OBJECTIVE: The purpose of the present study was to examine if concussion symptoms worsened immediately (i.e. 20 minutes) following performance on a computerized neurocognitive test. RESEARCH DESIGN: Cross-sectional study; Level of evidence, 2. METHODS AND PROCEDURES: A total of 165 athletes with a concussion participated in the study. Participants completed the Immediate Post-concussion Assessment and Cognitive Test (ImPACT) and Post-concussion Symptom Scale (PCSS) at baseline, 3 and 10 days post-concussion. Participants completed a second PCSS following the ImPACT test at 3 and 10 days post-injury. MAIN OUTCOMES AND RESULTS: Athletes with a concussion exhibited greater symptoms post-neurocognitive test 3 days post-concussion on headache (p = 0.01), nausea (p = 0.03), dizziness (p = 0.03), sadness (p = 0.005), mentally foggy (p= 0.002) and visual problems (p = 0.007). Athletes with a concussion demonstrated increased symptoms on sadness (p = 0.00) and difficulty remembering (p = 0.03) at 10 days post-injury. Athletes also demonstrated neurocognitive impairments in verbal memory (p = 0.009) and slower reaction time (p = 0.01) 10 days post-concussion and visual memory (p = 0.000) and motor processing speed (p = 0.000) impairments at 3 days post-injury. CONCLUSION: The current study suggests that there may be an increase in concussion symptoms following a 20-minute cognitive task. Thus, it illustrates the need for clinicians to make sure they are symptom free with both physical and cognitive testing.