Neuropsychological testing has become a valuable tool in the management of cerebral concussion. Neuropsychological testing is now routinely utilized by the majority of National Football League (NFL) teams and has been mandated for all athletes within the National Hockey League (NHL). Previous research has demonstrated memory dysfunction in college athletes following concussion. However, more research in this area is needed, especially in younger athletes. PURPOSE: This study evaluates differences in test performance in a sample of concussed High School athletes at 2 days post-injury and at 8 days post injury. The diagnosis of concussion was made by athletic trainers if there was any change in mental status or if the athlete complained of post-concussion symptoms. METHODS: Data from 45 concussed High School athletes are compared to an athlete control group, matched by age (N = 27). The concussed sample consisted of football players (N = 30), soccer athletes (N = 6) and athletes from 4 other sports which included ice hockey basketball and baseball (N = 9). These data were part of a larger data set of over 275 concussed High School, college and Professional athletes. The control group consisted of swimmers (N = 25) and football players (2). The concussed sample was predominantly male (N = 42) while the control group consisted of 18 males and 9 females. All athletes were evaluated using the ImPACT computerized neuropsychological software package. This program yields composite scores derived from tests of reaction time, memory and processing speed. For this study, test performance on the memory composite index was evaluated. RESULTS: An initial Analysis of Variance (ANOVA) did not reveal any differences between the concussed and control (non-concussed) groups on baseline testing (F = 1.54, p < .22). The results of an Analysis of Variance (ANOVA) analysis 2 days post-injury revealed highly significant differences between the concussed and control groups in the areas of memory (F = 12.58, p < .0007). These differences in memory performance between the concussed and control group persisted at day 8 following injury (F = 5.59, p < .02). CONCLUSIONS: Neuropsychological testing has become increasingly utilized in the diagnosis and treatment of concussion. Significant deficits in the area of memory are evident at 8 days after concussion. Neuropsychological testing can provide valuable information on recovery in athletes and should be considered when making return to play decisions.