Localized disruption of Narp in medial prefrontal cortex blocks reinforcer devaluation performance

Neuronal activity regulated pentraxin (Narp) is a secreted protein that regulates α-amino-3-hydroxyl-5-methyl-4-isoxazole-propionate receptors (AMPAR) aggregation and synaptogenesis. Mapping of Narp-positive neurons in brain has revealed it is prominently expressed in several limbic system projection pathways. Consistent with this localization pattern, Narp knockout mice show deficits in using the current value of a reinforcer to guide behavior, a critical function of the limbic system. To help assess whether this behavioral deficit is due to impairment of synaptogenesis during development or in modulating synaptic signaling in the mature brain, we have used a dominant negative Narp viral construct which blocks trafficking of endogenous Narp to axons. Focal injection of this viral construct into the medial prefrontal cortex (mPFC) of adult mice, a region containing Narp-positive projection neurons, blocked reinforcer devaluation. Thus, these results indicate that Narp released from mPFC neurons plays a key role in mediating synaptic changes underlying instrumental reinforcer devaluation.     

Effects of Kindermusik training on infants’ rhythmic enculturation

Phillips‐Silver and Trainor (2005) demonstrated a link between movement and the metrical interpretation of rhythm patterns in 7‐month‐old infants. Infants bounced on every second beat of a rhythmic pattern with no auditory accents later preferred to listen to an accented version of the pattern with accents every second beat (duple or march meter), whereas infants bounced on every third beat of the same rhythmic pattern preferred to listen to a version with accents every third beat (triple or waltz meter). The present study compared infants participating in Kindermusik classes with infants not participating in music classes. In Kindermusik classes infants receive enriched experience moving to music. Following Western musical norms, the majority of the music samples in the classes are in duple meter. During the preference test, Kindermusik infants listened longer overall, indicating heightened interest in musical rhythms. Both groups listened longer to the accented version that matched how they had been bounced, but only the Kindermusik group showed a stronger preference in the case of duple bouncing than in the case of triple bouncing. We conclude that musical classes for infants can accelerate the development of culture‐specific metrical perception.     

Evidence for intact memory-guided attention in school-aged children

Visual scenes contain many statistical regularities such as the likely identity and location of objects that are present; with experience, such regularities can be encoded and can ultimately facilitate the deployment of spatial attention to important locations. Memory-guided attention has been extensively examined in adults with the 'contextual cueing' paradigm and has been linked to specific neural substrates – a medial temporal lobe (MTL)-frontoparietal network. However, it currently remains unknown when this ability comes 'online' during development. Thus, we examined the performance of school-aged children on an age-appropriate version of the contextual cueing paradigm. Children searched for a target fish among distractor fish in new displays and in 'old' displays on a touchscreen computer. Old displays repeated across blocks of trials and thus provided an opportunity for prior experience with the invariant configuration of the stimuli to guide attentional deployment. We found that over time children searched old displays significantly faster than new displays, thus revealing intact memory-guided attention and presumed function of an MTL-frontoparietal network in 5- to 9-year-olds. More generally, our findings suggest that children are remarkably sensitive to the inherent structure of their visual environment and this enables attentional deployment to become more efficient with experience.     

The Caregiver Eating Messages Scale: Development and psychometric investigation

Certain caregiver eating messages – restriction of food intake and pressures to eat – are associated with body dissatisfaction and eating disturbances among young girls. This study explored whether these messages are also associated with body attitudes and eating behaviors of young adult women and men. The Caregiver Eating Messages Scale was developed to measure this construct. Two studies (Ns = 238, 288) indicated that it contained two factors (restrictive/critical messages and pressure to eat messages) and yielded internally consistent, stable, and valid scores. Both factors were positively related to women's BMI, and restrictive/critical messages were positively related to men's BMI. Restrictive/critical messages predicted lower perceived familial body acceptance and intuitive eating and higher perceived familial pressure to be lean and disordered eating. Restrictive/critical messages predicted participants’ body attitudes indirectly via their perceptions of their family's attitude toward their body, with one exception: restrictive/critical messages uniquely predicted men's body appreciation.     

Effects of Ingroup Bias and Gender Role Violations on Acquaintance Rape Attributions

Two studies of ethnically diverse US college students from northern California examined whether ingroup bias and gender norm violations influence acquaintance rape attributions (Study 1, N?=?118; Study 2, N?=?140). Participants read vignettes depicting acquaintance rape and completed questionnaires. Victims were part of participants’ ingroup or outgroup. Study 1 manipulated the victim’s sexual history (chaste or promiscuous). Study 2 manipulated the victim’s alcohol use (sober or intoxicated). Ingroup victims were perceived more positively than outgroup victims if the victims were promiscuous or intoxicated. More guilt was attributed to rapists of ingroup victims than outgroup victims if the victims were promiscuous or intoxicated. Findings are examined in relation to ingroup bias and gender norm violations.     

Academic Achievement Over 8 Years Among Children Who Met Modified Criteria for Attention-deficit/Hyperactivity Disorder at 4–6 Years of Age

The predictive validity of symptom criteria for different subtypes of ADHD among children who were impaired in at least one setting in early childhood was examined. Academic achievement was assessed seven times over 8 years in 125 children who met symptom criteria for ADHD at 4–6 years of age and in 130 demographically-matched non-referred comparison children. When intelligence and other confounds were controlled, children who met modified criteria for the predominantly inattentive subtype of ADHD in wave 1 had lower reading, spelling, and mathematics scores over time than both comparison children and children who met modified criteria for the other subtypes of ADHD. In some analyses, children who met modified criteria for the combined type had somewhat lower mathematics scores than comparison children. The robust academic deficits relative to intelligence in the inattentive group in this age range suggest either that inattention results in academic underachievement or that some children in the inattentive group have learning disabilities that cause secondary symptoms of inattention. Unexpectedly, wave 1 internalizing (anxiety and depression) symptoms independently predicted deficits in academic achievement controlling ADHD, intelligence, and other predictors.     

The link between statistical segmentation and word learning in adults

Many studies have shown that listeners can segment words from running speech based on conditional probabilities of syllable transitions, suggesting that this statistical learning could be a foundational component of language learning. However, few studies have shown a direct link between statistical segmentation and word learning. We examined this possible link in adults by following a statistical segmentation exposure phase with an artificial lexicon learning phase. Participants were able to learn all novel object-label pairings, but pairings were learned faster when labels contained high probability (word-like) or non-occurring syllable transitions from the statistical segmentation phase than when they contained low probability (boundary-straddling) syllable transitions. This suggests that, for adults, labels inconsistent with expectations based on statistical learning are harder to learn than consistent or neutral labels. In contrast, a previous study found that infants learn consistent labels, but not inconsistent or neutral labels.     

Contextual control of slot-machine gambling: replication and extension

Participants were trained and tested to select stimuli of differing physical quantities in the presence of 2 color contextual cues for more than and less than. Following more than and less than relational training, participants allocated the majority of their responses to the slot machine that shared formal properties of color with the contextual cue for more than, despite the identical payout probabilities of the slot machines.     

Effects of psychosocial and situational variables on substance abuse among homeless adults

Finding direct and indirect influences of salient psychosocial and situational variables on problem substance use among homeless people is important in designing evidence-based, effective, and relevant interventions for this special population. A stress-coping paradigm in conjunction with situational items specialized for homeless people was used to explore predictive relationships in a sample of homeless adults (N = 664) among (a) psychosocial variables of self-esteem, social support, positive and negative coping, and emotional distress, (b) situational variables of homelessness history and quality of recent housing, and (c) outcomes of alcohol use, injection drug use (IDU), and non-IDU. Lower self-esteem predicted greater emotional distress, lower positive coping, greater negative coping, and more alcohol use. Social support predicted less emotional distress and more positive coping. Chronic homelessness predicted more emotional distress, less positive coping, greater alcohol use, and IDU. Poor housing was associated with more alcohol use and IDU. Substance abuse interventions among the homeless should have a dual focus that includes attention to psychological issues and negative coping patterns while also addressing situational, environmental factors, including encouraging provision of permanent supportive housing.     

The roles of respect for parental authority and parenting practices in parent-child conflict among African American, Latino, and European American families

In this study, the authors examined whether parent-child conflict during the middle childhood years varied among families characterized as having different cultural traditions regarding issues of respect for parental authority and parenting practices. The sample included 133 African American, European American, and Latina girls (M age = 8.41 years) and their mothers. African American and Latina girls showed significantly more respect for parental authority than did European American girls. Furthermore, African American and Latina mothers reported significantly more intense arguments when respect was low than did European American mothers. Higher levels of discipline and better communication by mothers were both associated with reports of lower frequency of conflict; ethnicity did not moderate this association. Thus, respect for authority was most salient to group differences in conflict.