Minocycline Ineffective in Treatment of Impulsivity and Attention Impairment Resulting from Traumatic Brain Injury

Virginia M. Milleson*, Kristen M. Pechacek and Cole Vonder Haar, Department of Psychology, West Virginia University, Morgantown, WV, 26505

Field (Broad Category): Neuroscience (Behavioral & Social Sciences) 

Student’s Major: Neuroscience and Psychology 

TBI (traumatic brain injury) has been associated with several cognitive deficits including impulsivity and inattention. Chronic neuroinflammation is linked with both TBI and psychiatric conditions with similar symptoms. Thus, treatments targeting neuroinflammation may relieve such symptoms. Minocycline is a broad spectrum antibiotic that has anti-inflammatory properties. The purpose of this study is to attempt to treat TBI-induced neuroinflammation, and by extension treat impulsivity and inattention. Rats were trained on the five-choice serial reaction time task, an operant task that measures motor impulsivity and attention. In this task, rats first initiate a trial, then there is a five second inter-trial interval in which responding must be inhibited (motor impulsivity). A stimulus light will then be illuminated above one of five nose- poke holes and correctly respond to that hole results in reinforcement (attention). A controlled cortical impact was used to induce a severe bilateral TBI or sham injury. Minocycline or saline was administered via intraperitoneal injection at 45 mg/kg every twelve hours for five days, either one hour or eight weeks after injury. Brain injury increased both impulsivity and inattention. Minocycline beginning at one hour and eight weeks postinjury failed to treat these deficits. Minocycline does not appear to be an effective treatment for TBI-related impulsivity and inattention under these conditions. Future work should consider further characterizing the anti-inflammatory properties of minocycline to fully understand this relationship. 

Funding: 

Program/mechanism supporting research/creative efforts: My efforts were mainly voluntary.