Co-registering, chronic, and naturalistic assessments of the electrophysiological and behavioral features of the murine stress response can teach us how stress-behaviors are mechanistically driven by electrophysiological activity in neural circuits, how those relationships change over the course of the multi-week developing response to chronic ongoing stress, and how these changes ultimately contribute to the pathogenesis and progression of major depressive disorder and other psychiatric conditions. However, the long duration and multiplexed nature of the murine stress response have long been barriers to achieving such understandings. To address the need for technology that better captures the time progression of the murine stress response, we engineered the first-ever chronic recording system capable of gathering both behavioral and electrophysiological data in a naturalistic environment for freely-moving mice. Building from previous unpublished work at our lab, we first developed 16 units of a novel photointerrupter-based, Arduino-controlled digital phenotyping system capable of simultaneously recording 50+ behavioral metrics at a sub-second resolution continuously for weeks at a time. Subsequently, with the goal of assisting the concurrent exploration of brain mechanisms and behavior, we engineered a scaffold and cabling structure to support an ultra low-resistance commutator that allows chronic, multi-region brain electrophysiological recordings and integrated it into our digital behavioral phenotyping system. Our novel co-recording system is now fully operational and, along with allowing chronic electrophysiological recordings, supports measures of eating, drinking, food and sugary drink preference (a measure of anhedonia), locomotor activity, sleep, and actigraphy, all the while using 24/7 video tracking to allow detailed classification of behaviors at sub-second resolution. The system is also compatible with standard assessments in the field, including daily weight and fur checks. To demonstrate the duration of its co-recording capabilities, we implanted a cohort of mice with electrodes in three brain regions involved in the murine stress response – olfactory bulb, dorsal hippocampus, and medial prefrontal cortex – and recorded for five weeks. This is the first system to ever produce highly dense behavioral and electrophysiological data simultaneously and continuously over such a period of time.


Details:
DATE: Friday, April 30, 2021
TIME: 10:00 am - 12:00 pm
LOCATION: Zoom https://umich.zoom.us/j/93571968494)
Chair Committee: Brendon Watson, Tim Bruns, Cindy Chestek