World-wide, millions experience mild traumatic brain injury (mTBI) annually, which may lead to persistent neurobehavioral symptoms (NBS). Studies on non-linguistic processing post-mTBI have had mixed results, but few have considered NBS.The relationship between NBS, mTBI and non-linguistic performance was investigated using a novel ERP target detection task. P300 latency and amplitude, response time (RTs) and accuracy were measured from community-dwelling adults with (+mTBI n=18; Female 12) and without mTBI (-mTBI n=21; Female 11). The Neurobehavioral Symptom Inventory (NSI) measured self-reported NBS. We expected +mTBI to show increased P300 latencies and RTs and reduced P300 amplitudes compared to -mTBI. NBS scores predicted target RTs, R2 = 0.125, F (1, 37) = 5.296, p = 0.027, β = 0.354, with no observed difference between +mTBI and -mTBI on RTs, P300 amplitude or latency. Our findings suggest that researchers and clinicians should consider NBS when assessing cognitive function.