TY - JOUR
T1 - On EMDR
T2 - Measuring the working memory taxation of various types of eye (non-)movement conditions
AU - van Veen, Suzanne C.
AU - Kang, Sahaj
AU - van Schie, Kevin
N1 - Funding Information:
There is no conflict of interest in the present study for any of the authors. This research was funded by a TOP-grant ( 40-00812-98-12030 ) from the Netherlands Organization for Health Research and Development (ZonMw) awarded to Marcel van den Hout and Iris Engelhard from which the salaries of SCvV and KvS were paid.
Publisher Copyright:
© 2019 The Authors
PY - 2019/12
Y1 - 2019/12
N2 - Background and objective: A recent, large randomized controlled trial employing different forms of eye (non-)movements in eye movement desensitization and reprocessing (EMDR) showed that fixating the eyes either on a therapist's moving or non-moving hand led to equal reductions in symptoms of post-traumatic stress disorder (PTSD). However, numerous EMDR lab analogue studies found that eye movements produce larger memory effects than eyes stationary. These beneficial effects are typically explained by differences in working memory (WM) taxation. We tested the degree of WM taxation of several eye (non-)movement conditions used in the clinical trial. Methods: All participants (N = 40) performed: (1) eyes moving by following the experimenter's moving finger, (2) eyes fixed on the experimenter's stationary finger, (3) eyes closed, or (4) looking unfocused into the room. Simultaneously they performed a simple reaction time task. Reaction times are an objective index of the extent to which different dual attention tasks tax WM. Results: Eyes moving is more taxing than eyes fixed, while eyes fixed did not differ from eyes unfocused. All conditions were more taxing than eyes closed. Limitations: We studied WM taxation in a laboratory setting; no clinical interventions were applied. Conclusions: In line with previous lab studies, making eye movements was more taxing than eyes fixed. We discuss why this effect was not observed for reductions in PTSD symptoms in the clinical trial (e.g., differences in dependent variables, sample population, and intervention duration). For more comprehensive future insights, we recommend integration of mechanistically focused lab analogue studies and patient-oriented clinical studies.
AB - Background and objective: A recent, large randomized controlled trial employing different forms of eye (non-)movements in eye movement desensitization and reprocessing (EMDR) showed that fixating the eyes either on a therapist's moving or non-moving hand led to equal reductions in symptoms of post-traumatic stress disorder (PTSD). However, numerous EMDR lab analogue studies found that eye movements produce larger memory effects than eyes stationary. These beneficial effects are typically explained by differences in working memory (WM) taxation. We tested the degree of WM taxation of several eye (non-)movement conditions used in the clinical trial. Methods: All participants (N = 40) performed: (1) eyes moving by following the experimenter's moving finger, (2) eyes fixed on the experimenter's stationary finger, (3) eyes closed, or (4) looking unfocused into the room. Simultaneously they performed a simple reaction time task. Reaction times are an objective index of the extent to which different dual attention tasks tax WM. Results: Eyes moving is more taxing than eyes fixed, while eyes fixed did not differ from eyes unfocused. All conditions were more taxing than eyes closed. Limitations: We studied WM taxation in a laboratory setting; no clinical interventions were applied. Conclusions: In line with previous lab studies, making eye movements was more taxing than eyes fixed. We discuss why this effect was not observed for reductions in PTSD symptoms in the clinical trial (e.g., differences in dependent variables, sample population, and intervention duration). For more comprehensive future insights, we recommend integration of mechanistically focused lab analogue studies and patient-oriented clinical studies.
KW - Cognitive load
KW - Divided attention
KW - Eye movement desensitization and reprocessing
KW - Working memory
UR - http://www.scopus.com/inward/record.url?scp=85070215281&partnerID=8YFLogxK
U2 - 10.1016/j.jbtep.2019.101494
DO - 10.1016/j.jbtep.2019.101494
M3 - Article
C2 - 31401457
AN - SCOPUS:85070215281
SN - 0005-7916
VL - 65
JO - Journal of Behavior Therapy and Experimental Psychiatry
JF - Journal of Behavior Therapy and Experimental Psychiatry
M1 - 101494
ER -