Antidepressant or Therapy? EEG Offers Insight
Using an electroencephalogram (EEG) to measure a patient’s emotional boost upon receiving a reward can reveal whether a selective serotonin reuptake inhibitor (SSRI) or cognitive behavioral therapy (CBT) would be more beneficial, according to a study in the Journal of Clinical Psychiatry.
“There are serious considerations that go into prescribing either of these treatments,” said study lead author Katie Burkhouse, PhD, assistant professor of psychiatry at the University of Illinois at Chicago. “SSRIs can have unwanted side effects, while CBT requires a significant amount of time and commitment, and practitioners trained in delivering CBT can be hard to find and those that practice this form of therapy may be booked and not able to take on new patients.”
The study focused on reward positivity—electrical activity generated in the brain in response to reward—as a potential measure of improvement in patients with depression and anxiety. Previous research showed reward positivity is consistently lower in such patients.
At baseline, 63 patients with depression or anxiety received an EEG while completing a computer task. During the activity, 2 doors appeared on a screen, and participants were told if they chose the correct door they would receive a monetary award, and if they chose the incorrect door, they would lose money.
Participants were then randomized to treatment with an SSRI or CBT for 12 weeks. After the treatment period, participants again completed the computer task during another EEG session.
“The more that reward positivity increased from the baseline measurement to the final post-treatment measurement, the more participants reported a lessening of their depression or anxiety symptoms with treatment,” said Dr. Burkhouse. “This means that reward positivity closely follows symptom improvement as treatment progresses, and as such, can be used to help determine if a particular treatment is working for a patient or not.”
The study also revealed that patients with blunted reward positivity at baseline had bigger drops in depressive symptoms with an SSRI as opposed to CBT.
“We haven’t had an objective way to measure whether a patient is improving with treatment or which patients will do better on SSRIs vs cognitive behavioral therapy,” said Dr. Burkhouse, “until now.”
Burkhouse KL, Gorka SM, Klumpp H, et al. Neural responsiveness to reward as an index of depressive symptom change following cognitive-behavioral therapy and SSRI treatment. Journal of Clinical Psychiatry. 2018;79(4).