Derived stimulus relations and their role in a behavior-analytic account of human language and cognition

This article describes how the study of derived stimulus relations has provided the basis for a behavior-analytic approach to the study of human language and cognition in purely functional-analytic terms, with a focus on basic rather than applied research. The article begins with a brief history of the early behavior-analytic approach to human language and cognition, focusing on Skinner's (1957) text Verbal Behavior, his subsequent introduction of the concept of instructional control (Skinner, 1966), and Sidman's (1994) seminal research on stimulus equivalence relations. The article then considers how the concept of derived stimulus relations, as conceptualized within relational frame theory (Hayes et al., 2001), allowed researchers to refine and extend the functional approach to language and cognition in multiple ways. Finally, the article considers some recent conceptual and empirical developments that highlight how the concept of derived stimulus relations continues to play a key role in the behavior-analytic study of human language and cognition, particularly implicit cognition. In general, the article aims to provide a particular perspective on how the study of derived stimulus relations has facilitated and enhanced the behavior analysis of human language and cognition, particularly over the past 25-30 years

Functional map of arrestin binding to phosphorylated opsin, with and without agonist

Arrestins desensitize G protein-coupled receptors (GPCRs) and act as mediators of signalling. Here we investigated the interactions of arrestin-1 with two functionally distinct forms of the dim-light photoreceptor rhodopsin. Using unbiased scanning mutagenesis we probed the individual contribution of each arrestin residue to the interaction with the phosphorylated apo-receptor (Ops-P) and the agonist-bound form (Meta II-P). Disruption of the polar core or displacement of the C-tail strengthened binding to both receptor forms. In contrast, mutations of phosphate-binding residues (phosphosensors) suggest the phosphorylated receptor C-terminus binds arrestin differently for Meta II-P and Ops-P. Likewise, mutations within the inter-domain interface, variations in the receptor-binding loops and the C-edge of arrestin reveal different binding modes. In summary, our results indicate that arrestin-1 binding to Meta II-P and Ops-P is similarly dependent on arrestin activation, although the complexes formed with these two receptor forms are structurally distinct

Ziram, a pesticide associated with increased risk for Parkinson's disease, differentially affects the presynaptic function of aminergic and glutamatergic nerve terminals at the Drosophila neuromuscular junction

Multiple populations of aminergic neurons are affected in Parkinson's disease (PD), with serotonergic and noradrenergic loci responsible for some non-motor symptoms. Environmental toxins, such as the dithiocarbamate fungicide ziram, significantly increase the risk of developing PD and the attendant spectrum of both motor and non-motor symptoms. The mechanisms by which ziram and other environmental toxins increase the risk of PD, and the potential effects of these toxins on aminergic neurons, remain unclear. To determine the relative effects of ziram on the synaptic function of aminergic versus non-aminergic neurons, we used live-imaging at the Drosophila melanogaster larval neuromuscular junction (NMJ). In contrast to nearly all other studies of this model synapse, we imaged presynaptic function at both glutamatergic Type Ib and aminergic Type II boutons, the latter responsible for storage and release of octopamine, the invertebrate equivalent of noradrenalin. To quantify the kinetics of exo- and endo- cytosis, we employed an acid-sensitive form of GFP fused to the Drosophila vesicular monoamine transporter (DVMAT-pHluorin). Additional genetic probes were used to visualize intracellular calcium flux (GCaMP) and voltage changes (ArcLight). We find that at glutamatergic Type Ib terminals, exposure to ziram increases exocytosis and inhibits endocytosis. By contrast, at octopaminergic Type II terminals, ziram has no detectable effect on exocytosis and dramatically inhibits endocytosis. In contrast to other reports on the neuronal effects of ziram, these effects do not appear to result from perturbation of the UPS or calcium homeostasis. Unexpectedly, ziram also caused spontaneous and synchronized bursts of calcium influx (measured by GCaMP) and electrical activity (measured by ArcLight) at aminergic Type II, but not glutamatergic Type Ib, nerve terminals. These events are sensitive to both tetrodotoxin and cadmium chloride, and thus appear to represent spontaneous depolarizations followed by calcium influx into Type II terminals. We speculate that the differential effects of ziram on Type II versus Type Ib terminals may be relevant to the specific sensitivity of aminergic neurons in PD, and suggest that changes neuronal excitability could contribute to the increased risk for PD caused by exposure to ziram. We also suggest that the fly NMJ will be useful to explore the synaptic effects of other pesticides associated with an increased risk of PD

Reducing the Individual, Institutional and Societal Harms from Student Drug Use

[EN] Drug use among higher education students can cause harm to the individual, their institution, and the wider society. Academic performance, physical and mental health, institutional reputation, crime and unemployment can all be impacted by student drug use. Tackling this is a challenge, and is often compounded by limited student health and counselling capacity and the student’s reluctance or unwillingness to seek support. Digital brief interventions have shown promise in reducing harm from substance use, and provide an opportunity to meet students where they are, delivering always-on, confidential support and intervention. However, limited interventions for drug use are available for students, and many struggle with engagement and retention. Our team have developed a novel brief intervention, using best practices in digital intervention development, and behavioural change to overcome some of these challenges. We describe the development of our intervention and discuss how implementation could result in tangible benefits to the individual, institution, and society.Dick, S.; Dillon, B.; Vasiliou, V.; Davoren, M.; Dockray, S.; Heavin, C.; Linehan, C.... (2021). Reducing the Individual, Institutional and Societal Harms from Student Drug Use. En 7th International Conference on Higher Education Advances (HEAd'21). Editorial Universitat Politècnica de València. 465-472. https://doi.org/10.4995/HEAd21.2021.13060OCS46547

The Design of a Digital Behaviour Change Intervention for Third-Level Student Illicit Substance Use: A Persona Building Approach

Illicit substance use among third-level students is an issue of increasing concern. Digital behavioural change interventions have been developed to target this population, but reports of their effectiveness are mixed. The importance of end-user involvement in digital intervention development has been well established, but it appears that many interventions in this area did not engage end-users during development. This absence may have affected engagement, undermining their potential effectiveness. This paper describes the process and contributions of a persona-building approach in the development of a digital behaviour change intervention tailored to the needs of third-level students. Nine exploratory persona-building workshops were carried out with 31 students, and 7 project team members to develop personas for heavy, occasional and non-substance using third-level students. Early analysis has identified five archetypes which will contribute to the design of an acceptable and user-friendly intervention, and to the identification of targeted behavioural change techniques