Evidence for positive mood buffering among college student drinkers

Positive experiences play an important role in buffering the effects of negative experiences. Although this process can play out in a myriad of contexts, the college context is one of particular importance because of significant concerns about student stress levels and alcohol abuse. Building on evidence that at least some students drink in response to negative experiences, we considered the possibility that positive moods would moderate college student negative mood-drinking relationships. Using a Web-based daily process study of 118 (57% women) undergraduate student drinkers, the authors reveal that positive moods indeed buffer the effects of negative moods on student drinking, depending on the mood and drinking context. Furthermore, the buffering of ashamed mood appears to explain the buffering of other negative moods. Implications of these findings are considered in terms of the relationship between negative self-awareness and drinking to cope.     

The influence of dominant versus non-dominant hand on event and emergent motor timing

It has been hypothesized that timing in tapping utilizes event timing; a clock-like process, whereas timing in circle drawing is emergent. Three experiments examined timing in tapping and circle drawing by the dominant and non-dominant hand. Participants were right-hand dominant college aged males and females. The relationship between variance and the square of the timed interval (the Weber fraction), thought to capture clock-like timekeeping processes, was compared. Furthermore, timing variance was decomposed into a clock and a motor component. The slopes for timing were different for dominant hand tapping and circle drawing, but equal for non-dominant and dominant hand tapping. Negative lag one covariance, consistent with motor implementation variability, was found for non-dominant but not for dominant hand circle drawing (Experiment 1). Practice did not influence this relation (Experiment 2). A significant correlation for clock variability was found between non-dominant hand circle drawing and tapping (Experiment 3). Collectively, these findings indicate that event timing is shareable across hands while emergent timing is specific to an effector. Emergent timing does not appear to be obligatory for the non-dominant hand in circle drawing. We suggest that the use of emergent timing might depend upon the extensive practice experienced by a person's dominant hand.     

Cortical correlates of impaired self-regulation in personality disordered patients with traits of psychopathy

Psychopathic personality disordered patients would, by virtue of a failure to self-regulate, be expected to show diminished amplitudes of feedback-related brain potentials. Among a sample of personality disordered patients detained at different levels of security, those who met a Psychopathy Checklist (PCL) criterion of 25 or above were identified (N = 27). Their event-related brain potentials (ERPs), together with those of their nonpsychopathic counterparts (N = 22) and healthy male controls (N = 20), were measured while they performed a visual Go/No Go task, with feedback given for correct and incorrect performance. Psychopathic patients showed a significantly reduced amplitude of an early frontal negative ERP component maximally evoked by negative feedback, and a high rate of errors of commission. Findings are consistent with the idea that psychopathic patients' unsuccessful attempts to self-regulate reflect a cognitive deficit characterised by a failure to attend and respond to a mismatch between expected and obtained outcomes.     

Individual differences in cardiovascular reactions to stress and cigarette smoking

The present study examined the stability of cardiovascular reactions to psychological stress and cigarette smoking, and the extent to which cardiovascular reactions to stress were predictive of cardiovascular reactions to smoking. Thirty subjects were given an initial test involving two repetitions of mental arithmetic stress and paced smoking while blood pressure and heart rate were measured. Two months later, 26 of these subjects were retested in the same paradigm. Large and stable individual differences were observed in cardiovascular reactivity to both stress and smoking. Moreover, for systolic and diastolic blood pressure, but not heart rate, reactions to stress were modestly correlated with reactions to cigarette smoking. These results are consistent with the possibility that level of reactivity to cigarette smoking may constitute a risk factor for coronary heart disease, and that one or more common variables may mediate the magnitude of blood pressure reactivity to both stress and cigarette smoking.     

Right hemispheric specialization for mental imagery: A review of the evidence

An implicit assumption in the literature on functional hemispheric asymmetry is that the right hemisphere plays a special role in mental imagery. Using a definition of mental imagery as quasi-perceptual experience, we draw distinctions among visual imagery, visual recognition memory, and visuospatial abilities. We then review the research literature to evaluate the hypothesis that mental imagery is a specialized function of the right cerebral hemisphere, and find that it receives little unambiguous support. Case reports of loss of imagery are no more frequent with right than with left unilateral brain damage. Systematic studies of brain-injured patients provide some support for the hypothesis, but are also consistent with the alternative hypothesis of bilateral representation of imagery. Commissurotomized patients report dreaming and being able to form visual images. Behavioral and psychophysiological studies of non-brain-injured patients either fail to provide evidence in favor of the hypothesis or can be interpreted as compatible with the alternate hypothesis of bilateral hemispheric involvement in imagery. We conclude that there is, presently, insufficient empirical basis for considering imagery a right hemispheric function. We then discuss implications of this conclusion for future research.