Externalizing psychopathology and the error-related negativity

Prior research has demonstrated that antisocial behavior, substance-use disorders, and personality dimensions of aggression and impulsivity are indicators of a highly heritable underlying dimension of risk, labeled externalizing. Other work has shown that individual trait constructs within this psychopathology spectrum are associated with reduced self-monitoring, as reflected by amplitude of the error-related negativity (ERN) brain response. In this study of undergraduate subjects, reduced ERN amplitude was associated with higher scores on a self-report measure of the broad externalizing construct that links these various indicators. In addition, the ERN was associated with a response-locked increase in anterior theta (4-7 Hz) oscillation; like the ERN, this theta response to errors was reduced among high-externalizing individuals. These findings suggest that neurobiologically based deficits in endogenous action monitoring may underlie generalized risk for an array of impulse-control problems.     

Religious Doubt and Mental Health Across the Lifespan

The current study examined the connections among religious doubt, mental health, and aging in a nationwide sample of individuals 18 years and older (N = 1629). Findings indicate that that religious doubt emerging from the recognition of suffering and evil in the world has a deleterious impact on mental health. Results also show that as people grow older, religious doubts continue to be associated with psychopathology, but the magnitude of this association becomes weaker across age categories. In other words, the impact of doubt on mental distress declines as one ages. These effects were found across various measures of mental distress, including depression, general anxiety, interpersonal sensitivity, paranoia, hostility, and obsessive-compulsive symptoms. Findings are explored within the context of psychosocial development and the experiential trajectory of religious maturity.     

Homophone effects in visual word recognition depend on homophone type and task demands.

This experiment examined how the characteristics of homophones and their mates influence homophone effects, as a function of task demands. Two types of homophones were presented: 1) low-frequency homophones with higher-frequency mates that are not animal names (e.g., maid--made), and 2) low-frequency homophones with mates that are, on average, of equivalent frequency and are animal names (e.g., foul--fowl). We observed a double dissociation: In the lexical decision task (LDT), there was a homophone effect for the first type of homophones but not for the second, whereas in the semantic categorization task (SCT) the opposite was true. These results suggest that in these tasks the effects of homophony arise when the homophone's mate creates competition in terms of the type of processing emphasized in the task, namely, orthographic processing in the LDT and semantic processing in the SCT.     

Visual processing speed: effects of auditory input on visual processing

The ability to process simultaneously presented auditory and visual information is a necessary component underlying many cognitive tasks. While this ability is often taken for granted, there is evidence that under many conditions auditory input attenuates processing of corresponding visual input. The current study investigated infants' processing of visual input under unimodal and cross-modal conditions. Results of the three reported experiments indicate that different auditory input had different effects on infants' processing of visual information. In particular, unfamiliar auditory input slowed down visual processing, whereas more familiar auditory input did not. These results elucidate mechanisms underlying auditory overshadowing in the course of cross-modal processing and have implications on a variety of cognitive tasks that depend on cross-modal processing.     

Comparing older and younger adults in an event-based prospective memory paradigm containing an output monitoring component

Two experiments with younger and older adults were conducted to investigate the output-monitoring component of event-based prospective memory. In the standard form of the task, participants must remember to press a key when a certain class of items is encountered. To evaluate output monitoring, event-based cues were repeated and participants were asked to press a different key if they could remember that an earlier response was made to a particular cue. Younger adults forgot fewer of their successful responses, but displayed a distinct bias to claim that they had responded earlier when actually they had forgotten to respond. By contrast, older adults displayed this bias much less frequently. Elaborated responding to cues had the effect of improving the performance of younger, but not older adults. The results are discussed in terms of natural repetitions and omission errors that might be made in everyday prospective memory tasks.     

Serotonin transporter genetic variation and biased attention for emotional word stimuli among psychiatric inpatients

The short allele in a variable repeat sequence of the promoter region of the serotonin transporter gene (5-HTTLPR) has been associated with stronger activation in brain regions critical for processing emotional stimuli. The authors examined whether variants of the 5-HTTLPR promoter polymorphism were also associated with individual differences in attentional biases for emotional stimuli. Words related to anxious and dysphoric emotional states were presented to psychiatric inpatients in a standard dot-probe reaction time task. Compared with participants with two long alleles, carriers of the short 5-HTTLPR allele exhibited a stronger attentional bias for anxious word stimuli. No genetic group difference was observed for dysphoric word stimuli. Findings from this preliminary study highlight the potential for integrating genetic and cognitive models of psychopathology.     

Gender differences and developmental change in externalizing disorders from late adolescence to early adulthood: A longitudinal twin study

Using data from over 1,000 male and female twins participating in the Minnesota Twin Family Study, the authors examined developmental change, gender differences, and genetic and environmental contributions to the symptom levels of four externalizing disorders (adult antisocial behavior, alcohol dependence, nicotine dependence, and drug dependence) from ages 17 to 24. Both men and women increased in symptoms for each externalizing disorder, with men increasing at a greater rate than women, such that a modest gender gap at age 17 widened to a large one at age 24. Additionally, a mean-level gender difference on a latent Externalizing factor could account for the mean-level gender differences for the individual disorders. Biometric analyses revealed increasing genetic variation and heritability for men but a trend toward decreasing genetic variation and increasing environmental effects for women. Results illustrate the importance of gender and developmental context for symptom expression and the utility of structural models to integrate general trends and disorder-specific characteristics.