The rate of change for the 5-choice serial reaction timed task testing metrics; (A) correct responses, (B) incorrect responses, (C) omissions, (D) accuracy, (E) premature responses, and (F) perseverant responses were assessed over time. All animals completed 100 trials per day of testing. Both photon and proton irradiated groups rates of decline were significantly steeper than sham for correct, incorrect, and premature responses. In addition, photon and proton irradiated groups had an increased rate of omissions overtime compared with the sham group. Mean ± standard error of the mean is shown, n = 15–12/group. *P < .05, **P < .01, and ***P < .001 compared with sham). Abbreviation: RT = radiation therapy.