Cognitive deficits of executive functions and decision‐making in obsessive‐compulsive disorder

The nature of cognitive deficits in obsessive‐compulsive disorder (OCD) is characterized by contradictory findings in terms of specific neuropsychological deficits. Selective impairments have been suggested to involve visuospatial memory, set shifting, decision‐making and response inhibition. The aim of this study was to investigate cognitive deficits in decision‐making and executive functioning in OCD. It was hypothesized that the OCD patients would be less accurate in their responses compared to the healthy controls in rational decision‐making on a version of the Cambridge gambling task (CGT) and on the color‐word interference test and on a version of the Tower of Hanoi test (tower test) of executive functioning. Thirteen participants with OCD were compared to a group of healthy controls (n = 13) matched for age, gender, education and verbal IQ. Results revealed significant differences between the OCD group and the healthy control group on quality of decision‐making on the CGT and for achievement score on the tower test. On these two tasks the OCD group performed worse than the healthy control group. The symptom‐dimension analysis revealed performance differences where safety checking patients were impaired on the tower test compared to contamination patients. Results are discussed in the framework of cognition and emotion processing and findings implicate that OCD models should address, specifically, the interaction between cognition and emotion. Here the emotional disruption hypothesis is forwarded to account for the dysfunctional behaviors in OCD. Further implications regarding methodological and inhibitory factors affecting cognitive information processing are highlighted.     

Self-determination and functional persuasion to encourage physical activity

This research advances a novel approach to promoting physical activity, based on the principle of functional matching in persuasion, and the self-concordance (SC) of people's motivations for physical activity. We propose that SC establishes a positive or negative orientation toward the challenge inherent in physical activity, and that the maximum yield of participation will be achieved by communications that appeal to each orientation. In two studies, we compared how messages emphasizing challenge versus available social support would influence recipients’ self-reported practices of physical activity and attitudes toward a physical activity setting. As hypothesized, these messages had differential effects for recipients whose pursuit of physical activity varied in SC, such that favorable outcomes were more reliably associated with challenge-oriented messages among respondents higher in SC versus support-oriented messages among respondents lower in SC. The findings suggest the merits of using self-regulatory, compared with object- or personality-based, constructs and measures to indicate psychological functions of ongoing health-related behaviors.     

The Contribution of Executive Skills to Reading Comprehension

Although word recognition deficits (WRD) are a known cause of reading comprehension deficits (RCD), other contributions to RCD, including executive function (EF), have not been fully explored. We examined the contribution of EF (working memory and planning), along with attention, decoding, fluency, and vocabulary to reading comprehension in 60 children (including 16 WRD and 10 RCD), ages 9–15 years. After controlling for commonly accepted contributors to reading comprehension (i.e., attention, decoding skills, fluency, and vocabulary), EF continued to make a significant contribution to reading comprehension but not to word recognition skills. These findings highlight the need for consideration of the role of EF in RCD.     

Health numeracy and cognitive decline in advanced age

ABSTRACT

The study aimed at investigating health numeracy in cognitively well performing healthy participants aged from 50 to 95 years as well as in participants with cognitive impairment, but no dementia (CIND). In cognitively well performing participants (n = 401), demographic variables and cognitive abilities (executive functions, reading comprehension, mental calculation, vocabulary) were associated with health numeracy. Older age, lower education, female gender as well as lower cognitive functions predicted low health numeracy. The effect of older age was partly mediated by executive functions and calculation abilities. Participants with CIND (n = 51) performed significantly lower than healthy controls in health numeracy. The findings suggest that cognitively well performing old individuals have difficulties in understanding health-related numerical information. The risk of misunderstanding health-related numerical information is increased in persons with CIND. As these population groups are frequently involved in health care decisions, particular attention has to be paid to providing numerical information in comprehensible form.     

School enrolment and executive functioning: A longitudinal perspective on developmental changes,the influence of learning context,and the prediction of pre-academic skills

The present two-year longitudinal study addressed developmental changes in different aspects of executive functioning (i.e., inhibition, updating, and cognitive flexibility) in a sample of 264 children aged between 5 and 7 years. Of special interest were issues of developmental progression over time, the influence of learning context and the predictive power of executive functions and school context for emerging academic skills. The results revealed pronounced improvements in all executive measures, both over time and as a function of age. For the learning context, small and age-dependent effects on executive skills were found. Inhibition uniquely contributed to the prediction of aspects of emerging academic skills, over and above chronological age and language skills.     

Impaired task switching performance in children with dyslexia but not in children with autism

Problems with cognitive control in both autism and dyslexia have already been reported in different studies. The present study specifically examined task-switching performance in children with autism and dyslexia. For this purpose, a multiple-trial paradigm was used with cues for colour- and shape-matching tasks presented before a run of trials. The cue could imply a task switch (when the cue changed the task) or a task repetition (when the cue did not change the task). Both reaction times and error rates were measured for switching, restarting, and general task performance. Participants were children with autism (24) and with dyslexia (25) and healthy controls (27) with normal IQ and ages from 12 to 18 years. The main finding was that while similar switching performance was observed between children with autism and the healthy controls, children with dyslexia showed a significant switch-specific delay relative to both healthy controls and children with autism. Furthermore, no deficit in restarting performance was observed for any of the two patient groups. Finally, additional evidence is provided for a more general deficit in information processing in dyslexia. Our data suggest that children with autism are able to switch between tasks in a similar way as do normally developing children as long as the tasks are unambiguously specified. Furthermore, the data imply switch-specific deficits in dyslexia additionally to the deficits in general information processing already reported in the literature. The implications of our data are further discussed in relation to the interpretation of the Wisconsin Card Sorting Test.     

Understanding the role of executive control in the Implicit Association Test: Why flexible people have small IAT effects

The goal of the present research was to investigate the role of three central-executive functions—switching of mental sets, inhibition of prepotent responses, and simultaneous storage and processing (i.e., working-memory capacity)—in accounting for method variance in the Implicit Association Test (IAT). In two studies, several IATs with unrelated contents were administered along with a battery of central-executive tasks, with multiple tasks tapping each of the above executive functions. Method variance was found to be related to the switching factor, but not to the inhibition factor. There was also evidence for a small independent contribution of the working-memory capacity factor. The findings constrain process accounts of the IAT, lending support to an account in terms of task-set switching, and they have consequences for applications.     

Variation in verbal fluency: A latent variable analysis of clustering,switching, and overall performance

Verbal fluency tasks have long been used to assess and estimate group and individual differences in executive functioning in both cognitive and neuropsychological research domains. Despite their ubiquity, however, the specific component processes important for success in these tasks have remained elusive. The current work sought to reveal these various components and their respective roles in determining performance in fluency tasks using latent variable analysis. Two types of verbal fluency (semantic and letter) were compared along with several cognitive constructs of interest (working memory capacity, inhibition, vocabulary size, and processing speed) in order to determine which constructs are necessary for performance in these tasks. The results are discussed within the context of a two-stage cyclical search process in which participants first search for higher order categories and then search for specific items within these categories.     

Executive functioning profiles in elite volleyball athletes: Preliminary results by a sport-specific task switching protocol

Executive functions (EF) are crucial for the athletes’ success, and they are even more essential in open skill sports (e.g. volleyball and football). In these sports, due to continuously changing conditions, goal-directed behaviours need to be repeatedly adjusted and corrected. One of the most important EF is the ability to continuously switch between two different tasks being required in a random sequence. We used a task-switching protocol in elite volleyball athletes, usually playing different roles, with the aim of evaluating if each role is characterized by specific switching abilities. On the basis of the specific competences requested by the game, thirty-six elite volleyball athletes were assigned to three groups: Strikers, Defenders and Mixed. Each player completed a customized sport-specific task-switching paradigm. Data evidenced that each role has specific characteristics. In Reaction Times, the Strikers were the fastest to answer to stimuli, while the Defender group provided a worse performance, particularly when defensive actions, that probably require more cognitive elaboration, had to be processed. Different effects emerged by the Errors. In fact, the Mixed group, which was the one with more expertise, appeared to be more accurate in the responses.Although preliminary, these results showed a minimal degree of cognitive flexibility for highly specialized Strikers and a maximum level for Mixed, allowing thus to highlight specific profiles of athletes. Data observed indicate the possibility to develop a test assessing the executive domain during the recruitment in a team, revealing a useful tool for choosing the most suitable role.