For victims of a traumatic brain injury (TBI) and their families, side effects such as bipolar disorder and memory loss are tragic, but well known and well understood. But in the last decades, scientists have begun to study another serious side effect of brain damage that may go undetected: schizophrenia.

What is Schizophrenia?

Schizophrenia (Greek for "shattered mind") is a psychotic disorder that affects behavior, mood and thinking. Originally called the schizophrenias due to the association of several varying characteristics and personalities common with the illness. The most widely known symptom, auditory hallucination ("hearing voices"), may not even be present in all who have a diagnosis of schizophrenia. Psychologists break symptoms of schizophrenia into three categories:

. Positive symptoms are behaviors that are not present in normal individuals. Other symptoms include hearing things, delusional though as well as sporadic thought.

. Negative symptoms are symptoms showing loss of normal abilities. They include loss of ability to show or feel emotion, lack of motivation and trouble with speaking.

. Neurocognitive defects are problems with brain function in areas such as memory, problem-solving, attention and social functioning.

Schizophrenia Related to Brain Injury in Patients

Scientists have established that psychiatric conditions such as bipolar and anxiety disorders are more common in patients who have suffered from traumatic brain injuries. Schizophrenia itself has been associated with individuals who have previously suffered brain damage regardless of family history. But it is only since the early 1990s that researchers have begun to explore in depth that connection between brain damage caused by traumatic brain injury and schizophrenia.

Schizophrenia and Brain Injury: Recent Studies

. Among the findings of those studies:

. TBI-associated schizophrenia is true schizophrenia, not another disorder with similar symptoms, according to a 2001 study by Columbia University. Schizophrenia and TBI are now being associated as hand-in-hand illnesses, one usually occurs in the victim of the other.

. Another study in the same year at the University of New South Wales in Australia discovered that TBI patients with schizophrenia-like psychosis had more widespread brain damage and cognitive impairment than TBI patients without psychosis. It also suggested that a family history of schizophrenia and the severity of the brain damage sustained during TBI increased the risk of schizophrenia.

. In 2002, researchers in the state hospital of Hawaii discovered that it can actually take anywhere from 2 to 5 years for psychosis to develop in victims of TBI. Psychosis may be the result of trauma and blunt force to temporal and frontal lobes, for which researchers are attempting to determine.

While the complex nature of schizophrenia makes its cause unclear, as the last study suggests, there is evidence to believe that brain injury directly causes schizophrenia, by damaging the areas of the brain that control higher functions. There is also evidence that a traumatic brain injury may cause psychosis indirectly. Scientists believe that schizophrenia is caused by a combination of genetic susceptibility to the disease and an emotionally or physically traumatic experience that triggers this susceptibility. Some studies exploring the two conditions suggest that traumatic brain injury and its complications may act as such a trigger.

Many physicians know a traumatic brain injury may cause neurocognitive disorders such as trouble with speech, and psychiatric problems like bipolar disorder, but not all are aware of the growing evidence linking schizophrenia with brain damage. It is imperative that after a TBI accident, that a victim consult a psychiatrist to ensure that they return to normal behavior. In addition, brain injury patients and their families should consult an experienced brain injury attorney as they seek to recover costs for expenses such as lost wages, current medical costs and future medical care.