P300 amplitude, externalizing psychopathology, and earlier- versus later-onset substance-use disorder

P300 amplitude predicts substance use or disorder by age 21. Earlier- versus later-onset substance disorders may reflect different levels of an externalizing psychopathology dimension. P300 in adolescence may not be as strongly related to later-onset substance problems as it is to earlier-onset ones. In the present study, visual P300 amplitude was measured at age 17 in a community-representative sample of young men. Substance and externalizing disorders were assessed at approximately ages 17, 20, and 24. Earlier-onset (by age 20) substance disorder was associated with higher rates of externalizing disorders than were later-onset problems. P300 amplitude was reduced in subjects with earlier-onset substance disorders, relative to later-onset and disorder-free subjects. Amplitude was also reduced in subjects with an externalizing disorder but no substance disorder. Earlier-onset subjects had reduced P300, even in the absence of an externalizing disorder. The results could not be attributed to a concurrent disorder or to recent substance use at the time of the P300 recording. The findings are consistent with P300 indexing an externalizing spectrum. Earlier-onset substance disorders are more strongly related to P300 and externalizing than are later-onset problems.     

Egocentric organization of spatial activities in imagined navigation

Studies on spatial frameworks suggest that the way we locate objects in imagined environments is influenced by the physical and functional properties of the world and our body. The present study provides evidence that such an influence also characterizes imagined navigation. In Experiment 1, participants followed spatial directions to construct an imagined path, while either keeping constant or updating their orientation at each step. A pattern of step times diagnostic of spatial frameworks was obtained in the updated-orientation but not in the constant-orientation condition. In Experiment 2, participants performed the updated-orientation condition with two levels of external support for the reference frame being used. Step times conformed to the predictions of spatial frameworks in both conditions. Both experiments also provided support that the processes involved in imagined navigation exhibit the operator-operand dynamics of other mental skills previously documented in the mental arithmetic domain. These results reinforce Piaget's (1954) notion that spatial displacements and integer arithmetic share a set of structural characteristics     

Differences in heterosocial behavior and outcomes of ADHD-symptomatic subtypes in a college sample

The purpose of this study was to explore heterosocial relational outcomes in a college-aged sample showing symptoms of Attention-Deficit/Hyperactivity Disorder (ADHD). Using questionnaires and a behavioral observation task, dating, sexual, and social outcomes were examined in three groups: 24 non-ADHD controls, 27 ADHD-Combined (ADHD/C) Type, and 13 ADHD-Primarily Inattentive (ADHD/IA) Type. The ADHD/IA group showed a consistent pattern of passivity and inexperience and was perceived relatively negatively by female confederates, whereas the ADHD/C group reported increased sexual drive and early dating experience. The effects of externalizing comorbidity differed by DSM-IV ADHD subtype. These findings indicate that ADHD-symptomatic adults differ by DSM-IV subtype in the manifestation of heterosocial deficits. Results suggest specific and divergent types of psychosocial intervention with ADHD/C versus ADHD/IA clients.     

Choosing an inferior alternative

We show how decision makers can be induced to choose a personally inferior alternative, a strong violation of rational decision making. First, the inferior alternative is installed as the leading option by starting with information that supports this alternative. Then, the decision maker uses the natural process of distorting new information to support whichever alternative is leading. This leader-supporting distortion overcomes the inherent advantages of the superior alternative. The end result is a tendency to choose the self-identified inferior alternative. We trace the choice process to reveal the amount of distortion and its influence on preference. Self-reported awareness of distortion to support the inferior alternative is not related to the amount of distortion. The absence of valid awareness suggests that the manipulation that produces this preference violation is unlikely to be detected and that the distortion is unlikely to be corrected by the decision maker. As expected, given the lack of awareness, final confidence is just as high when the inferior alternative is chosen as when the superior one is. The discussion considers how to prevent an adversary from manipulating one's decisions using this technique.     

Tracking the what and why of speakers’ choices: Prosodic boundaries and the length of constituents

The rational speaker hypothesis (Clifton, Carlson, & Frazier, 2002) claims that speakers are selfconsistent, employing intonation in a manner consistent with their intended message. Preceding a constituent by a prosodic boundary that is not required by the grammar often signals that this constituent is not part of the immediately preceding phrase. However, speakers tend to place prosodic boundaries before and after long constituents. The question is whether prosodic boundaries will have a larger influence on listeners’ choice of an analysis when they flank short constituents than when they flank long ones. The results of two listening experiments indicate that they do, suggesting that listeners attend not just to properties of the input signal, but also to the reasons why speakers produce those properties.     

Prosodic phrasing is central to language comprehension

Words, like musical notes, are grouped together into phrases by their rhythmic and durational properties as well as their tonal pitch. This 'prosodic phrasing' affects the understanding of sentences. Many processing studies of prosody have investigated sentences with a single, grammatically required prosodic boundary, which might be interpreted strictly locally, as a signal to end the current syntactic unit. Recent results suggest, however, that the global pattern of prosodic phrasing is what matters in sentence comprehension, not just the occurrence or size of a single local boundary. In this article we claim that the impact of prosodic boundaries depends on the other prosodic choices a speaker has made. We speculate that prosody serves to hold distinct linguistic representations together in memory.     

Less is more: executive function and symbolic representation in preschool children

Executive function is recognized as a critical component of children's cognitive and social development. In two studies, a measure of executive function that had been used in research with chimpanzees was adapted for preschoolers. On this task, called Less Is More, children must point to a smaller reward (two candies) to receive a larger reward (five candies). In Study 1 (N= 101), performance was significantly related to age (3 vs. 4), verbal ability, and established measures of executive function. In Study 2 (N= 128), symbolic representations substituted for real candies in this task. Three-year-olds' performance improved significantly as a function of symbolic distancing. This research has implications for the role of symbol systems in the development of executive control over thought and action.     

Temperament, relationships, and young children's receptive cooperation with their parents

The authors studied receptive cooperation--a willing, eager stance toward parents--in 15-month-old children (N = 101) in broadly ranging contexts. Children's anger proneness and parents' responsiveness (both observed at 7 months) and children's attachment security (assessed in Strange Situation at 15 months) were examined as predictors of children's receptive cooperation at 15 months. In mother-child dyads, secure attachment was strongly associated with children's higher receptive cooperation. Maternal responsiveness in infancy also promoted children's future receptive cooperation, but its impact was moderated by child anger: Responsiveness had a positive effect for children who as infants were highly anger prone. In father-child dyads, the negative effect of anger proneness on receptive cooperation with father was significantly amplified for insecure children. Mother's responsiveness and child's secure attachment to the mother promoted child receptive cooperation with the father, but there were no similar effects for fathers.     

Etiologic connections among substance dependence,antisocial behavior,and personality: modeling the externalizing spectrum

A hierarchical biometric model is presented of the origins of comorbidity among substance dependence, antisocial behavior, and a disinhibited personality style. The model posits a spectrum of personality and psychopathology, united by an externalizing factor linked to each phenotype within the spectrum, as well as specific factors that account for distinctions among phenotypes within the spectrum. This model fit self-report and mother-report data from 1,048 male and female 17-year-old twins. The variance of the externalizing factor was mostly genetic, but both genetic and environmental factors accounted for distinctions among phenotypes within the spectrum. These results reconcile evidence for general and specific causal factors within the externalizing spectrum and offer the externalizing factor as a novel target for future research.     

Inhibition of attended processing during saccadic eye movements

People are unable to perform some, but not all, cognitive tasks while moving their eyes. A possible common denominator among disrupted processes is the use of attention. The present research proposes and tests an attentional suppression hypothesis to evaluate this claim. This hypothesis states that because attention is obligatorily allocated to a to-be-fixated location prior to the onset of a saccade, during saccadic events attentional resources are unavailable to direct processing associated with higher order cognitive tasks. Subjects were engaged in a task that combined saccades and shifts of attention across global and local levels of hierarchical figures. When the eyes did not move, this shift took place between stimulus presentations. When saccades intervened between the stimuli, the global-local shifts of attention were interrupted, suggesting that saccades suppress cognitive processes requiring attention.