Alcohol Use Disorder is a chronic relapse disorder driven by the persistence of cravings, despite its deleterious social and health ramifications. The development of adequate treatment requires a comprehensive understanding of the neural circuitry mechanisms underlying the establishment and persistence of alcohol preference. The fruit fly, Drosophila melanogaster, is an ideal animal model to investigate circuits required for alcohol reward memories because of the genetic strategies available that allow for precise manipulation of neurons. Alcohol reward memories in flies requires dopamine and the mushroom body, an associative central brain structure important for olfactory memory and learning. A subset of dopamine neurons, PAM, project to the mushroom body and are critical for the acquisition and retrieval of alcohol reward memories. To determine whether PAM neurons are sufficient for the formation of reward memories, the red light sensitive channelrhodopsin, Chrimson, was expressed to activate target dopaminergic PAM neurons. The optogenetic activation of dopaminergic neurons did not induce a significant odor preference, suggesting that the activation of dopaminergic neurons is not sufficient for odor preference memory. To investigate if circuits responsible for arousal due to ethanol exposure is related to dopaminergic reward circuits, levels of hyperactivity were monitored with Chrimson activation. Because alcohol induced hyperactivity profiles were similar across experimental and genetic controls, the circuits responsible for reward and hyperactivity appear to be distinct.
Huynh, Samantha, and Scaplen, Kristen,
"Mapping neural circuits that underlie alcohol reward memory"
(2016).
Summer Research Symposium.
Brown Digital Repository. Brown University Library.
https://doi.org/10.26300/grky-6105
Each year, Brown University showcases the research of its undergraduates at the Summer Research Symposium. More than half of the student-researchers are UTRA recipients, while others receive funding from a variety of Brown-administered and national programs and fellowships and go …
