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Published March 2025 | Version Published
Journal Article Open

Effects of noninvasive neuromodulation combined with rapid, short-duration self-image stimuli in body dysmorphic disorder

Creators

  • 1. ROR icon Hong Kong University of Science and Technology
  • 2. ROR icon Massachusetts General Hospital
  • 3. ROR icon Harvard University
  • 4. ROR icon University of Toronto
  • 5. ROR icon Centre for Addiction and Mental Health
  • 6. ROR icon La Trobe University
  • 7. ROR icon University of California, Los Angeles
  • 8. ROR icon California Institute of Technology
  • 9. ROR icon Karolinska Institute

Abstract

Body dysmorphic disorder (BDD) is characterized by distressing and impairing preoccupations with misperceived appearance defects [1]. Previous studies demonstrate reduced global and enhanced detailed visual processing, with converging findings from neuroimaging studies showing reduced brain activation and connectivity in the dorsal visual stream (DVS) and enhanced ventral visual stream (VVS) activity [2]. This has led to a theory of imbalances in global versus detailed visual processing in BDD, which may confer perceptual distortions. As misperception of one's appearance is a core phenomenological feature in BDD, a mechanistic understanding of if, and how, visual systems can be modulated could inform the rational development of novel treatments.
We previously reported a proof-of-concept study in which intermittent theta-burst (iTBS) repetitive Transcranial Magnetic Stimulation (rTMS) was administered to the lateral parietal cortex in individuals with BDD with face concerns. This enhanced dynamic effective connectivity (DEC) [3] in the DVS when viewing their face [4]. Separately, we tested the effects of rapid, short duration own-face presentation in those with BDD with face concerns and in healthy controls (CON) [5]. In the DVS, magnocellular pathways are tuned to rapid image presentation [6,7], facilitating global/holistic visual processing. In the VVS, conversely, rapid image presentation with shorter stimulus duration is associated with reduced activation magnitude [[7], [8], [9]]. Therefore, rapid, short-duration stimuli may enhance DVS and reduce VVS function, which might alter the balance between global and local visual processing. However, rapid, short presentation stimuli compared with long, slow presentation resulted in no significant DEC effect in BDD in the DVS; in the VVS, it reduced DEC in healthy controls, but only at trend-level in BDD(5).
Given the effects of these separate strategies, this analysis tested the combined effects of iTBS over DVS parietal cortical targets and rapid face presentation on visual system connectivity. We hypothesized that high-intensity (100 % active motor threshold - AMT) iTBS followed by repeated short-duration face presentation would result in stronger DVS positive effective connectivity compared with low-intensity stimulation (10 % AMT – the control condition, planned as “sham”). We focused on anterior connections in the DVS (“DVSHigher”; Fig. 1b), which demonstrates clinical relevance in BDD as evidenced by a significant negative correlation between Yale-Brown Obsessive-Compulsive Scale Modified for BDD scores and DEC for DVSHigher in a previous study [10].

Copyright and License

© 2025 The Authors. Published by Elsevier Inc. Under a Cretaive COmons license, CC BY-NC-ND 4.0.

Acknowledgement

This research was supported by NIH grants (R21MH110865, R01MH121520, and R21MH128815 to JDF), the NIH National Center for Advancing Translational Science (NCATS) UCLA CTSI (UL1TR001881 to JDF), and funding from the Nathan Cummings Foundation (JDF). We thank all participants for their involvement in the study.

Supplemental Material

  • Multimedia component 1.

Contributions

Wan-wa Wong: Formal analysis, Visualization, Writing – original draft, Writing – review & editing. D. Rangaprakash: Conceptualization, Methodology, Writing – review & editing. Joel P. Diaz-Fong: Investigation, Writing – review & editing. Hayden J. Peel: Visualization, Writing – original draft, Writing – review & editing. Reza Tadayonnejad: Conceptualization, Investigation, Writing – review & editing. Andrew F. Leuchter: Conceptualization, Methodology, Writing – review & editing, Investigation, Resources, Supervision. Jamie D. Feusner: Conceptualization, Investigation, Methodology, Project administration, Resources, Supervision, Writing – original draft, Writing – review & editing.

Conflict of Interest

The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: Jamie Feusner reports financial support was provided by National Institute of Mental Health. Jamie Feusner reports financial support was provided by National Center for Advancing Translational Sciences. Jamie Feusner reports financial support was provided by Nathan Cummings Foundation. If there are other authors, they declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.

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Additional details

Funding

National Institutes of Health
R21MH110865
National Institutes of Health
R01MH121520
National Institutes of Health
R21MH128815
National Center for Advancing Translational Sciences
UCLA CTSI UL1TR001881
Nathan Cummings Foundation

Dates

Accepted
2025-02-20
Accepted
Available
2025-02-22
Published online
Available
2025-02-27
Version of Record online

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Published