Does response variability predict distractibility among adults with attention-deficit/hyperactivity disorder?

Increased intraindividual variability in response time (RTSD) has been observed reliably in attention-deficit/hyperactivity disorder (ADHD) and has often been used as a measure of inattention. RTSD is assumed to reflect attentional lapses and distractibility, though evidence for the validity of this connection is lacking. We assessed whether RTSD is an indicator of inattention by comparing RTSD on the stop-signal task (SST) with performance on the delayed oculomotor response (DOR) task, a measure of distractibility. Participants included 30 adults with ADHD and 28 controls. Participants completed the SST and the DOR task, which measured subjects' ability to maintain attention and avoid distraction by inhibiting reflexive saccades toward distractors. On the SST, the ADHD group was slower to inhibit than were controls, indicating poorer inhibitory control in ADHD. The ADHD group also displayed slower reaction times (RTs), greater RTSD, and more omission errors. On the DOR task, the ADHD group displayed more premature saccades (i.e., greater distractibility) than did controls. Greater variability in RT was associated with increased distraction on the DOR task, but only in ADHD participants. Results suggest that RTSD is linked to distractibility among adults with ADHD and support the use of RTSD as a valid measure of inattention in ADHD.     

Extraversion and its positive emotional core--further evidence from neuroscience

Converging evidence from self-report data demonstrated that extraversion and dispositional positive affect are systematically related. Several authors therefore considered positive affect as the conceptual core of extraversion. Because the ventral striatum is regarded as a core region in the physiological basis of extraversion, the present study examines the importance of this neural substrate with a special focus on positive affect. Baseline cerebral blood flow was measured in 38 participants and regressed to the extraversion and dispositional positive affect scales. Partial correlational and indirect-effects analyses indicated that striatal blood flow was no longer associated with extraversion when positive affect was statistically controlled. In contrast, when extraversion was statistically controlled, striatal blood flow was still associated with positive affect. This finding suggests that the striatal region is not a biological basis of extraversion per se. Rather, this region sustains positive affect, which in turn appears to be a core feature of extraversion.     

The effect of self-distancing on adaptive versus maladaptive self-reflection in children

Although children and adolescents vary in their chronic tendencies to adaptively versus maladaptively reflect over negative feelings, the psychological mechanisms underlying these different types of self-reflection among youngsters are unknown. We addressed this issue in the present research by examining the role that self-distancing plays in distinguishing adaptive versus maladaptive self-reflection among an ethnically and socioeconomically diverse sample of fifth-grade public schoolchildren. Children were randomly assigned to analyze their feelings surrounding a recent anger-related interpersonal experience from either a self-immersed or self-distanced perspective. They then rated their negative affect and described in writing the stream of thoughts they experienced when they analyzed their feelings. Children's stream-of-thought essays were content analyzed for the presence of recounting statements, reconstruing statements, and blame attributions. Path analyses indicated that children who analyzed their feelings from a self-distanced perspective focused significantly less on recounting the "hot," emotionally arousing features of their memory (i.e., what happened to me?) and relatively more on reconstruing their experience. This shift in thought content--less recounting and more reconstruing--led children in the self-distanced group to blame the other person involved in their recalled experience significantly less, which in turn led them to display significantly lower levels of emotional reactivity. These findings help delineate the psychological mechanisms that distinguish adaptive versus maladaptive forms of self-reflection over anger experiences in children. Their basic findings and clinical implications are discussed.     

Individual differences in a within-subjects risky-choice framing study

A within-subjects study investigated several different risky-choice framing problems patterned after Kahneman and Tversky’s classic economic game, the Asian Disease problem, but included variations to increase generality. Risk-style and thinking-style were utilized to predict individual differences in response to the framing problems. Significant framing effects were found at both the item and composite level. Individual difference effects were rare when framing was strictly defined as a preference reversal. When a more encompassing preference shift defined framing, risk-averse individuals (measured by the Choice Dilemmas Questionnaire) and those scoring high on experiential (heuristic) thinking were more likely to show a framing effect. Discussion focuses on the meaning of these results in terms of individual susceptibility to framing.     

Fast automatic translation and morphological decomposition in Chinese-English bilinguals

In this study, we investigated automatic translation from English to Chinese and subsequent morphological decomposition of translated Chinese compounds. In two lexical decision tasks, Chinese-English bilinguals responded to English target words that were preceded by masked unrelated primes presented for 59 ms. Unbeknownst to participants, the Chinese translations of the words in each critical pair consisted of a fully opaque compound word (i.e., a compound with two constituent morphemes that were semantically unrelated to the compound) and a monomorphemic word that was either the first or the second morpheme of the compound. The data revealed that bilinguals responded faster to English word pairs whose Chinese translations repeated the first morpheme than to English word pairs whose Chinese translations did not repeat the first morpheme, but no effect of hidden second-morpheme repetition was found. This effect of hidden first-morpheme repetition suggests that participants translated English words to Chinese and decomposed the translated compounds into their constituent morphemes. Because the primes were presented for only 59 ms, translation and morphological decomposition must be fast and automatic.