Lea Hsu
Research Mentor(s): Shelly Flagel
Mentor Department: Psychiatry/MBNI
Authors: Lea Hsu, Stephanie Desrochers, Shelly Flagel
Session: Session 6 (3:00pm – 3:50pm)
Presentation Type: Poster 27
Abstract
Many of our daily behaviors are guided by environmental cues. For instance, the sight of a sign advertising tasty food at the grocery store may motivate us to browse and make purchases. While these associations often promote adaptive behavior, they can also lead to maladaptive or dangerous responses, such as cue-induced drug seeking in individuals with substance use disorders. To study the behavioral and neural bases of these stimulus-response associations in a laboratory setting, we employ a Pavlovian Conditioned Approach (PavCa) Paradigm in rats. This paradigm involves the presentation of a lever-cue stimulus, followed by an immediate food reward. Rats that interact primarily with the lever are categorized as sign-trackers, and are thought to assign greater incentive value to the cue itself. On the other hand, those that interact more with the food port are identified as goal-trackers, representing a more goal-, rather than cue-, directed, behavioral pattern. These phenotypes reveal how individuals differ in their responses to the same cue, highlighting variations in motivation for reward-outcomes and reward-predictive cues. In the present study, we examined the bidirectional neural activity that occurs after cue exposure in these different phenotypes. We focused on the paraventricular nucleus of the thalamus (PVT), which has previously been implicated in the control of sign-tracking behavior. Following PavCA behavioral testing, markers such as CFos and phosopyruvate dehydrogenase were used in immunohistochemistry procedures to label neural activation and inhibition, respectively. Imaging and cell counting suggest that there are different patterns of inhibition and excitation in the PVT between the sign-tracker and goal-tracker phenotypes, further indicating that this brain region plays a critical role in mediating individual differences in cue-motivated behaviors. Understanding the significance of environmental cues and the neural mechanisms by which they motivate particular behaviors allows us to apply these concepts to have a deeper understanding of reward-based and other related disorders in humans.
