Objective: Neuropsychological performance in patients with epilepsy is multi-factorial, and in addition to the underlying brain substrate giving rise to the epilepsy, additional factors affecting neuropsychology may include anti-epilepsy drugs, ictal and post-ictal effects, as well as the disruptive effects of inter-ictal discharges. The preoperative evaluation for epilepsy surgery includes neuropsychological evolution to establish functional correlates of the seizure onset region, which in turn, can be used to forecast risk of post-operative cognitive decline. We describe a patient undergoing evaluation for epilepsy surgery whose neuropsychological profile was significantly affected by EEG discharges/subclinical seizures that, had simultaneous EEG recording not been obtained, the magnitude of cognitive impairment would have been overstated. At Emory University, we now obtain simultaneous EEGs on the majority of epilepsy surgery candidates undergoing neuropsychological evaluation. Not only should the potential for abnormal discharges affecting neuropsychological factor into clinical case formulation and decision making on the individual patient level, but this also raises potential concerns that estimates of post-operative neuropsychological decline may be underestimated based upon failure to properly characterize discharge effects during neuropsychological evaluation in previous epilepsy surgery series.