Impairments in expression of devaluation in a Pavlovian goal-tracking task, but not a free operant devaluation task, after fentanyl exposure in female rats.

In laboratory animals, there are numerous demonstrations that past exposure to drugs of abuse can lead to devaluation impairments weeks after the final drug exposure, with the majority of these demonstrations examining effects of exposure to psychostimulants. There has been minimal investigation into whether prior exposure to opiates can lead to devaluation impairments. Here, we first trained female rats that two separate cuelights predicted two different foods and measured Pavlovian goal-tracking responses (Experiment 1) or trained female rats to press two levers to earn two different foods and measured this operant response (Experiment 2).

[Learning about the caregiving relationship in the internship].

Nursing students are confronted with the mysteries of the patient encounter during their internship in psychiatry. From this discovery, questions and enigmas remain to be solved. This ephemeral primary relationship, in a time span of a few weeks, is a source of frustration for them.