2 signiﬁcant diﬀerences were noted between the concussed players’ baseline test scores and the concussed and control players’ test scores during the 24 hour and 5 day assessments. By the 10 day reevaluation, players who had sustained a con- cussion were performing at nearly the same level as their matched controlled peers. This model suggested that there is a typical, and relatively quick, recovery curve that occurred in healthy, young, motivated athletes when they were allowed to rest. This is especially true when there are no complicating psychosocial or medical factors, which are more often seen in clinical populations. The SLAM model was initially instituted as a controlled laboratory to more accurately determine the acute neu- rocognitive cost to any individual suﬀering a single mild concussion, and to plot the typical recovery curve for clinical applications. Today this model is a standard part of the sports medicine concussion assessment and management programs at many high schools, universities, and professional sports teams, to protect athletes from the dangers of returning to play before complete resolution of neurologic and cognitive concussion symptoms. By having a preseason baseline assess- ment, athletic trainers and team physicians can better eval- uate and treat concussions when they occur. This helps to ensure that an injury, no matter how mild, can be properly assessed and treated appropriately in order to reduce the potential severe consequences of a second injury. A rare condition known as second impact syndrome (SIS) [8] can occur, especially in adolescents who have sustained two minor impacts in close proximity. It is hypothesized that these closely occurring injuries can result in a catastrophic increase in intracranial pressure due to dysfunction of auto- regulation of the cerebrovascular system. Identifying concus- sions in order to allow full neurologic recovery is critical to avoid further injury and to facilitate prudent return-to-play (RTP) decisions. 2. Return to Play Based on this line of research which has been expanded and reﬁned by many other neuroscientists, speciﬁc recommenda- tions have been created to guide safe return-to-play (RTP) decisions. In 2008, the Third International Conference on Concussion in Sport was held in Zurich which produced a consensus on managing sports concussions [9]. Based on these guidelines, a gradual RTP protocol was created. The protocol goes into eﬀect once an athlete is symptom free while at rest. As the athlete completes each component and remains symptom free, he or she moves to the next step. First, light aerobic exercise, which keeps the heart rate at less than 70% of the maximum, predicted heart rate is recommended. If symptoms do not return, the second stage involves en- gaging in sport-speciﬁc exercises that do not involve any potential impact to the head. For example, these would be skating in ice hockey or running in soccer. Third, noncontact training drills are added, such as passing drills in ice hockey or football, along with beginning progressive resistance training. Fourth, the athlete can engage in a full contact practice and return to normal training activities. Once they have reached this stage without experiencing a return of symptoms, they are able to return to full play. Rehabilitation Research and Practice 3. Application of SLAM to Military Concussions Another area where concussions have gained signiﬁcant attention is in the current conﬂicts in Iraq and Afghanistan. One of the signature injuries of Operation Iraqi Freedom (OIF), Operation Enduring Freedom (OEF), and now Oper- ation New Dawn (OND) has been traumatic brain injury. Approximately 79% of combat-related TBIs are caused by improvised explosive devices, leading to blast concussive in- juries [10]. Traumatic brain injuries that occur as a result of a blast can involve any aspect of the four blast phases [11]. The primary phase is characterized by atmospheric over- pressurization immediately followed by a vacuum or atmo- spheric underpressurization as a function of the initial blast wave. Typical injuries resulting from this blast phase are damage to hollow organs such as rupture of the tympanic membranes, pulmonary barotrauma, and acute gas emboli (AGE) in the cerebrovasculature and cerebrospinal ﬂuid [12, 13]. The secondary phase involves objects that are placed in motion due to the blast leading to blunt and penetrating injuries [12, 13]. For example, a secondary phase of injury can occur when blast debris (rocks, cement, etc.) hits a ser- vice member. The tertiary blast phase occurs when service members are thrown oﬀ of their feet and hit stationary objects, which often results in acceleration-deceleration and blunt head trauma injuries. Quaternary-phase injuries are sustained following a blast and may include burns, toxic inhalation, exposure to radiation, asphyxiation, dust inhala- tion, and crush trauma [12, 13]. The primary and quaternary phases of combat blast injury make it considerably more complex than the typical sports related concussion, which involves blunt trauma and acceleration-deceleration dynam- ics (similar to secondary and tertiary phases in combat blast). 4. Using SLAM in the Military: Return to Duty The SLAM baseline methodology was recently engaged by the military to better assess and manage concussions. Con- cussions are identiﬁed in the ﬁeld by a combination of description of blast exposure (being within 50 meters of a blast), symptom report, and use of a brief mental status/ neurocognitive assessment measure, the Military Acute Con- cussion Evaluation (MACE) [14], which is based upon the standardized Assessment of Concussion (SAC) from the sports literature [15]. In May 2008, the military began using the Automated Neuropsychological Assessment Metric (ANAM) to assess neurocognitive functioning in all pre- deployers. This provided baseline neurocognitive data for military members to compare to postconcussive test results to determine the extent of injury. Using the sports concussion literature, the military has created guidelines for returning military members to duty following a concussion. In 2010, a statement was issued that required designated periods of rest following a concussion (Deputy Secretary of Defense). Procedures were established that specify when a concussion evaluation is mandatory. Clinical practice guidelines are available to medical person- nel in the deployed environment regarding the evaluation and treatment of concussions. These mandatory events are