Organic Mental Disorder Causes and Treatment

An older woman with an organic mental disorder

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An organic mental disorder refers to a decrease in mental functioning that is not the result of a psychiatric condition. Sometimes this term is used interchangeably with organic brain syndrome (OBS) or chronic organic brain syndrome, but is now generally referred to as a neurocognitive disorder.

Here we share some of the potential causes of an organic mental disorder, along with a few of the most common symptoms. We also talk about the various treatment options when this type of condition exists.

At a Glance

An organic mental disorder can be caused by a brain injury, disease, exposure to toxins, and more. Trouble concentrating and bouts of confusion are common symptoms. While complications can sometimes arise, organic mental disorders are generally treated with medication and therapy.

What Causes an Organic Mental Disorder?

Organic mental disorders can have numerous possible causes. Among them are damage or injury to the brain from:

  • Cancer
  • Chemical or hormonal imbalances
  • Degenerative conditions such as Alzheimer's disease, Huntington's, Parkinson's, and Cruetuzfeldt-Jakob disease
  • Exposure to toxins like lead and pesticides
  • Infection
  • Lack of oxygen (anoxic injury)
  • Metabolic syndrome
  • Physical trauma, such as a concussion or other head injury
  • Vitamin deficiencies

Heavy alcohol use can also contribute to the development of an organic mental disorder. In cases such as these, this type of disorder is secondary to alcohol dependence.

Symptoms of an Organic Mental Disorder

Someone with an organic mental disorder may have difficulty concentrating for a long period of time or get confused when performing tasks that are routine. They might also have trouble managing relationships and collaborating or communicating with colleagues, friends, or family.

Other symptoms of an organic mental disorder or neurocognitive disorder include:

  • Agitation
  • Delirium
  • Dementia

The exact symptoms a person may experience can vary depending on the cause of the disorder. If any of these symptoms are present, seeking medical attention is important to finding their cause and deciding the best treatment.

How an Organic Mental Disorder Is Diagnosed

A blood test, spinal tap, or electroencephalogram (EEG) may be administered to diagnose organic brain syndrome or an organic mental disorder. Imaging of the brain, like with a CT scan or MRI, can also be useful, depending on the underlying cause.

While "organic disorders" was removed from the fourth edition of the Diagnostic and Statistical Manual (DSM) as a diagnostic category, many mental health professionals still use this terminology to describe these conditions.

Potential Organic Mental Disorder Complications

Some organic mental disorders are only temporary, but others get worse with time. The chance of recovery or the outlook of a person's condition with this type of disorder depends on a number of factors, most notably the cause of impaired brain function.

Organic mental disorders that don't respond to treatment often result in an inability to function independently or to interact with others. This can lead to the need for assistance with activities of daily living.

Treatments for an Organic Mental Disorder

Although the diagnosis of an organic mental disorder (or neurocognitive disorder, as it is now referred to) can be frightening, there are resources available to help. Plus, research indicates that the effectiveness of organic mental disorder treatments is improving.

Specific treatments that are best for a person with an organic mental disorder vary based on the underlying cause of the disorder. Medication may be prescribed to manage aggressive behaviors. Rehabilitation therapy can also help patients recover function in the parts of the brain affected.

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Verywell Mind uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
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By Ann Logsdon
Ann Logsdon is a school psychologist specializing in helping parents and teachers support students with a range of educational and developmental disabilities.