Brain-directed interventions for eating disorders:

: The potential of repetitive transcranial magnetic stimulation in the treatment of anorexia nervosa

Abstract

Background: Advances in neuroscience have led to a deeper understanding of
the neuro-circuitry associated with eating disorders (ED). There is however, a
lack of brain-directed treatment options. Neuromodulatory techniques have
therapeutic efficacy in other psychiatric disorders and evidence in ED is
promising. There is a need for further studies of neuromodulation in ED, to
probe disease mechanisms and to develop novel treatments. The aim of this
research is to explore the use of neuromodulation in ED and specifically assess
the utility of repetitive transcranial magnetic stimulation (rTMS) in anorexia
nervosa (AN).
Methods: An overview of ED and their neurocircuitry underpinnings is
presented. A systematic review of the literature regarding the effects of
neuromodulation on eating related outcomes was also conducted. The effects of
neuronavigated (MRI-guided) rTMS in AN is explored in a single-session
randomised control trial (RCT) and in a 20-session therapeutic case series.
Results: The systematic review supports further research on neuromodulation
in ED. The single-session RCT of real versus sham rTMS in 51 individuals with
AN demonstrated that following real rTMS, individuals report reduced AN
symptoms and an increased liking of specific foods. Real/sham rTMS did not
alter salivary cortisol concentrations and levels of cortical excitability were
associated with AN symptomatology. Lastly, rTMS proved to be safe, tolerable
and acceptable in people with AN. A neurocognitive measure of intertemporal
choice showed that rTMS encourages prudent decision making in AN: this may
underlie the effects of rTMS on AN symptoms. Whilst a therapeutic case series
of five individuals with enduring AN did not lead to weight gain, significant
improvements in ED and general psychopathology were reported and
sustained.
Conclusions: rTMS has the ability to improve core symptomatology in AN and
alter decision making processes. Therefore, neuromodulation may be a viable
treatment adjunct for people with an ED.

Date of Award	2015
Original language	English
Awarding Institution	King's College London
Supervisor	Iain Campbell (Supervisor) & Ulrike Schmidt (Supervisor)