Objective: During the acute and post acute period following a mild traumatic brain injury (mTBI) multiple cognitive processes are negatively affected. Prior studies have reported numerous cognitive domains affected during the acute and post-acute period. Studies have demonstrated cognitive recovery, with subjective and objective assessments, that within days to weeks these cognitive abilities are recovered. This study examines the recovery of neurocognitive functions longitudinally. Method: In this study, we compared 12 adults entering an emergency department that met the criteria for a mTBI to a healthy control group of 13 adults. The neuropsychological evaluation for the mTBI group was performed within 10 days of the injury and 4 months following the injury. Results: The results demonstrate the mTBI group has significant deficits in processing speed, attention and concentration, as well as verbal and visual memory compared to the control group at baseline. The mTBI group showed cognitive recovery in most cognitive areas at the four month follow-up. Processing speed and visual memory were still significantly below the performance of the control group at the 4-month post-assessment. Conclusion(s): The results support prior studies that processing speed and memory may be the most sensitive cognitive domains affected by a mTBI. Furthermore, this study reveals individuals that experience a mTBI may still experience impairment in these cognitive domains 4-months post injury.