Objective: Memory is affected following traumatic brain injury. Prior studies of memory processes in concussed athletes have found a decrease even in mildly injured athletes. ImPACT is a computerized neuropsychological test battery used to evaluate cognitive functioning in concussed athletes. The working memory (WMI), immediate memory (IMI), and delayed memory indices (DMI) are ImPACT supplemental composite scores developed to provide additional markers of injury and recovery. The purpose of the current study is to determine if scores on these indices are sensitive to concussion. Method: Participants included 75 athletes, all of whom had received baseline and post-injury testing on ImPACT. The sample included predominantly male athletes (74.7%). Average age was 16.58 with an average of 10 years education. Results: Baseline ImPACT scores on the WMI were compared to post-injury scores on the same index using a dependent measures t-test. Results indicated a statistically significant decline in WMI following injury, t(74) = 3.02, p = < 0.001, and the DMI, t(73) = 5.81, p < 0.001. Conclusions: This study suggests that the WMI, IMI, and DMI ImPACT scores are useful in determining cognitive difficulties in concussed athletes. It appears that all three of these indices were significantly lower in concussed athletes when compared to these athletes’own pre-injury test scores.