Neuropsychological executive functioning in children at elevated risk for alcoholism: findings in early adolescence

One component of individual risk for alcoholism may involve cognitive vulnerabilities prodromal to alcoholism onset. This prospective study of 198 boys followed between 3 and 14 years of age evaluated neurocognitive functioning across three groups who varied in familial risk for future alcoholism. Measures of intelligence, reward-response, and a battery of neuropsychological executive and cognitive inhibitory measures were used. Executive functioning weaknesses were greater in families with alcoholism but no antisocial comorbidity. IQ and reward-response weaknesses were associated with familial antisocial alcoholism. Executive function effects were clearest for response inhibition, response speed, and symbol-digit modalities. Results suggest that executive deficits are not part of the highest risk, antisocial pathway to alcoholism but that some executive function weaknesses may contribute to a secondary risk pathway.     

Difficulties in comprehending causal relations among children with ADHD: the role of cognitive engagement

The present study examined whether time spent in long looks (i.e., >or=15 s), an index of cognitive engagement, would account for differences between children with attention deficit hyperactivity disorder (ADHD) and comparison children in understanding causal relations. Children viewed two televised stories, once in the presence of toys and once in their absence. Dependent variables were visual attention and questions tapping factual information and causal relations. Comparison children answered significantly more causal relations questions than did the children with ADHD, but only in the toys-present condition. Four lines of evidence revealed that the difficulties children with ADHD had in answering causal relations questions in the toys-present condition could be linked specifically to this group's decreased time spent in long looks.     

Illicit drug use and risky sexual behavior among African American and Puerto Rican urban adolescents: the longitudinal links

The authors assessed whether (a) early illicit drug use predicted later risky sexual activity, (b) early risky sex predicted later illicit drug use, and (c) common factors affected both risky sexual behavior and illicit drug use. African American and Puerto Rican youth completed questionnaires in their classrooms at Time 1 (T1) and face-to-face interviews with the authors in their homes 5 years later at Time 2 (T2). Logistic regression analyses showed the association between T1 illicit drug use and T2 risky sexual activity and between T1 risky sexual behavior and T2 illicit drug use. With few exceptions, T1 illicit drug use was associated with all of the T2 risky sexual behaviors. After controlling for demographic factors, the authors found that multiple sex partners at T1 was not related to illicit drug use at T2. Condom use at T1 was related to illicit drug use at T2, whereas sexually transmitted diseases and adolescent pregnancy were not related to this drug use. The findings indicated that assessments of and treatments for substance use should focus on the risky sexual behaviors that seem to accompany illicit drug use.     

Influence of consonantal context on the pronunciation of vowels: a comparison of human readers and computational models

In two experiments, we found that college students' pronunciations of vowels in nonwords are influenced both by preceding and following consonants. The predominance of rimes in previous studies of reading does not appear to arise because readers are unable to pick up associations that cross the onset-rime boundary, but rather because English has relatively few such associations. Comparisons between people's vowel pronunciations and those produced by various computational models of reading showed that no model provided a good account of human performance on nonwords for which the vowel shows contextual conditioning. Possible directions for improved models are suggested.     

A half century of scalloping in the work habits of the United States Congress

It has been suggested that the work environment of the United States Congress bears similarity to a fixed-interval reinforcement schedule. Consistent with this notion, Weisberg and Waldrop (1972) described a positively accelerating pattern in annual congressional bill production (selected years from 1947 to 1968) that is reminiscent of the scalloped response pattern often attributed to fixed-interval schedules, but their analysis is now dated and does not bear on the functional relations that might yield scalloping. The present study described annual congressional bill production over a period of 52 years and empirically evaluated predictions derived from four hypotheses about the mechanisms that underlie scalloping. Scalloping occurred reliably in every year. The data supported several predictions about congressional productivity based on fixed-interval schedule performance, but did not consistently support any of three alternative accounts. These findings argue for the external validity of schedule-controlled operant behavior as measured in the laboratory. The present analysis also illustrates a largely overlooked role for applied behavior analysis: that of shedding light on the functional properties of behavior in uncontrolled settings of considerable interest to the public.     

How are social identities linked to self-conception and intergroup orientation? The moderating effect of implicit theories

Social identity approaches assume that social identification affects both self-conception and intergroup orientation. The authors contend that such social identification effects are accentuated when people hold a fixed view of human character and attribute immutable dispositions to social groups. To these individuals, social identities are immutable, concrete entities capable of guiding self-conception and intergroup orientation. Social identification effects are attenuated when people hold a malleable view of human character and thus do not view social identities as fixed, concrete entities. The authors tested and found support for this contention in three studies that were conducted in the context of the Hong Kong 1997 political transition, and discussed the findings in terms of their implications for self-conceptions and the meaning of social identification.     

Temporal integration of speech prosody is shaped by language experience: an fMRI study

Differences in hemispheric functions underlying speech perception may be related to the size of temporal integration windows over which prosodic features (e.g., pitch) span in the speech signal. Chinese tone and intonation, both signaled by variations in pitch contours, span over shorter (local) and longer (global) temporal domains, respectively. This cross-linguistic (Chinese and English) study uses functional magnetic resonance imaging to show that pitch contours associated with tones are processed in the left hemisphere by Chinese listeners only, whereas pitch contours associated with intonation are processed predominantly in the right hemisphere. These findings argue against the view that all aspects of speech prosody are lateralized to the right hemisphere, and promote the idea that varying-sized temporal integration windows reflect a neurobiological adaptation to meet the 'prosodic needs' of a particular language.     

Cortical morphology associated with language function in neurofibromatosis,type I

Neurofibromatosis, type I (NF-I) is associated with verbal and nonverbal neuropsychological deficits and neuroanatomical anomalies. Few relationships between CNS abnormalities and cognitive function in this population, however, have been found. Reading disabilities and developmental language impairments in the general population have been associated with particular morphologic features in inferior frontal gyrus (IFG) and Heschl's gyrus (HG). We compared the morphology of these regions in children with NF-I and controls. Verbal skills in NF-I were related to IFG morphology, such that individuals with NF-I who showed "typical" gyral patterns in the right hemisphere performed worse across language measures than those showing an extra "atypical" gyrus. A doubling of HG in the left and right hemispheres was also significantly associated with performance on several neuropsychological measures. This is the first study to link regional gyral morphology with language function in NF-I. A possible molecular basis for the observed relationships is discussed.     

Affect- and self-based models of relationships between daily events and daily well-being

The present study examined affect- self-based explanatory models of relationships between daily events and daily well-being. Twice a week for up to 10 weeks, participants described the events that occurred each day and provided measures of their daily affect, self-esteem, and depressogenic thinking. Participants also provided trait-level measures of affect, depression, and self-esteem. Measures of daily well-being representing each model covaried jointly and independently with daily negative and positive events. Positive events buffered the effects of negative events on daily self-esteem and daily depressogenic thinking, whereas there was no buffering effect for daily affect. More depressed people were more reactive to positive events, and those higher in trait PA were less reactive to negative events. Buffering effects for self-esteem were pronounced for those with lower trait self-esteem, and buffering effects for daily depressogenic adjustment were now more pronounced for those with higher trait negative affect. The results suggest that affect- and self-based models provide complementary perspectives on relationships between psychological well-being and daily events.