Friday, March 13, 2009

Doidge (Neuroplasticity) review - part 3 (Schwartz)

Doidge devotes a chapter to discussing obsessive-compulsive disorder. He claims that a treatment developed by Jeffrey M. Schwartz is "plasticity-based". The implication is that other psychological treatments for OCD are NOT "plasticity-based."

Schwartz has published articles in the literature going back into the 1980's looking at OCD patients using PET imaging.

I do not find any good study in the literature about Schwartz's particular technique, as published in his book, in particular no study comparing his technique with CBT.

Also the theory is presented that OCD is caused by a failure for the caudate nucleus in the brain to "shift gears automatically", and that the therapy described is a means of "shifting gears manually." While there are a variety of brain metabolism changes in OCD, I think it is an overly strong statement to believe that this is literally true. One could use the idea of the "caudate gear box" as a metaphor, but it may be quite inaccurate, or at least poorly supported by clear evidence, to be taken literally.

So it concerns me that the chapter in Doidge's book about the "brain lock" approach is more of a book plug than something founded on solid evidence. Doidge could well have made the case that CBT is a type of "neuroplasticity-based treatment". In fact, there is good data to support such a case--including numerous imaging studies--and including a recent paper which Schwartz himself co-authored, which shows various regional changes in brain metabolism associated with improvement in OCD symptoms from intensive CBT:
http://www.ncbi.nlm.nih.gov/pubmed/18180761

Yet, I think it is important to be open about any new therapeutic idea--it may be that the "brain lock" therapy for OCD could be helpful to many people. It's just that Schwartz's book has been given an endorsement by Doidge without a convincing amount of good evidence, while minimizing the robust evidence favouring CBT.

2 comments:

  1. Thanks Garth.

    I had problems with this section for other reasons, and didn't pick up on your point, which is a good one.

    Overall, I'd say Doidge is taking a fairly narrow look at particular characters in the neuroscience field, rather than a broad sweep of the research. There's nothing inherently wrong with that approach as long as people are aware that there may be omissions.

    Martin Walker
    www.mindsparke.com
    PS. My own take: The Brain That Changes Itself - Compulsion, Learning & Unlearning

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  2. Very interesting. I prefer ERP myself!


    www.itsmewithocd.blogspot.com

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