Rapid visual learning in the rat: Effects at the 5-HT 1a receptor subtype

The 5-hydroxytryptamine 1a (5-HT 1a ) receptor agonist 8-hydroxy-2-(di-n-propylamino) tetralin (8-OH-DPAT; 0.15 mg/kg) impaired rats' rapid visual learning on a computerized maze. This treatment also increased decision time (DT) but the learning impairment was not necessarily a side-effect of slower responding because, in this task, responses made at long DT are more accurate than those at short DT. The selective 5-HT 1a receptor antagonist WAY-100635 (0.3 mg/kg) was itself without effect on accuracy, but was effective in reversing effects of 8-OH-DPAT (on both accuracy and DT). Within problems (i.e., over the 40-60 trials of a single discrimination), performance was reduced by treatment with 8-OH-DPAT at all stages of learning. We conclude that this effect is mediated through the 5-HT 1a receptor site (rather than through some other serotonergic receptor site or non-specific mechanism) as it was reversible by treatment with WAY-100635. Although it could still arise from behaviourally non-specific effects, the performance deficit finds its best account in terms of the psychological processes necessary to visual learning. Its reversal with WAY-100635 offers support to the hypothesis that 5-HT 1a receptor antagonists could improve cognitive function, under conditions of pre-existing impairment due to overactive serotonergic inhibition, as is thought to occur in Alzheimer's disease.     

Parallels Between Action‐Object Mapping and Word‐Object Mapping in Young Children

Across a series of four experiments with 3‐ to 4‐year‐olds we demonstrate how cognitive mechanisms supporting noun learning extend to the mapping of actions to objects. In Experiment 1 (n = 61) the demonstration of a novel action led children to select a novel, rather than a familiar object. In Experiment 2 (n = 78) children exhibited long‐term retention of novel action‐object mappings and extended these actions to other category members. In Experiment 3 (n = 60) we showed that children formed an accurate sensorimotor record of the novel action. In Experiment 4 (n = 54) we demonstrate limits on the types of actions mapped to novel objects. Overall these data suggest that certain aspects of noun mapping share common processing with action mapping and support a domain‐general account of word learning.     

The reasonably prudent person,or me?

Abundant research concerning the role of the self in social judgment suggests that people have a strong tendency to evaluate others’ actions, preferences, and values with regard to their own. Reliance on self-standards contrasts with the legal standard of the reasonably prudent person (RPP) standard, which presumably represents the behavior of the average person in the community. In three studies that investigated judgments of harmful actions, we compared the influence of self-standards (“How likely would I behave in this manner?”) and RPP estimates (“How likely would the average, reasonable person in the community behave in this manner?”). In each study, self-standards influenced participants’ judgments of guilt and the acceptability of the defendant's actions more than did judgments about what a RPP would do. Studies 2a and 2b also investigated attitudinal differences in susceptibility to RPP consensus manipulations. Participants judged a target who committed murder in self-defense, and also projected their own hypothetical behavior in the scenario. When the manipulated RPP disapproved of the murder, the target was deemed more culpable, but only among participants who themselves were unwilling to commit the hypothetical act. Participants who expressed willingness to murder in self-defense were unaffected by RPP information, regardless of whether or not it was consistent with their own stance. Hence, RPP information at best exerted minimal influence on juridical judgments, and only among certain participants. Implications of these findings for legal applications of the RPP, and for the role of the self in social judgment, are discussed.     

Impulse control disorders in Parkinson’s disease: Predominant role of psychological determinants

Objectives: Impulse Control Disorders (ICDs) in Parkinson’s disease (PD) have previously almost exclusively been considered to result from anti-parkinsonian medication. However, this biomedical perspective has failed to achieve a full understanding of the phenomenon and it is argued that a failure to consider psychological factors is a critical omission.

Design: The present study examined the predictive relationship between ICDs in PD and a range of psychological measures, whilst controlling for a number of biomedical determinants.

Main outcome measures: One hundred participants with idiopathic PD completed questionnaires that assessed demographic and clinical characteristics, psychological measures and the presence of ICDs (QUIP-RS).

Results: Increased use of a ‘negative’ coping strategy, stronger illness identity, more emotional illness representations and stress were found to be significant predictors of ICDs, and different psychological predictors were associated with different ICDs. Medication was not found to predict ICDs in the presence of psychological factors, either when total treatment levels were considered or when agonist dose was considered alone.

Conclusions: This study provides the first quantitative evidence of a predominant predictive relationship between psychological factors and ICDs in PD. The results suggest that psychological interventions may have useful therapeutic role to play for ICDs in PD.     

Sad and happy emotion discrimination in music by children with cochlear implants

Children using cochlear implants (CIs) develop speech perception but have difficulty perceiving complex acoustic signals. Mode and tempo are the two components used to recognize emotion in music. Based on CI limitations, we hypothesized children using CIs would have impaired perception of mode cues relative to their normal hearing peers and would rely more heavily on tempo cues to distinguish happy from sad music. Study participants were children with 13 right CIs and 3 left CIs (M = 12.7, SD = 2.6 years) and 16 normal hearing peers. Participants judged 96 brief piano excerpts from the classical genre as happy or sad in a forced-choice task. Music was randomly presented with alterations of transposed mode, tempo, or both. When music was presented in original form, children using CIs discriminated between happy and sad music with accuracy well above chance levels (87.5%) but significantly below those with normal hearing (98%). The CI group primarily used tempo cues, whereas normal hearing children relied more on mode cues. Transposing both mode and tempo cues in the same musical excerpt obliterated cues to emotion for both groups. Children using CIs showed significantly slower response times across all conditions. Children using CIs use tempo cues to discriminate happy versus sad music reflecting a very different hearing strategy than their normal hearing peers. Slower reaction times by children using CIs indicate that they found the task more difficult and support the possibility that they require different strategies to process emotion in music than normal.     

Early Developmental Screening for Children in Foster Care

Limited data exist about the ideal timing of developmental screening for young children entering foster care, and current best practice recommends screening by 1 month into care to prioritize resources for evaluation. Therefore, we aimed to: (1) compare detection rates for potential developmental delay (DD) at foster care entry before and after implementation of a developmental screen and (2) examine accuracy of developmental screening when performed at entry and 1 month into care. Charts of 124 children <6 years evaluated for an initial foster care health assessment (IFCHA) were reviewed to determine baseline detection rates for potential DD. The Parents’ Evaluation of Developmental Status (PEDS) screening tool was then prospectively administered to 167 children <6 years during their IFCHA to determine detection rates. One month following the IFCHA, caregivers were re-contacted, and the screen was re-administered. Accuracy of the initial PEDS screen was compared to the 1 month PEDS screen by calculation of sensitivity and specificity. At baseline, potential DD was detected in 34 % of children at the IFCHA compared to 46 % after implementation of the PEDS (P = 0.041). Compared to the 1 month screen, the early screen had a sensitivity of 75 % and specificity of 88 %. Use of a developmental screening tool at foster care entry increased detection of potential DD, and the results remained consistent with screening 1 month later. These results support use of a developmental screen for children in foster care and suggest that screening be performed as early as possible to expedite necessary evaluations and referrals.