Temporal kinetics of prefrontal modulation of the extrastriate cortex during visual attention

Single-unit, event-related potential (ERP), and neuroimaging studies have implicated the prefrontal cortex (PFC) in top-down control of attention and working memory. We conducted an experiment in patients with unilateral PFC damage (n=8) to assess the temporal kinetics of PFC-extrastriate interactions during visual attention. Subjects alternated attention between the left and the right hemifields in successive runs while they detected target stimuli embedded in streams of repetitive task-irrelevant stimuli (standards). The design enabled us to examine tonic (spatial selection) and phasic (feature selection) PFC-extrastriate interactions. PFC damage impaired performance in the visual field contralateral to lesions, as manifested by both larger reaction times and error rates. Assessment of the extrastriate P1 ERP revealed that the PFC exerts a tonic (spatial selection) excitatory input to the ipsilateral extrastriate cortex as early as 100 msec post stimulus delivery. The PFC exerts a second phasic (feature selection) excitatory extrastriate modulation from 180 to 300 msec, as evidenced by reductions in selection negativity after damage. Finally, reductions of the N2 ERP to target stimuli supports the notion that the PFC exerts a third phasic (target selection) signal necessary for successful template matching during postselection analysis of target features. The results provide electrophysiological evidence of three distinct tonic and phasic PFC inputs to the extrastriate cortex in the initial few hundred milliseconds of stimulus processing. Damage to this network appears to underlie the pervasive deficits in attention observed in patients with prefrontal lesions.     

The influence of playing a non-reward game on motor ability and executive function in Parkinson's disease

The aim of this study is to evaluate the acute effect of playing games on executive function and motor ability in Parkinson's disease (PD). Consecutive cases with PD were studied with the Unified Parkinson Disease Rating Scale (UPDRS), Mini-Mental State examination (MMSE), Beck Depression Inventory (BDI), Stroop test, finger tapping and 14-meter walk test. After randomization, patients performed a game of dominoes and were tested before and after experiment being further categorized as control, winners or non-winners. Forty patients, 27 male (67.5%), aged 48 to 84 years (63.2 ± 8.5), Hoehn & Yahr I to III were included. Twenty-eight (70%) presented depressive symptoms (BDI > 10). Groups (Control N = 13; Winners = 14 and Non-winners = 13) were not different regarding age, disease duration, age at onset, BMI, MMSE scores, depressive symptoms, levodopa dose, and previous practice of games. Winners presented significantly better results on executive function (Stroop test, p = 0.002) and on motor activity (Finger tapping, p = 0.01). Non-winners showed a trend of better performance in the 14-meter-walk test. This study shows that the practice of a non-reward game acutely improved memory and motor skills in PD. Our results suggest a role for the reward system in the modulation of the dopaminergic function of the basal ganglia in these patients.     

Variables associated with the nature of sexual abuse to minors

This study analyzes the prevalence and characteristics of childhood and adolescence sexual abuse suffered by a sample of university students, as well as the variables associated with the nature of abuse. Participants anonymously completed the Questionnaire on Child Sexual Abuse, in order to obtain information about experience of sexual abuse. Of a total of 2,375 students, 289 (12.2%) declared having suffered sexual abuse before the age of 18. The invasiveness, continuity, and severity of abuse was related to the location where the abuse took place (the more severe cases were committed in the homes of the victim and perpetrator) and to the circumstances of abuse (relationships with partners/at a party or while caring for a child predicted more severe abuse). The age of the victim (preschool) and an intrafamilial relationship between victim and perpetrator were also related to more invasive, continuous, and severe sexual abuse. The knowledge of characteristics of perpetrator and victim and the context in which sexual abuse occurs can help to better comprehend the nature and correlates of sexual abuse. The results of the present study may contribute to the design of programs for the prevention of sexual abuse to minors.     

Career Adapt-Abilities Scale—Brazilian Form: Psychometric properties and relationships to personality

The Career Adapt-Abilities Scale—Brazilian Form (CAASBrazil) consists of four scales which measure concern, control, curiosity, and confidence as psychosocial resources for managing occupational transitions, developmental tasks, and work traumas. Internal consistency estimates for the subscale and total scores ranged from good to excellent. The factor structure was quite similar to the one computed for combined data from 13 countries. CAASBrazil is similar to the International Form, with the exception of two items that were not included in Brazilian version. Concurrent validity evidence was collected relative to personality factors from the Five-Factor Model of Personality. The relationships between career adaptability and personality factors were as predicted.     

Transitional and steady-state choice behavior under an adjusting-delay schedule

Twelve rats made repeated choices on an adjusting-delay schedule between a smaller reinforcer (A) that was delivered immediately after a response and a larger reinforcer (B) that was delivered after a delay which increased or decreased by 20% depending on the subject's choices in successive blocks of trials. In two phases of the experiment (100 sessions and 40 sessions), reinforcer sizes were selected which enabled theoretical parameters expressing the rate of delay discounting and sensitivity to reinforcer size to be estimated from the ratio of the indifference delays obtained in the two phases. Indifference delays, calculated from adjusting delays in the last 10 sessions of each phase, were shorter when the sizes of A and B were 14 and 25 μl of a 0.6 M sucrose solution than when they were 25 and 100 μl of the same solution. The ratio of the indifference delays was significantly smaller than that predicted on the basis of an assumed linear relation between reinforcer size and instantaneous reinforcer value, consistent with a previous proposal that this relation may be hyperbolic in form. Estimates of the rate of delay discounting based on the ratio of the two indifference delays (mean, 0.08 s(-1)) were similar to values obtained previously using different intertemporal choice protocols. Estimates of the size-sensitivity parameter (mean 113 μl) were similar to estimates recently derived from performance on progressive-ratio schedules. In both phases of the experiment, adjusting delays in successive blocks of trials were analyzed using the Fourier transform. The power spectrum obtained from individual rats had a dominant frequency that corresponded to a period of oscillation of the adjusting delay between 30 and 100 trial blocks (mean, 78). Power in the dominant frequency band was highest in the early sessions of the first phase and declined with extended training. It is suggested that this experimental protocol may have utility in neurobehavioral studies of intertemporal choice.     

The Quasi-lattice of Indiscernible Elements

The literature on quantum logic emphasizes that the algebraic structures involved with orthodox quantum mechanics are non distributive. In this paper we develop a particular algebraic structure, the quasi-lattice ( \mathfrakI{\mathfrak{I}}-lattice), which can be modeled by an algebraic structure built in quasi-set theory \mathfrakQ{\mathfrak{Q}} . This structure is non distributive and involve indiscernible elements. Thus we show that in taking into account indiscernibility as a primitive concept, the quasi-lattice that ‘naturally’ arises is non distributive.     

Interpersonal coordination and ball dynamics in futsal (indoor football)

Here, we report an investigation of the patterned movement behavior of players for a specific sub-phase of the game of futsal, namely when the goalkeeper for the attacking team is substituted with an extra outfield player. The movement trajectories of the ball and players were recorded in both lateral and longitudinal directions and investigated using relative phase analysis. Some differences in phase relations between different playing dyads were noted, indicating specificity of phase attractions, or otherwise, for certain players. In general terms, the defenders demonstrated strong in-phase attractions with the ball and with each other, whereas weaker phase attractions, indicated by increased relative phase variability, were observed for the attackers and ball, as well as between attackers themselves. These results demonstrate different coordination dynamics for the defending and attacking dyads, from which we interpret evidence for different playing sub-systems consistent with different team objectives linked together in an overarching game structure. In keeping with dynamical systems theory for complex systems, we view this sub-phase of futsal as being characterized by coordinated behavior patterns that emerge as a result of self-organizing processes. These dynamic patterns are generated within functional constraints, with players and teams exerting mutual influence on each other.     

A Comparison of the Taped Spelling Intervention and Cover,Copy, and Compare for Students with Learning Disabilities

This study evaluated the effectiveness and compared the efficiency of two interventions on the spelling performance of four fifth-grade students with learning disabilities in reading and writing. The first intervention, Cover, Copy, and Compare (CCC), is an established, evidence-based procedure, while the second, the Taped Spelling Intervention (TSI), is a new procedure with only one published article establishing its effectiveness at the time of this study. Although both interventions resulted in spelling performance gains, learning speed was higher in the CCC condition and students overwhelmingly reported preferences for CCC over TSI. Spelling gains were maintained on assessments administered approximately two weeks following the final intervention sessions for both interventions. Discussion focuses on the importance of easily implemented, socially acceptable, time- and resource-efficient interventions for increasing the academic performance of students, and the value of comparative analyses for choosing appropriate interventions.