Effect of drugs on response-duration differentiation VII: response-force requirements

Rats were trained to press a lever for at least 1 s but for less than 1.3 s. The force required to press the lever was then increased or decreased by 10, 15, or 20 g. Increases in the force requirements for lever pressing decreased timing accuracy, but decreases in the force requirement had the opposite effect. Accuracy decreases at increasing force requirements were characterized by an increase in the relative frequency of responses that were too short to meet the reinforcement criterion. In contrast, increases in accuracy when the force requirements were decreased were characterized by increases in response durations that met the reinforcement criterion and decreases in the relative frequency of responses that were too short to produce the reinforcer. Phencyclidine (PCP) and methamphetamine produced dose-dependent decreases in accuracy that were associated primarily with increases in the relative frequency of short response durations, although methamphetamine also produced increases in long response durations at some doses. When the effects of PCP were determined with the force requirement increased by 10 g or decreased by 15 g, the cumulative response-duration distribution shifted toward even shorter response durations. When the effects of methamphetamine were determined with the force requirement on the lever increased by 10 g, the cumulative frequency distribution was shifted toward shorter response durations to about the same extent as it had been before force requirements increased; however, when the force required to press the lever was decreased by 15 g, these shifts toward shorter response durations almost completely disappeared. These results show that increases and decreases in the force requirements for lever pressing have different effects on the accuracy of temporal response differentiation.     

Drug discrimination under two concurrent fixed-interval fixed-interval schedules

Pigeons were trained to discriminate 5.0 mg/kg pentobarbital from saline under a two-key concurrent fixed-interval (FI) 100-s FI 200-s schedule of food presentation, and later tinder a concurrent FI 40-s FI 80-s schedule, in which the FI component with the shorter time requirement reinforced responding on one key after drug administration (pentobarbital-biased key) and on the other key after saline administration (saline-biased key). After responding stabilized under the concurrent FI 100-s FI 200-s schedule, pigeons earned an average of 66% (after pentobarbital) to 68% (after saline) of their reinforcers for responding under the FI 100-s component of the concurrent schedule. These birds made an average of 70% of their responses on both the pentobarbital-biased key after the training dose of pentobarbital and the saline-biased key after saline. After responding stabilized under the concurrent FI 40-s FI 80-s schedule, pigeons earned an average of 67% of their reinforcers for responding under the FI 40 component after both saline and the training dose of pentobarbital. These birds made an average of 75% of their responses on the pentobarbital-biased key after the training dose of pentobarbital, but only 55% of their responses on the saline-biased key after saline. In test sessions preceded by doses of pentobarbital, chlordiazepoxide, ethanol, phencyclidine, or methamphetamine, the dose-response curves were similar under these two concurrent schedules. Pentobarbital, chlordiazepoxide, and ethanol produced dose-dependent increases in responding on the pentobarbital-biased key as the doses increased. For some birds, at the highest doses of these drugs, the dose-response curve turned over. Increasing doses of phencyclidine produced increased responding on the pentobarbital-biased key in some, but not all, birds. After methamphetamine, responding was largely confined to the saline-biased key. These data show that pigeons can perform drug discriminations under concurrent schedules in which the reinforcement frequency under the schedule components differs only by a factor of two, and that when other drugs are substituted for the training drugs they produce dose-response curves similar to the curves produced by these drugs under other concurrent interval schedules.     

Local-global processing in early-onset schizophrenia: evidence for an impairment in shifting the spatial scale of attention

In this study we report the results of two experiments on visual attention conducted with patients with early-onset schizophrenia. These experiments investigated the effect of irrelevant spatial-scale information upon the processing of relevant spatial-scale information, and the ability to shift the spatial scale of attention, across consecutive trials, between different levels of the hierarchical stimulus. Twelve patients with early-onset schizophrenia and matched controls performed local-global tasks under: (1) directed attention conditions with a consistency manipulation and (2) divided-attention conditions. In the directed-attention paradigm, the early-onset patients exhibited the normal patterns of global advantage and interference, and were not unduly affected by the consistency manipulation. Under divided-attention conditions, however, the early-onset patients exhibited a local-processing deficit. The source of this local processing deficit lay in the prolonged reaction time to local targets, when these had been preceded by a global target, but not when preceded by a local target. These findings suggest an impaired ability to shift the spatial scale of attention from a global to a local spatial scale in early-onset schizophrenia.     

Test-Retest Measurement Invariance of Clinic Referred Children’s ADHD Symptoms

This study examined the test-retest measurement invariance of ratings of the ADHD symptoms. Mothers of a group of 217 clinic-referred children (boys?=?169, girls?=?49; age range?=?7 to 17 years) completed ratings of the ADHD symptoms presented in a modified version of the Strengths and Weaknesses of ADHD-Symptoms and Normal Behavior Scale (SWAN-M) twice, 12 months apart. Confirmatory factor analysis (CFA) of their ratings at both time points provided more support for the bifactor model of ADHD [orthogonal general and specific factors for inattention (IA) and hyperactivity/impulsivity (HI) symptoms] over the 2-factor oblique model (factors for inattention IA and HI symptoms). For the bifactor model, measurement invariance testing using multiple-group CFA indicated support for configural and full scalar test-retest invariance when the chi-square difference test was applied. For metric invariance, all but one symptom showed invariance. When the differences in approximate fit indices were applied, there was support for full measurement invariance (configural, metric and scalar). The findings indicate that observed scores (based on maternal ratings of the SWAM-M), twelve months apart, are comparable as they have the same measurement properties. Several practical, theoretical, research and clinical implications of the findings are discussed.     

Pigeons perform poorly on a midsession reversal task without rigid temporal regularity

Animals make surprising anticipatory and perseverative errors when faced with a midsession reversal of reinforcer contingencies on a choice task with highly predictable stimulus–time relationships. In the current study, we asked whether pigeons would anticipate changes in reinforcement when the reinforcer contingencies for each stimulus were not fixed in time. We compared the responses of pigeons on a simultaneous choice task when the initially correct stimulus was randomized or alternated across sessions. Pigeons showed more errors overall compared with the typical results of a standard midsession reversal procedure, and they did not show the typical anticipatory errors prior to the contingency reversal. Probe tests that manipulated the spacing between trials also suggested that timing of the session exerted little control of pigeons’ behavior. The temporal structure of the experimental session thus appears to be an important determinant for animals’ use of time in midsession reversal procedures.     

Areas of Interest as a Signal Detection Problem in Behavioral Eye‐Tracking Research

Decision researchers frequently analyze attention to individual objects to test hypotheses about underlying cognitive processes. Generally, fixations are assigned to objects using a method known as area of interest (AOI). Ideally, an AOI includes all fixations belonging to an object while fixations to other objects are excluded. Unfortunately, due to measurement inaccuracy and insufficient distance between objects, the distributions of fixations to objects may overlap, resulting in a signal detection problem. If the AOI is to include all fixations to an object, it will also likely include fixations belonging to other objects (false positives). In a survey, we find that many researchers report testing multiple AOI sizes when performing analyses, presumably trying to balance the proportion of true and false positive fixations. To test whether AOI size influences the measurement of object attention and conclusions drawn about cognitive processes, we reanalyze four published studies and conduct a fifth tailored to our purpose. We find that in studies in which we expected overlapping fixation distributions, analyses benefited from smaller AOI sizes (0° visual angle margin). In studies where we expected no overlap, analyses benefited from larger AOI sizes (>.5° visual angle margins). We conclude with a guideline for the use of AOIs in behavioral eye‐tracking research. Copyright © 2015 John Wiley & Sons, Ltd.     

Understanding Workaholism: Data Synthesis, Theoretical Critique, and Future Design Strategies

Workaholism involves a personal reluctance to disengage from work, which is evidenced by the tendency to work irrespective of external demands. While the term workaholism has been widely used by the public for over 30 years, scientists are only beginning to explore the behavior in depth. To date, most research has occurred on an ad hoc basis, emerging from a wide variety of paradigms without being explicitly linked to theory. The current article presents three methods for defining workaholism and a précis of relevant measures, then provides an integrated overview of research relating workaholism to individual well-being. Three models implicit in existing workaholism research (addiction, learning, and trait theory) are expounded and critiqued, and four new procedures for researching workaholism are suggested. Finally, an integrated, multidisciplinary approach is proposed as an essential element in encouraging rigorous debate and continued development of workaholism theory.     

Religion in the UK: An Overview of Equality Statistics and Evidence Gaps

Social survey data is essential to measuring equality, for the assessment of change over time, and to the evaluation of the impact of new policies. In this article we have identified and evaluated the statistical data and evidence on religion in the UK in relation to key policy areas, such as employment, housing, health, education, and criminal justice. For each data source, we consider definitions, data collection, coverage of issues, sample size, and data access. We examine the multi-faceted nature of religion and consider the links between religious and ethnic identities. We also outline models that can link religious identity to equality outcomes (and hence potentially allow the measurement of discrimination) and identify the evidence gaps. The UK has one of the most religiously diverse populations in the European Union, both in terms of diversity within Christianity and between different world religions. However, while religion is increasingly recognised, in both legal and policy terms, as an important equality issue, the data on the dynamics of religion in the UK are limited. The inclusion of a new question on religion in the 2001 Census in England, Scotland, and Wales is a major new source of data, but data are limited regarding the role and significance of religion in people's everyday lives, particularly among ethnic minority populations. It is clear that there is a need for a far more comprehensive and rounded approach to data on religion in the UK, which takes account of its multi-dimensional nature.