Concurrent schedules: Effects of time- and response-allocation constraints

Five pigeons were trained on concurrent variable-interval schedules arranged on two keys. In Part 1 of the experiment, the subjects responded under no constraints, and the ratios of reinforcers obtainable were varied over five levels. In Part 2, the conditions of the experiment were changed such that the time spent responding on the left key before a subsequent changeover to the right key determined the minimum time that must be spent responding on the right key before a changeover to the left key could occur. When the left key provided a higher reinforcer rate than the right key, this procedure ensured that the time allocated to the two keys was approximately equal. The data showed that such a time-allocation constraint only marginally constrained response allocation. In Part 3, the numbers of responses emitted on the left key before a changeover to the right key determined the minimum number of responses that had to be emitted on the right key before a changeover to the left key could occur. This response constraint completely constrained time allocation. These data are consistent with the view that response allocation is a fundamental process (and time allocation a derivative process), or that response and time allocation are independently controlled, in concurrent-schedule performance.     

Resting autonomic activity in adults who stutter and its association with self-reports of social anxiety

PurposeThe purpose of this study was to investigate resting autonomic activity in adults who stutter (AWS) compared to adults who do not stutter (ANS) and the relationship this has on self-reports of social anxiety.MethodsThirteen AWS and 15 ANS completed the Social Interaction Anxiety Scale (SIAS; Mattick & Clark, 1998) and Brief Fear of Negative Evaluation (BFNE; Leary, 1983). Following this, measures of skin conductance levels (i.e. index of sympathetic activity) and respiratory sinus arrhythmia (i.e. index of parasympathetic activity) were taken during a 5-minute resting, baseline period. Independent sample t tests were used to assess differences between groups on self-reports of anxiety (SIAS, BFNE) and resting autonomic levels (SCL, RSA). Separate multiple regression analyses were performed in order to assess the relationship between self-reports of anxiety and autonomic measures.ResultsResults showed significantly higher mean SCL and lower mean RSA levels in the AWS compared to the ANS at resting, baseline. Regression analysis showed that self-reports from the SIAS had a significant effect on RSA levels for the AWS but not the ANS. No significant effects were found for BFNE on RSA. Nor was there a significant effect from SIAS or BFNE on SCL levels for either group.ConclusionFindings suggest that resting RSA levels may be a physiological marker for social anxiety levels in adults who stutter.     

Stimulation cognitive chez les personnes âgées : effets d’une méthode de stimulation cognitive par les jeux sur les fonctions cognitives et l’estime de soi

The purpose of this study was to examine the effects of a cognitive stimulation program with games on scores to cognitive tests (processing speed, mental flexibility, working memory, inhibition) and how this program can benefit to a psycho-affective measure, self-esteem in older adults. Forty-eight participants over 60 years old took part in the experiment. They were divided into two groups: 1 group followed a program of cognitive stimulation using leisure activities with games and 1 control group in which people gathered every week. There were 8 sessions of cognitive stimulation using leisure activities like games, one-hour session a week. Measures have focused on speed of processing and executive functions (shifting, updating and inhibition). They have been evaluated before and after the training program. Results show that the cognitive stimulation program using leisure activities with games is effective on speed of processing, memory span, inhibition and self-esteem but shows no benefits on shifting and updating. These results indicate that it seems to be possible to enhance cognitive resources, inhibition and self-esteem using leisure activities with games as a tool for cognitive stimulation.     

The impact of demographics and nutritional status on cognitive functioning in an Iranian adults sample

This study investigated the impact of demographic variables and nutritional status on adult cognitive functioning using structural equation modeling. Demographic variables that were considered were height, weight and gender, whilst nutritional status was measured on the Nutrition Assessment Inventory (NAI). Cognitive functions, such as executive cognitive functions, cognitive flexibility, cognitive ability and cognitive vulnerability were measured using the Amsterdam Executive Function Inventory (AEFI), the Cognitive Flexibility Scale (CFS), the Cognitive Ability Questionnaire (CAQ), and the Dysfunctional Attitude Scale Form A-Revised (DAS-A-R) respectively. Findings indicated that ethnicity and weight variables contribute to 8.8% of the nutritional status variations observed. A SEM analysis showed that nutritional status has an impact on 13% on the measured cognitive abilities of adults. The effects of “healthy nutrition”, “use of complementary nutritients”, “coping with high fat foods”, and “high fat food assumption” subscales of the nutrition scale were found to play a role in cognitive ability. This study shows a fitted SEM for the predictive roles of ethnicity, weight and nutritional status on the cognitive ability in adults.     

Inhibitory control and set shifting describe different pathways from behavioral inhibition to socially anxious behavior

Individuals with a behaviorally inhibited (BI) temperament are more likely to develop social anxiety. However, the mechanisms by which socially anxious behavior emerges from BI are unclear. Variation in different forms of top‐down control, specifically executive functions (EF), may play distinct roles and characterize differential pathways to social anxiety. Here 291 children were assessed for BI in toddlerhood (ages 2 and 3), parent‐reported inhibitory control and set shifting during middle childhood (age 7), and multidimensional assessment of socially anxious behavior completed during late childhood and early adolescence (ages 9 and 12). Structural equation modeling revealed that early variation in BI predicted the development of socially anxious behavior through either higher levels of parent‐reported inhibitory control or lower levels of parent‐reported set shifting. These data reinforce the notion that top‐down control does not uniformly influence relations between temperament and socially anxious behavior. These data suggest novel approaches to thinking about the role of EFs and social anxiety outcomes as children approach adolescence.     

Toward ethical cognitive architectures for the development of artificial moral agents

New technologies based on artificial agents promise to change the next generation of autonomous systems and therefore our interaction with them. Systems based on artificial agents such as self-driving cars and social robots are examples of this technology that is seeking to improve the quality of people’s life. Cognitive architectures aim to create some of the most challenging artificial agents commonly known as bio-inspired cognitive agents. This type of artificial agent seeks to embody human-like intelligence in order to operate and solve problems in the real world as humans do. Moreover, some cognitive architectures such as Soar, LIDA, ACT-R, and iCub try to be fundamental architectures for the Artificial General Intelligence model of human cognition. Therefore, researchers in the machine ethics field face ethical questions related to what mechanisms an artificial agent must have for making moral decisions in order to ensure that their actions are always ethically right. This paper aims to identify some challenges that researchers need to solve in order to create ethical cognitive architectures. These cognitive architectures are characterized by the capacity to endow artificial agents with appropriate mechanisms to exhibit explicit ethical behavior. Additionally, we offer some reasons to develop ethical cognitive architectures. We hope that this study can be useful to guide future research on ethical cognitive architectures.     

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.     

Determination of a behavioral transfer function: White-noise analysis of session-to-session response-ratio dynamics on concurrent VI VI schedules

Six pigeons were exposed to concurrent variable-interval schedules in which the programmed reinforcer ratios changed from session to session according to a pseudorandom binary sequence. This procedure corresponded to the stochastic identification paradigm (“white-noise experiment”) of systems theory and enabled the relation between log response ratios in the current session and log reinforcer ratios in all previous sessions to be determined. Such dynamic relations are called linear transfer functions. Both nonparametric and parametric representations of these, in the form of “impulse-response functions,” were determined for each bird. The session-to-session response ratios resulting from the session-to-session pseudorandom binary variations in reinforcer ratios were well predicted by the impulse-response functions identified for each pigeon. The impulse-response functions were well fitted by a second-order dynamic model involving only two parameters: a time constant and a gain. The mean time constant was 0.67 sessions, implying that the effects of abrupt changes in log reinforcer ratios should be 96% complete within about five sessions. The mean gain was 0.53, which was surprisingly low inasmuch as it should equal the sensitivity to reinforcement ratio observed under steady-state conditions. The same six pigeons were subjected to a similar experiment 10 months following the first. Despite individual differences in impulse-response functions between birds within each experiment, the impulse-response functions determined from the two experiments were essentially the same.     

THE FUNCTIONS OF ASSESSMENT: IMPLICATIONS FOR SELECTION AND DEVELOPMENT OF DEVICES FOR ASSESSING REPERTOIRES IN CLINICAL,EDUCATIONAL, AND OTHER SETTINGS

An attempt is made to identify the many different functions that assessment of an individual's repertoire can serve. Implications of these functions for the character of and evidence about assessment devices are suggested. The functions fall into two general groups, those which influence decisions regarding an individual learner, and those which influence policy, program development, and scientific knowledge. The first group of functions is presented in a rough chronological sequence such that they form a “behavioral assessment funnel,” beginning with functions involving broad-band assessment to identify likely persons and skill areas, and narrowing to the precise pinpointing, monitoring, and follow-up functions. The contribution of behavior analysis and behavior therapy to assessment methodology in this sequence is identified as well as the areas where more traditionally conceived methods are still useful. The second group of functions and behavioral contributions to it are then discussed.