Interhemispheric transfer in schizophrenics, depressives, and normals with schizoid tendencies

Although several studies suggest that schizophrenics suffer from an impairment in the interhemispheric transfer (IHT) of information, methodological weaknesses in these studies preclude clear interpretation of their results. This study addresses these criticisms in order to provide a clearer test of the IHT theory. Schizophrenics, depressives, normal controls, and normals with schizoid tendencies were assessed on five measures of IHT (verbal and nonverbal dichotic listening, intermanual transfer, bimanual block design, finger sequence repetition) and two measures of unilateral hemispheric processing (lateral eye movements, auditory thresholds). Results consistently failed to support an IHT deficit interpretation of schizophrenia. Schizoid normals had a significantly greater right-ear advantage on verbal dichotic listening than both psychiatric groups, a result suggesting enhanced left-hemisphere activation in schizoid normals. It is concluded that the IHT theory requires stronger empirical substantiation than has been obtained to date to warrant further consideration as a central theory of schizophrenia.     

A cognitive-behavioural analysis of mental toughness in national rugby league football teams

This study examined the relations between demographic characteristics of rugby players and selected aspects of psychological performance in rugby league football. Mental toughness was assessed using Psychological Performance Inventory and Hardiness on the Personal Views Survey III-R. Participants (N=70) were international rugby league footballers representing four teams (Wales, France, Ireland, England) in the 2000 Rugby League World Cup. Participants completed the questionnaires in training camp. Welsh-nationality players had a significantly higher mean score on two of the hardiness subscales. Hardiness measures displayed the greatest and most frequently statistically significant differences. The findings concur with previous work indicating superior hardiness is related to improved performance in sports.     

Facial memory deficits in children with fetal alcohol spectrum disorders

Prenatal exposure to alcohol may lead to a range of neurobehavioral effects, including impaired learning and memory. Although children with fetal alcohol spectrum disorders (FASD) exhibit both verbal and nonverbal memory impairments, their memory for faces has not been as thoroughly investigated and the extent literature provides inconsistent results. The aim of the current study was to determine whether difficulties in face memory exist in children with FASD and whether the difficulties are mediated by task demands. To address this, we used two measures of immediate and delayed facial recognition memory, the Children's Memory Scale (CMS) and Test of Memory and Learning (TOMAL). Compared to typically developing controls, children with FASD showed memory deficits on all tests and were more likely to perform in a clinically significant range. As well, children performed more poorly on the CMS compared to TOMAL, a finding consistent with the greater difficulty of the CMS task. Our results are consistent with our hypothesis that children with FASD show impairment in facial memory, particularly on demanding memory tasks.     

Re-exposure to studied items at test does not influence false recognition

In two experiments, we investigated whether re-exposure to previously studied items at test affects false recognition in the DRM paradigm. Furthermore, we examined whether exposure to the critical lure at test influences memory for subsequently presented study items. In Experiment 1, immediately following each studied DRM list, participants were given a recognition test. The tests were constructed such that the number of studied items preceding the critical lure varied from zero to five. Neither false recognition for critical lures nor accurate memory for studied items was affected by this manipulation. In Experiment 2, we replicated this pattern of results under speeded conditions at test. Both experiments confirm that exposure to previously studied items at test does not affect true or false recognition in the DRM paradigm. This pattern strongly suggests that retrieval processes do not influence false recognition in the DRM paradigm.     

I'm sitting here feeling aphasic! A study of recurrent perseverative errors elicited in unimpaired speakers

In this study, the recurrent perseverative errors produced by 44 speakers without impairment were examined in picture naming and reading aloud tasks under a fast response deadline. The proportion of perseverative relative to non-perseverative errors was greater in picture naming, the more error-prone task, than in reading aloud. Additionally, although perseverative errors were less likely to be related to the target than non-perseverative errors, the overall distribution of perseverative and non-perseverative errors in each task was similar. It is concluded that the perseverative errors produced by the participants reflected both the degree and level at which language processing efficiency was reduced in each task. This is consistent with a more recent account of perseveration as a result of normally existing persistent activation overcoming weakened activation of a target at any level of language processing. These results are compared with recent studies of recurrent perseverative errors produced by people with aphasia in light of the cognitive neuropsychological assumption that speakers with and without impairment utilise a common language processing system.     

Weak and Strong Theories of Truth

A subtheory of the theory of self-referential truth known as FS is shown to be weak as a theory of truth but equivalent to full FS in its proof-theoretic strength.     

Evaluating the factor structure of the Psychological Performance Inventory

This study assesses the construct validity of a measure of mental toughness, Loehr's Psychological Performance Inventory. Performers (N = 408, 303 men, 105 women, M age = 24.0 yr., SD = 6.7) drawn from eight sports (artistic rollerskating, basketball, canoeing, golf, rugby league, rugby union, soccer, swimming), and competing at either international, national, county and provincial, or club and regional standards. They completed the 42-item Psychological Performance Inventory during training camps. Principal components analysis provided minimal support for the factor structure. Instead, the exploratory analysis yielded a 4-factor 14-item model (PPI-A). A single factor underlying mental toughness (G(MT)) was identified with higher-order exploratory factor analysis using the Schmid-Leiman procedure. Psychometric analysis of the model, using confirmatory analysis techniques, fitted the data well. Collectively satisfying absolute and incremental fit index benchmarks, the inventory possesses satisfactory psychometric properties, with adequate reliability and convergent and discriminant validity. The results lend preliminary support to the factorial validity and reliability of the model; however, further investigation of its stability is required before recommending practitioners use changes in scores as an index for evaluating effects of training in psychological skills.     

Shock-induced fighting (SIF): Psychopharmacological studies

Shock-induced fighting in rats is briefly reviewed and the role of catecholamine serotonin and cholinergic neuromodulation is discussed in terms of specific agonists or antagonists to each system. The balance of action on presynaptic and postsynaptic receptors as well as the interconnections among the various neuromodulating systems help to determine the ultimate behavioral outcome as a response to drugs.     

Hardiness commitment,gender, and age differentiate university academic performance

Background The increasing diversity of students, particularly in age, attending university has seen a concomitant interest in factors predicting academic success. Aims This 2‐year correlational study examined whether age, gender (demographic variables), and hardiness (cognitive/emotional variable) differentiate and predict university final degree grade point average (GPA) and final‐year dissertation mark. Sample Data are reported from a total of 134 university undergraduate students. Method Participants provided baseline data in questionnaires administered during the first week of their second year of undergraduate study and gave consent for their academic progress to be tracked. Final degree GPA and dissertation mark were the academic performance criteria. Results Mature‐age students achieved higher final degree GPA compared to young undergraduates. Female students significantly outperformed their male counterparts in each measured academic assessment criteria. Female students also reported a significantly higher mean score on hardiness commitment compared to male students. Commitment was the most significant positive correlate of academic achievement. Final degree GPA and dissertation mark were significantly predicted by commitment, and commitment and gender, respectively. Conclusions The findings have implications for universities targeting academic support services to maximize student scholastic potential. Future research should incorporate hardiness, gender, and age with other variables known to predict academic success.     

Re-exposure to studied items at test does not influence false recognition

In two experiments, we investigated whether re-exposure to previously studied items at test affects false recognition in the DRM paradigm. Furthermore, we examined whether exposure to the critical lure at test influences memory for subsequently presented study items. In Experiment 1, immediately following each studied DRM list, participants were given a recognition test. The tests were constructed such that the number of studied items preceding the critical lure varied from zero to five. Neither false recognition for critical lures nor accurate memory for studied items was affected by this manipulation. In Experiment 2, we replicated this pattern of results under speeded conditions at test. Both experiments confirm that exposure to previously studied items at test does not affect true or false recognition in the DRM paradigm. This pattern strongly suggests that retrieval processes do not influence false recognition in the DRM paradigm.