MODIFICATION OF HUMAN GASTRIC ACID SECRETION WITH OPERANT-CONDITIONING PROCEDURES1

In an attempt to control gastric acid secretion with operant-conditioning techniques, four normal women were given visual feedback on gastric pH plus money reinforcers. When money was made dependent on increased secretion in a differential-reinforcement-of-high-rates schedule, the rate of secretion of three of the four subjects increased to three times baseline. When money was then made dependent on decreased secretion in a differential-reinforcement-of-other-behaviors schedule, the rate of secretion of these three subjects returned to baseline levels. Heart rate, respiratory frequency, abdominal electromyographic activity, and stomach motility (measured by the electrogastrogram method) were not consistently correlated with acid secretion across subjects, although individual subjects showed substantial correlations between acid secretion and one or more other physiological response.     

A Patient-Tailored Evidence-Based Approach for Developing Early Neuropsychological Training Programs in Addiction Settings

Neuropsychology Review - Substance use disorders (SUDs) are associated with impairments of cognitive functions, and cognitive training programs are thus rapidly developing in SUD treatment....     

Barriers and facilitators of physical activity and sport participation among young transgender adults who are medically transitioning

Background: Transgender people (those who feel incongruence between the gender they were assigned at birth and their gender identity) engage in lower levels of physical activity compared to cisgender (non-transgender) people. Several factors have been shown to affect physical activity engagement in the cisgender population; however, the physical activity experiences of young transgender adults have not been explored. It is therefore the aim of the current study to understand what factors are associated with physical activity and sport engagement in young transgender adults who are medically transitioning.

Method: Semi-structured interviews were conducted with 14 young transgender adults (18–36 years) who had initiated their medical transition at a transgender health service in the United Kingdom. The data were analyzed using thematic analysis.

Results: Two main themes were identified: (1) barriers and (2) facilitators to physical activity and sport. Overall, the young transgender adults were insufficiently active due to inadequate changing facilities, body dissatisfaction, fears surrounding “passing” and not being accepted by others. At the same time, participants were motivated to engage in physical activity to increase their body satisfaction and gender congruence. However, participants felt there was a lack of safe and comfortable spaces to engage in physical activity and sport.

Conclusion: Young transgender adults who are medically transitioning experience several barriers to physical activity and sport, despite being motivated to be physically active. Initiatives to facilitate young transgender adults' ability to put their motivations into practice (i.e. to be more physically active) are needed.     

Engaging with research ethics in central Francophone Africa: reflections on a workshop about ancillary care

ABSTRACT: Research ethics is predominantly taught and practiced in Anglophone countries, particularly those in North America and Western Europe. Initiatives to build research ethics capacity in developing countries must attempt to avoid imposing foreign frameworks and engage with ethical issues in research that are locally relevant. This article describes the process and outcomes of a capacity-building workshop that took place in Kinshasa, Democratic Republic of Congo in the summer of 2011. Although the workshop focused on a specific ethical theme - the responsibilities of researchers to provide health-related care to their research participants - we argue that the structure of the workshop offers a useful method for engaging with research ethics in general, and the theme of ancillary care encourages a broad perspective on research ethics that is highly pertinent in low-income countries. The workshop follows an interactive, locally driven model that could be fruitfully replicated in similar settings.     

Missing data imputation and corrected statistics for large-scale behavioral databases

This article presents a new methodology for solving problems resulting from missing data in large-scale item performance behavioral databases. Useful statistics corrected for missing data are described, and a new method of imputation for missing data is proposed. This methodology is applied to the Dutch Lexicon Project database recently published by Keuleers, Diependaele, and Brysbaert (Frontiers in Psychology, 1, 174, 2010), which allows us to conclude that this database fulfills the conditions of use of the method recently proposed by Courrieu, Brand-D’Abrescia, Peereman, Spieler, and Rey (2011) for testing item performance models. Two application programs in MATLAB code are provided for the imputation of missing data in databases and for the computation of corrected statistics to test models.     

Stimulus complexity and prospective timing: clues for a parallel process model of time perception

Whereas many studies have considered the role of attention in prospective timing, fewer have established relations between movement complexity and prospective timing. The present study aims at assessing to what extent motion complexity interferes with prospective timing and at delineating a neuropsychophysical plausible model. We have thus designed a visual paradigm presenting stimuli in sequential pairs (reference comparison interval). Stimuli are motionless or moving according to different complexities, and stimulus complexities are intermixed within each pair. To prevent a possible attention-sharing effect, no concurrent task was required. Our study suggests that movement complexity is a key component of duration perception, and that the relative judgement of durations depends on spatio-temporal features of stimuli. In particular, it shows that movement complexity can bias subjects’ perception and performance, and that subjects detect that comparison intervals are longer than reference before their end. In the discussion, we advocate that the classical internal clock model cannot easily account for our results. Consequently, we propose a model for time perception, based on a parallel processing between comparison interval perception and the reconstruction of the reference duration.     

Is the influence of working memory capacity on high-level cognition mediated by complexity or resource-dependent elementary processes?

The aim of this study was to investigate the involvement of working memory (WM) in elementary activities and the nature of the mechanisms mediating the influence of WM capacity on high-level cognition. We demonstrate that even elementary activities such as reading digits, subitizing small arrays of dots, or solving simple additions like 3+1 are sensitive to individual differences in WM capacity. Moreover, we demonstrate that a complex task such as counting large arrays of dots involving these elementary activities as processing steps does not induce WM-related differences beyond what can be predicted from the concatenation of differences elicited by the task’s elementary constituents. In line with the time-based resource-sharing model, these results suggest that the influence of WM capacity on high-level cognition is mediated by the impact of a basic general-purpose resource that affects each atomic step of cognition.