Diagnosing Mental Illness Using Electroencephalography

Just talking with a professional is often the best way to identify a deficiency in the brain. When something is amiss in the cells of the brain, a person may find it hard to speak coherently, stay on topic or remember the details of words spoken moments before. While this conversation can sometimes help experts to spot a mental health issue, it can be difficult for these same experts to understand why the mental health of the person is at stake. In other words, they may see the symptoms but not see the cause.

An electroencephalogram, or EEG, is one tool mental health professionals can use to dig into the workings of the brain in order to definitively diagnose a disease that could impact behavior. While the test is an exciting scientific development, as it does seem capable of providing valuable information that could be used in the fight against some kinds of disease, it might not be the right way in which to address all types of mental health dysfunction.

How an EEG Works

Many diagnostic tests performed on the brain look for structural difficulties that could cause shifts in behavior. Tumors, bone shards and other structural damage can pop into focus in an x-ray or an MRI scan, and they can help the treatment team to develop a proper plan of action. An EEG works just a little differently. Instead of providing information about what the brain and associated structures look like, an EEG provides a snapshot of how the brain is actually working.

During an EEG, small electrodes are placed on the outside of the head, and they’re attached to a computer. This computer measures all the electrical impulses that brain cells trade with one another, and all the portions of the brain that are at work. As the test moves forward, the provider of the test might ask people to perform certain types of activities, like problem solving or storytelling, and then measure how the electrical activity changes due to those behaviors. Even if people don’t perform tasks, the provider of the test might record what the person is doing at each moment, so interpreters can measure how the brain cells are functioning.

As an article in the Annals of Clinical Psychiatry points out, this test is attractive because it doesn’t rely on patient cooperation. People who are hostile to the idea of taking a test, or who are unable to participate in the test in a reasonable way, can still be assessed with an EEG, as their brain cells will trade electrical impulses whether the person wants to be tested or not.

An EEG might also be attractive to a patient, as there are no painful needles or intrusive medical interventions required. The electrodes are small and easy to ignore, and the test goes by relatively quickly. People afraid of invasive medical tests might find an EEG to be a reasonable alternative.

Traditional Uses

An EEG can be helpful when medical practitioners are trying to determine if a client has epilepsy, according to the Mayo Clinic. This disorder can cause unusual electrical activity in the brain that can lead to seizures.

Any of these issues could be caused by an unusual spark of activity deep inside the brain, and an EEG could bring that issue into sharper focus. When paired with an interview and a full medical workup, the information in an EEG could provide medical experts with a great deal of data that could be used to amend a person’s illness.

Unfortunately, reading an EEG is sometimes difficult. Experts typically compare one person’s results with the results of healthy people, and when discrepancies appear, the experts look for other scans that also seem askew and provide the same diagnosis when two sets of scans seem to synch. It’s all very complicated, and sometimes, small details are missed while the wrong signals are augmented.

As a result, EEGs can provide misleading information, and that might lead to mistaken diagnoses.

In fact, according to a study in The Psychiatrist, false positives provided by EEGs can be as high as 50 percent, and those who have mental illnesses may have even more false positives than the general public. It’s a serious problem, and it should be considered whenever this kind of test is ordered. It simply cannot replace traditional diagnostic methods, and sometimes, the information it provides isn’t exactly reliable.