to assess object relations. This research examined whether human responses are necessary for a valid assessment.     

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.     

Strength of visual percept generated by famous faces perceived without awareness: effects of affective valence, response latency, and visual field

Participants who were unable to detect familiarity from masked 17 ms faces (Stone and Valentine, 2004 and Stone and Valentine, in press-b) did report a vague, partial visual percept. Two experiments investigated the relative strength of the visual percept generated by famous and unfamiliar faces, using masked 17 ms exposure. Each trial presented simultaneously a famous and an unfamiliar face, one face in LVF and the other in RVF. In one task, participants responded according to which of the faces generated the stronger visual percept, and in the other task, they attempted an explicit familiarity decision. The relative strength of the visual percept of the famous face compared to the unfamiliar face was moderated by response latency and participants' attitude towards the famous person. There was also an interaction of visual field with response latency, suggesting that the right hemisphere can generate a visual percept differentiating famous from unfamiliar faces more rapidly than the left hemisphere. Participants were at chance in the explicit familiarity decision, confirming the absence of awareness of facial familiarity.     

Psychometric evaluation of the restructured clinical scales of the MMPI-2

Conceptual overlap and heterogeneity have long been noted as weaknesses of the Minnesota Multiphasic Personality Inventory's clinical scales. Restructured clinical (RC) scales recently were developed to address these concerns (A. Tellegen et al., 2003). The authors evaluated the psychometric properties of the RC scales in psychology clinic clients (N=285) and military veterans (N=567). The RC scales were as internally consistent as the clinical scales and correlated strongly with their original counterparts (except for RC3/Hysteria). They also were less intercorrelated, produced conceptually clearer relations with measures of personality and psychopathology, and yielded somewhat greater incremental utility than the clinical scales. Thus, the RC scales demonstrated several psychometric strengths while utilizing 60% fewer items, but the 2 sets of scales cannot be used interchangeably. Interpretive considerations are discussed.     

Individual differences in susceptibility to experimentally induced phantom sensations

We investigated individual differences in susceptibility to two vibration-induced phantom illusions, i.e. illusory arm extension and nose prolongation (“Pinocchio illusion”). Vibration was applied to the biceps brachii tendon of 32 healthy participants. Susceptibility to the illusions was quantified by vividness ratings and by ratings of the amount of illusory position changes of the arm and illusory shape changes of the nose. Participants also completed the Perceptual Aberration (PA) and the Need for Cognition (NFC) inventories. PA reflects the frequency of spontaneously experienced body schema alterations and NFC a person's tendency to cognitively structure experiences. PA was positively correlated with participants’ susceptibility to illusory arm extension and, exclusively for men, also to nose elongation. A high NFC was weakly associated with a high susceptibility for the Pinocchio illusion. By inference, these findings indicate a physiological basis of PA and a cognitive mediation of experimentally induced phantom sensations.     

Perceiving while acting: action affects perception

In two experiments we studied how motor responses affect stimulus encoding when stimuli and responses are functionally unrelated and merely overlap in time. Such R-S effects across S-R assignments have been reported by Schubö, Aschersleben, and Prinz (2001), who found that stimulus encoding was affected by concurrent response execution in the sense of a contrast (i.e., emphasizing differences). The present study aimed at elucidating the mechanisms underlying this effect. Experiment 1 studied the time course of the R-S effect. Contrast was only obtained for short intertrial intervals (ITIs). With long ITIs contrast turned into assimilation (i.e., emphasizing similarities). Experiment 2 excluded an interpretation of the assimilation effect in terms of motor repetition. Our findings support the notion of a shared representational domain for perception and action control, and suggest that contrast between stimulus and response codes emerges when two S-R assignments compete with each other in perception. When perceptual competition is over, assimilation emerges in memory.