RT Journal Article
SR Electronic
T1 Anhedonia following mild traumatic brain injury in rats: A behavioral economic analysis of positive and negative reinforcement
JF bioRxiv
FD Cold Spring Harbor Laboratory
SP 527895
DO 10.1101/527895
A1 Pelin Avcu
A1 Ashley M. Fortress
A1 Jennifer E. Fragale
A1 Kevin M. Spiegler
A1 Kevin C.H. Pang
YR 2019
UL http://biorxiv.org/content/early/2019/01/23/527895.abstract
AB Psychiatric disorders affect nearly 50% of individuals who have experienced a traumatic brain injury (TBI). Anhedonia is a major symptom of numerous psychiatric disorders and is a diagnostic criterion for depression. Recently, anhedonia has been divided into consummatory, motivational and decisional components, all of which may be affected differently in disease. Although anhedonia is typically assessed using positive reinforcement, the importance of stress in psychopathology suggests the study of negative reinforcement (removal or avoidance of aversive events) may be equally important. The present study investigated positive and negative reinforcement following a rat model of mild TBI (mTBI) using lateral fluid percussion. Hedonic value of and motivation for reinforcement was determined by behavioral economic analyses. Following mTBI, the hedonic value of avoiding foot shock was reduced. In contrast, the hedonic value of escaping foot shock or obtaining a sucrose pellet was not altered by mTBI. Moreover, neither motivation to avoid or escape foot shock nor motivation to acquire sucrose was modified by mTBI. Our results suggest that individuals experiencing mTBI may experience more stress because of poor proactive control of stress resulting from reduced hedonic value of avoiding aversive events.