Re:Eye Movements vs. Fixed Eye Conditions

Shawn:

Thanks for pointing out the contradiction that is a typo in my 10/23 post.

What I meant to be saying is that involuntary eye fixation rather than voluntary eye fixation on part of the client is likely suggestive of dissociation.

This may be a superfluous statement, but I do not think that involuntary eye fixation causes dissociation, but rather involuntary dissociation likely causes eye fixation.

I also agree with you that this poses a challenge scientifically as to what is an appropriate control condition for eye movements, but certainly is not unscientific - quite to the contrary. IMO it is unscientific to use inappropriate control groups, that based on recent neuroscience findings have a high probability of not showing differential effects. That is, this is a pursuit of probable null findings.

Eyes closed may be a better control condition, though this sometimes still shows spontaneous eye movements. Though you'd expect that to occur in CBT as well and you occassionally can witness it in individuals who do not undergo any therapy at all, nor hae they been exposed to any. However, in my clinical expereince, closing eyes can certainly increase vividness of imagery when recalling traumatic material, thus there may be another difficult to quantify effect.

IMO, there are a few different ways to look at the effects of eye movements and or bilateral/dual attention stimulation that would aid to our understanding. One would be to actually monitor eye movemnts with an apparatus similar to that used schizophrenia research and obtain correlational data, preferably including other physiological indices including heart rate, blood pressure and skin conductance - obviously this would be a correlational study.

A scipt driven imagery study using PET or fMRI with and without bilateral/dual attention stimulation - it would be interesting to including a fixed eye condition. My prediction would be increased brain activity in the brain areas that commonly show hypofunction in PTSD when dual attention/bilateral stimulation is added.

Finally, I'd still like to see a dismantling study with a clinical population that uses the EMDR protocol with and without bilateral stimulation, with adequate power to address the question. I think that no instructions as compared to eye fixation instructions make for a superior control group. And is some of the subjects engage in eye movements voluntarily, so be it. Ideally, this treatment would be administered through a standardized computer program and dual attention/bilateral stimulation be applied with a mechanical device. IMO such a set-up would certainly decrease the effectiveness of treatment, it would ceratinly make any dismantling research easier to interpret.

Replies:

Re:Eye Movements vs. Fixed Eye Conditions, by Cahill, 10/28/02 Re:Eye Movements vs. Fixed Eye Conditions, by Ulrich Lanius, Ph.D., 11/01/02

| Behavior OnLine Home Page | Disclaimer |

Copyright © 1996-2004 Behavior OnLine, Inc. All rights reserved.