Brain injury is complex, though not always visible and sometimes seemingly minor.

It can cause physical, cognitive, social, and vocational changes affecting an individual for a short period of time or permanently. Depending on the extent and location of the injury, symptoms caused by a brain injury vary widely. Some common results are seizures, loss of balance or coordination, difficulty with speech, limited concentration, memory loss, and loss of organizational and reasoning skills.

A traditional 'intelligence test' is not an accurate assessment of cognitive recovery after a brain injury and bears little relationship to the mental processes required for everyday functioning. For example, students with brain injuries might perform well on brief, structured, artificial tasks but have such significant deficits in learning, memory, and executive functions that they are unable to, otherwise, cope.

Recovery from a brain injury can be inconsistent. A student might take one step forward, two back, do nothing for a while, and then unexpectedly make a series of gains. A plateau is not evidence that functional improvement has ended.