A person does not need to be "knocked out" or in a coma to have sustained a traumatic brain injury. There does not even need to be a direct blow to the head in order to sustain a brain injury. Often the neurological examination done at the Emergency Room and otherwise will be normal. A routine neurological examination is not designed to pick up the type of subtle cognitive impairments that can result from a diffuse axonal injury.

Often neuroradiological diagnostic tests may be perfectly normal as these tests are also often unable to pick up the type of microscopic damage that results from an acceleration/deceleration injury to the brain. There are certain classic symptoms such as headaches, dizziness, blurred vision, tinnitus, fatigue, impaired consciousness, confusion, personality changes, impulsivity, etc. associated with post concussion syndrome and even though the plaintiff suffers a "mild traumatic brain injury" the resulting cognitive and emotional impairments can have a devastating effect on the person's ability to function and work.

This is because each individual is unique and the number and location of brain cells injured may be unique for each individual, although there are certain typical symptoms associated with post-concussion syndrome, each individuals symptoms and impairments will be somewhat individualized and effect the individual in different ways.

In an traumatic brain injury caused by an auto accident, there need not be a big collision. Automobile crashes at 10 mph can exert a force ten times the force of gravity on the skull and are competent to cause diffuse axonal injury. The person himself may not realize that he has sustained a traumatic brain injury or make the association between his symptoms and dysfunction and the accident until weeks or months later.

The traumatic brain injury may not be accompanied with any visible injuries or evidence of trauma to the head or body and the person may be able to continue to function adequately particularly on trained or familiar tasks. It is not until the person is challenged that his or her deficits become recognized that there are often associated hearing or vision difficulties. This occurs despite the fact that there is no injury to the eyes or ears since the injury is to the brain and that part of the brain which controls these functions.

They are often associated vestibular injuries, which result from the same forces that caused the brain injury. Emotional sequelae is often associated with traumatic brain injury and just because the person becomes depressed does not suggest that the etiology of the problems are psychological rather than neurological. An injured individual often may be a poor historian as to the amount of time or whether in fact there was a loss of consciousness. Many of the treating neurologists or interns that see the person may not diagnose a traumatic brain injury or post- concussion syndrome because they are unfamiliar with and untrained in minor as opposed to more severe forms of brain injury.

The amount of anatomical injury to the brain, which is all that "mild", "moderate" or "severe"   refers to, does not correspond exactly with the functional consequences of the injury; and that there are often personality and behavioral changes associated with post-concussion syndrome."