Anhedonia following mild traumatic brain injury in rats: A behavioral economic analysis of positive and negative reinforcement.

Anhedonia following mild traumatic brain injury in rats: A behavioral economic analysis of positive and negative reinforcement. Behav Brain Res. 2019 Apr 15;:111913 Authors: Avcu P, Fortress AM, Fragale JE, Spiegler KM, Pang KCH Abstract 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. It has recently been appreciated that reinforcement may be separated into consummatory (hedonic), 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 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, motivation to avoid or escape foot shock or to acquire sucrose was not altered by mTBI. Our results suggest that individuals experiencing mTBI find avoidance o...
Source: Behavioural Brain Research - Category: Neurology Authors: Tags: Behav Brain Res Source Type: research