Modulation of N400 in chronic non-fluent aphasia using low frequency Repetitive Transcranial Magnetic Stimulation (rTMS)

Low frequency Repetitive Transcranial Magnetic Stimulation (rTMS) has previously been applied to language homologues in non-fluent populations of persons with aphasia yielding significant improvements in behavioral language function up to 43 months post stimulation. The present study aimed to investigate the electrophysiological correlates associated with the application of rTMS through measurement of the semantic based N400 Event-related brain potentials (ERP) component. Low frequency (1 Hz) rTMS was applied to the anterior portion of the homologue to Broca’s area (pars triangularis), for 20 min per day for 10 days, using a stereotactic neuronavigational system. Twelve non-fluent persons with aphasia, 2-6 years post stroke were stimulated. Six participants were randomly assigned to receive real stimulation and six participants were randomly assigned to receive a blind sham control condition. ERP measures were recorded at baseline, 1 week and 2 months subsequent to stimulation. The findings demonstrate treatment related changes observed in the stimulation group when compared to the placebo control group at 2 months post stimulation indicating neuromodulation of N400 as a result of rTMS. No treatment related changes were identified in the stimulation group, when compared to the sham group from baseline to 1 week post stimulation. The electrophysiological results represent the capacity of rTMS to modulate neural language networks and measures of lexical-semantic function in participants with non-fluent aphasia and suggest that time may be an important factor in brain reorganization subsequent to rTMS.     

Developmental Risk and Young Children’s Regulatory Strategies: Predicting Behavior Problems at Age Five

Children with early developmental delays are at heightened risk for behavior problems and comorbid psychopathology. This study examined the trajectories of regulatory capabilities and their potentially mediating role in the development of behavior problems for children with and without early developmental delays. A sample of 231 children comprised of 137 typically developing children and 94 children with developmental delays were examined during mildly frustrating laboratory tasks across the preschool period (ages 3–5). Results indicated that children with delays had greater use of maladaptive strategies (distraction, distress venting) and lower use of adaptive strategies (constructive coping) than typically developing children. For both groups, strategies had similar rates of growth across time; maladaptive strategies decreased and adaptive strategies increased. The intercept of strategy use, but not the slope, was found to mediate the relation between developmental risk and externalizing behaviors. Findings support that dysregulation, rather than the developmental risk, may be responsible for the high levels of comorbid psychopathology.     

Personality predicts innovation and social learning in children: Implications for cultural evolution

Innovation and social learning are the pillars of cultural evolution, allowing cultural behaviours to cumulatively advance over generations. Yet, little is known about individual differences in the use of social and asocial information. We examined whether personality influenced 7-11-year-old children's (N = 282) propensity to elect to observe others first or independently generate solutions to novel problems. Conscientiousness was associated with electing for no demonstrations, while agreeableness was associated with opting for demonstrations. For children receiving demonstrations, openness to experience consistently predicted deviation from observed methods. Children who opted for no demonstrations were also more likely than those opting for demonstrations to exhibit tool manufacture on an innovation challenge and displayed higher creativity, as measured by an alternate uses task. These results highlight how new cultural traditions emerge, establish and advance by identifying which individuals generate new cultural variants in populations and which are influential in the diffusion of these variants, and help reduce the apparent tension within the ‘ratchet’ of cumulative culture.     

The Mating Sociometer and Attractive Others: A Double-Edged Sword in Romantic Relationships

Eighty-one participants were recruited to test the sensitivity of the mating sociometer to mate-value feedback in the context of ongoing intimate relationships. Experiences of social rejection/acceptance by attractive opposite-sex confederates were manipulated. The effects of this manipulation on self-esteem, relationship satisfaction and commitment, perceptions of dating alternatives, and friendship-dedication were assessed. Social rejection/acceptance by members of the opposite sex altered relationship satisfaction and commitment; this causal link was amplified by changes in state self-esteem; and these effects were specific to intimate relationships and did not generalize to friendship-dedication. This research supports a domain-specific conceptualization of sociometer theory, extending the theory in important directions.     

Not by Labor Alone: Considerations for Value Influence Use of the Labor Rule in Ownership Transfers

People often assign ownership to the person who has invested labor into making an object (labor rule). However, labor usually improves objects and increases their value, and it has not been investigated whether these considerations underlie people's use of the labor rule. We presented participants with third‐party ownership conflicts between an owner of materials and an artist who used the materials for some artwork. Experiment 1 revealed that participants were more likely to transfer ownership to the artist for low‐value materials than for high‐value materials, and Experiment 2 showed that this effect was further moderated by the amount of effort the artist had invested. A third experiment confirmed that participants transferred ownership more often if the artist's labor had increased the value of the materials than when it had added no value. These findings suggest that considerations for value underlie ownership transfers following the investment of labor.     

Validity of the SF-12 in a Canadian Old Order Mennonite Community

To assess the validity of the Physical and Mental Component Summary scores (PCS-12 and MCS-12) of the SF-12 Health Survey (SF-12) in an Old Order Mennonite (OOM) community in Ontario, Canada. Most SF-12 validation studies have focused on general populations or clinical groups. This paper adds to the SF-12 literature by validating the instrument in a minority population. Sixty percent of the adult OOM population (n?=?1,171) completed a survey which had the SF-12 embedded within it. The survey also included questions on health determinants and the prevalence of chronic conditions. Factor analysis was used to confirm the two-factor structure of the SF-12. Item-scale correlations were calculated to assess convergent and discriminant validity. PCS-12 and MCS-12 variability by known subgroups were also explored. Factor analysis confirmed the two-factor structure and hypothesized loadings on the latent physical and mental health factors. Item-scale correlations demonstrated satisfactory convergent and discriminant validity. SF-12 summary scores distinguished well, and in the expected manner, between groups of respondents for gender, age, income adequacy, marital status, self-reported health measures, and other health determinants such as coping, trust, social interaction, and spirituality. PCS-12 and MCS-12 scores were lower in those with various chronic conditions compared to those without.The SF-12 appears to be a valid instrument for measuring health status in this minority population. Future SF-12 studies in OOMs and other populations may benefit from using Version 2 of the SF-12, where the dichotomous questions have been replaced by questions offering respondents more choice.     

Preserved implicit learning on both the serial reaction time task and artificial grammar in patients with Parkinson's disease

Thirteen nondemented patients with Parkinson's disease (PD) were compared with age-matched controls on two standard tests of implicit learning. A verbal version of the Serial Reaction Time (SRT) task was used to assess sequence learning and an artificial grammar (AG) task assessed perceptual learning. It was predicted that PD patients would show implicit learning on the AG task but not the SRT task, as motor sequence learning is thought to be reliant on the basal ganglia, which is damaged in PD. Patients with PD demonstrated implicit learning on both tasks. In light of these unexpected results the research on SRT learning in PD is reconsidered, and some possible explanations for the sometimes conflicting results of PD patient samples on the SRT task are considered. Four factors which merit further study in this regard are the degree to which the SRT task relies on overt motor responses, the effects of frontal lobe dysfunction upon implicit sequence learning, the effects of cerebellar degeneration, and the degree to which the illness itself has advanced.     

Reinforcer pathology,probabilistic choice,and medication adherence in patients with multiple sclerosis

The reinforcer pathology model posits that core behavioral economic mechanisms, including delay discounting and behavioral economic demand, underlie adverse health decisions and related clinical disorders. Extensions beyond substance use disorder and obesity, however, are limited. Using a reinforcer pathology framework, this study evaluates medical adherence decisions in patients with multiple sclerosis. Participants completed behavioral economic measures, including delay discounting, probability discounting, and a medication purchase task. A medical decision-making task was also used to evaluate how sensitivity to mild side effect risk and efficacy contributed to the likelihood of taking a hypothetical disease-modifying therapy. Less steep delay discounting and more intense (greater) medication demand were independently associated with greater adherence to the medication decision-making procedure. More generally, the pattern of interrelations between the medication-specific and general behavioral economic metrics was consistent with and contributes to the reinforcer pathology model. Additional research is warranted to expand these models to different populations and health behaviors, including those of a positive health orientation (i.e., medication adherence).