Anne C. Macaskill

OPTIMAL AND NONOPTIMAL CHOICE IN A LABORATORY-BASED SUNK COST TASK WITH HUMANS: A CROSS-SPECIES REPLICATION

The current four experiments examined the sunk cost effect-nonoptimal persistence following investment-in a laboratory-based decision-making task with adult humans. Subjects made repeated decisions about whether to persist in a course of action-a fixed-ratio schedule whose response requirements varied unpredictably from one trial to the next-or to abandon it and escape in favor of a new trial with a potentially smaller fixed ratio schedule. Satisfying the ratio requirement produced a brief video clip from a preferred television program. In Experiment 1, sunk-cost errors were less likely in subjects who had previously experienced markedly differential reinforcement for escape. In Experiment 2, stimulus changes correlated with changes in mean response requirement, and these changes reduced sunk-cost errors in a small number of subjects. In Experiment 3, sunk-cost errors occurred more frequently as the ratio of the mean response requirements for persistence and escape approached 1.0. The importance of this variable was further supported by the results of Experiment 4, in which features other than this ratio did not markedly alter performance. These four experiments identified some key determinants of whether humans commit the sunk-cost error and confirmed the utility of video clips as reinforcers in experimental research with humans.

The disruptive effects of methamphetamine on delayed-matching-to-sample performance reflect proactive interference and are reduced by SCH23390

Different drugs produce different patterns of impairment on delayed matching-to-sample tasks. For example, (+/-)3,4-methylenedioxymethamphetamine (MDMA) produces an increase in proactive interference. That is, subjects are less accurate when they are required to make a response different to the one they made on the immediately previous trial. The current study assessed whether methamphetamine also produces this particular pattern of disruption in delayed matching-to-sample performance in rats. Methamphetamine primarily reduced accuracy on trials where the correct response differed from the one made on the previous trial. Thus methamphetamine, like MDMA and other stimulant-based drugs of abuse, increased proactive interference. This impairment was reduced by prior administration of the dopamine D1 antagonist SCH23390. These results further extend a general conclusion that a range of stimulant-based drugs may disrupt working memory function indirectly via a tendency to repeat previously made responses and that this disruption is related to D1 receptor activity.

Prevention of the development of problem behavior: A laboratory model

Few studies have isolated the preventive efficacy of common behavioral strategies like noncontingent reinforcement (NCR) and differential reinforcement of alternative behavior (DRA). The purpose of the current study was to develop and evaluate a laboratory model of these two problem behavior prevention strategies. Undergraduate students participated in a computer simulation, in which clicks to a designated area of the computer screen were analogous to the emergence of problem behavior. The responding of participants in a control group, who experienced a percentile schedule used to mimic the shaping of problem behavior, was compared to that of participants in two experimental groups, each with a history of either DRA or NCR. Between-subjects group comparisons showed that both intervention strategies were equally effective in the prevention of our analog to problem behavior when compared to the control group. The strengths and limitations of a laboratory model for prevention are discussed in light of recent applied work in this area.

Student Responses to Active Learning Activities with Live and Virtual Rats in Psychology Teaching Laboratories.

Taking an ethical approach to using nonhuman animals in teaching requires assessment of the learning benefits of using animals and how these compare to the benefits of alternative teaching practices. It is also important to consider whether students have ethical reservations about completing exercises with animals. We compared upper level undergraduate students’ evaluations of psychology laboratories using live rats with their evaluations of using a virtual rat (Sniffy). Students reported that the live-rat labs were ethically acceptable and that working with live rats enhanced their learning to a greater extent than working with Sniffy. These results support the retention of laboratories using live rats in psychology courses.

Realistic Free-Spins Features Increase Preference for Slot Machines

Despite increasing research into how the structural characteristics of slot machines influence gambling behaviour there have been no experimental investigations into the effect of free-spins bonus features—a structural characteristic that is commonly central to the design of slot machines. This series of three experiments investigated the free-spins feature using slot machine simulations to determine whether participants allocate more wagers to a machine with free spins, and, which components of free-spins features drive this preference. In each experiment, participants were exposed to two computer-simulated slot machines—one with a free-spins feature or similar bonus feature and one without. Participants then completed a testing phase where they could freely switch between the two machines. In Experiment 1, participants did not prefer the machine with a simple free-spins feature. In Experiment 2 the free-spins feature incorporated additional elements such as sounds, animations, and an increased win frequency; participants preferred to gamble on this machine. The Experiment 3 “bonus feature” machine resembled the free spins machine in Experiment 2 except spins were not free; participants showed a clear preference for this machine also. These findings indicate that (1) free-spins features have a major influence over machine choice and (2) the “freeness” of the free-spins bonus features is not an important driver of preference, contrary to self-report and interview research with gamblers.

The effect of MDMA on sensitivity to reinforcement rate.

Administration of (±)3,4-methylenedioxymethamphetamine (MDMA) causes memory errors by increasing proactive interference. This might occur because MDMA alters sensitivity to reinforcement. The current 2 experiments investigated this directly by assessing the acute (Experiment 1) and chronic (Experiment 2) effects of MDMA on sensitivity to reinforcement. We presented 5 pairs of concurrent variable interval schedules within each session and calculated sensitivity to reinforcement for 3 acute doses of MDMA. In contrast to the related drug, d-amphetamine, and in spite of producing reductions in response rate, MDMA did not reduce sensitivity to reinforcement rate. Chronic administration of a fixed dose of MDMA following each session reduced response rate but did not affect sensitivity to reinforcement rate. In combination with previous research, these results indicate that related drugs may have different effects on sensitivity to reinforcement and that these effects should be considered when interpreting disruptions to operant task performance caused by drug administration. (PsycINFO Database Record

Developing a pan-university professional learning community

Abstract Professional learning communities (PLCs) support students’ learning in pre-tertiary education, but have not been sufficiently explored at the tertiary level. Drawing on the literature on PLCs across broader educational contexts, we explore the development of a PLC within our University using analysis of survey responses and through document analyses. Key themes from our data collectively reveal the core features of our evolving PLC – Building community; Ground-up design; Creating a safe space – and demonstrate both the broader impacts of the community and the on-going challenges faced as we seek to develop a sustainable PLC. Recommendations for academic developers interested in the development of PLCs within their contexts are offered.

Derived relations and the slot machine near-win effect

Abstract The current study investigated whether verbal processes underlie preferences for slot machines that present near-win outcomes. Near wins are loss outcomes that resemble wins. Participants completed a relational training task. For one group, near wins were related to the word “loss”. For the other group, near wins were related to the word “almost”. Participants rated how “like a win” near-win outcomes were before and after completing this relational training task. They also made repeated choices between a simulated slot machine that presented near wins and one that did not. Participants who acquired derived relations between near-win outcomes and “loss” showed a reduction in the near-win effect on both preference and verbal ratings. These results suggest that verbal processes may contribute to preferences for slot machines that present near-win outcomes.