Monday, March 10, 2014

What's wrong with believing in the chemical imbalance theory of depression?

Recruits from an undergraduate psychology course with a past or current episode of depression were led to believe that the purpose of a study (Kemp et al 2014) was to improve understanding of how people respond to learning the cause of their depression. They were administered the Rapid Depression Test (RDT), which they were deceived into believing is a "test of neurotransmitter levels whose results would allow participants to determine whether or not their depressive episode(s) were caused by a chemical imbalance in the brain".

The test
entailed swabbing the inside of the participants' cheeks with a sterile cotton swab and placing the cotton swab into a sterile collection container. Participants were told their saliva sample would be tested in the lab. The experimenter returned 10 minutes later with the results.

In the chemical imbalance
condition, participants were informed that test results indicated that their past/current depression was caused by an imbalance in the neurotransmitter serotonin. Participants were presented with a bar graph of their test results depicting very low serotonin levels relative to levels of other neurotransmitters, all of which were in the normal range. Participants in the control condition, on the other hand, were told their past/current depression was not the result of a chemical imbalance, based on purported test results (and a corresponding bar graph) indicating that all neurotransmitter levels were in the normal range.

The chemical imbalance test feedback made participants significantly more likely to attribute their depression to chemical imbalance, demonstrating that the intervention was effective. Self-stigma was unaffected but chemical imbalance feedback made participants significantly more pessimistic about prognosis. There was some evidence of lowered perceived ability to regulate negative mood states. Participants
in the chemical imbalance condition rated pharmacotherapy as more likely to be effective than psychotherapy. By contrast, expectancies for pharmacotherapy and psychotherapy did not differ significantly in the control condition.

The authors conclude that doctors may be causing harm by encouraging belief in chemical imbalance. The theory may be used as a means of getting patients to take their medication (eg. see my eletter). It can be a surprise to patients when they discover the theory has never been proven. They might be even more upset when they realise they might have done better not to believe it.

(With thanks to blog by Kermit Cole on Mad in America)


Neal said...

I totally agree with this post. I am a beginning psychiatrist working in the United States. I find myself telling people all the time that their illness isn't because they have a chemical imbalance, and they are almost universally grateful for that information. It helps them feel empowered and hopeful about recovery. I never tell people that they "need" medications. Rather, I tell them that medications can sometimes be ONE ELEMENT of a healing/recovery plan that also includes self-care and wellness plus utilization of social and spiritual supports. When someone comes back to me and tells me that they are doing so much better because of the medication, I tell them I'm glad the meds are working, but I also try to emphasize the other choices they have made that also may be contributing to their recovery.
Thank you for this blog - I'm definitely going to become a regular reader.

ellen said...

My story shows that Neal is correct. As a younger person in the '70's and on, I thot (and was told) that I had a "chemical imbalance). For years I tried various antipressants which had terrible effects. One day I came across Elliot Valenstein's book, Blaming the Brain, which definitively establishes that there is no such thing as an "illness" called "depression". He points out the fallacy of the chemical imbalance theory. So - since there was no such things as a depressive illness, I stopped seeking treatment thru medical avenues, I sought out other remedies (in my case Kundalini Yoga), and other lifestyle changes. So happy that someone in the profession like Neal is aware of this.

Oliver said...

How is a study like this even approved? Deliberate deception is a big no-no except under extreme circumstances, and full debriefing is (almost) always required.