Induction when rats lick for 1% liquid-sucrose reinforcement

Previous research reported that rats responding for 1% liquid-sucrose reinforcement when 32% sucrose reinforcement is upcoming will decrease their response rate (contrast) if licking is the dependent measure and increase their response rate (induction) if pressing a lever is the dependent measure. The present study investigated whether induction could be observed when licking served as the dependent measure and whether induction in lever pressing and contrast in licking behaviour could be concurrently observed. Experiment 1 found induction when rats licked to earn the rewards but consumed them at a location separate from the spout licked to earn them. Experiment 2 also found induction when rats earned (and consumed) rewards by licking the same spout throughout the session. Experiment 3 separately measured instrumental lever pressing for sucrose rewards and licking the sucrose during the reward period. We found that both measures increased for 1% sucrose when 32% sucrose reinforcement was upcoming. The present results indicate that the type of response is not the sole determinant of whether contrast or induction is observed. Rather, they suggest that other procedural details, such as the location of reinforcer delivery, influence which effect is observed. The results also indicate that associative processes underlie the appearance of induction in responding for 1% sucrose.     

Emotion-based learning and central executive resources: an investigation of intuition and the Iowa Gambling Task

The role of emotion in complex decision-making can be assessed on the Iowa Gambling Task (IGT), a widely used neuropsychological measure that may tap a different aspect of executive function than that assessed by conventional measures. Most notably, the 'feeling' about which decks are good or bad, often described in relation to IGT performance, seems reminiscent of decision-making based on intuition-linked to a long history of research in decision-making contrasting the 'intuition' versus 'reasoning' styles of problem solving. To test the claim that the performance on the IGT relies more on emotion-based learning than conventional executive resources for normal performance, a group of participants completed the IGT simultaneously with one of two secondary-tasks, one of which (random number generation) is known to load executive resources. A third group performed the IGT with no secondary-task. If performance on the IGT requires the properties associated with intuitive operations, then participants should either show no disruption when completing a secondary-task, or at least show no selective disruption on a secondary-task that loads for executive function. The rate of learning in the three groups was not significantly different. This suggests that the sorts of cognitive resources loaded by traditional executive tasks such as random number generation do not overlap, in the cognitive architecture, with the emotion-based learning skills that are required for Iowa Gambling Task performance. The findings of the present study are also consistent with a previous claim of the Iowa group that emotion-based learning and working memory resources are doubly dissociable.     

Working Through the Trauma of Sexual Assault in an Undergraduate Class

Processing the trauma of sexual assault is a complicated and often prolonged process that may occur both within and outside a formal psychotherapeutic context. The second author describes an undergraduate class that explores various aspects of sexual assault, followed by a paper written by a female student in which she describes how the class impacted her intellectual understanding of and emotional reactions to her own sexual victimization as a high school student. Finally, the authors discuss the concept of “working through” as it applies to recovery from sexual assault, and they propose that a didactic course experience, even if not designed as a therapeutic enterprise, may nonetheless serve such a function.