Abnormalities in the EEG power spectrum in bulimia nervosa, binge‐eating disorder, and obesity: A systematic review

Abstract

To provide a basis for electroencephalography (EEG) neurofeedback protocols for bulimia nervosa (BN), binge‐eating disorder (BED), and obesity, this systematic review investigates alterations in EEG‐measured brain activity, specifically frequency bands. A systematic literature search with predefined search terms yielded N = 7 studies meeting the inclusion criteria. The risk of bias was assessed for all studies. In resting‐state EEG, the beta activity was elevated in fronto‐central regions in individuals with obesity and co‐morbid BED. In food‐cue conditions, both obese individuals with and without BED showed increased beta activity, suggesting increased awareness of food cues and a heightened attentional focus towards food stimuli. The level of beta activity was positively correlated with eating disorder psychopathology in resting and food‐cue conditions. In individuals with BN, there was no evidence for altered EEG spectral power. The results indicate specific alterations in EEG‐based brain activity in individuals with BED and obesity. More high‐quality studies are needed to further confirm these findings and to transfer them into EEG‐based interventions.

The Influence of Physiological and Psychological Learning Mechanisms in Neurofeedback vs. Mental Imagery Against Binge Eating

“…Still, according to the results of the present study, physiological changes seem to play a role in this NF protocol against binge eating, linking reduced cortical arousal to less craving and less frequent binge eating episodes (Blume et al 2019 ; Parvaz et al 2011 ). This finding is also important because EEG high beta activity has seldom been the main target frequency range in NF protocols (Paquette et al 2009 ; Zotev et al 2014 ), but has instead mostly been used as a supplementary control range (Egner and Gruzelier 2001 ; Keith et al 2015 ).…”

“…Besides these methodological suggestions, the scientific rigor of RCTs on NF treatments should further be improved by preregistration of NF studies to prevent false-positive results and underreporting of negative outcomes in NF research (Ros et al 2020;Thibault et al 2018). Still, according to the results of the present study, physiological changes seem to play a role in this NF protocol against binge eating, linking reduced cortical arousal to less craving and less frequent binge eating episodes (Blume et al 2019;Parvaz et al 2011). This finding is also important because EEG high beta activity has seldom been the main target frequency range in NF protocols (Paquette et al 2009;Zotev et al 2014), but has instead mostly been used as a supplementary control range (Egner and Gruzelier 2001;Keith et al 2015).…”

“…For the NF group, the self-regulation task was the down-regulation of EEG high beta activity (23–28 Hz) as a means to reduce cortical arousal caused by cue exposure to appealing food cues (Blume et al 2019 ; Parvaz et al 2011 ). The signal was derived from a unipolar online EEG assessment ( Mindfield Mindmaster EEG ) at the vertex position (Cz), with reference and ground electrodes on the earlobes.…”

“…The rationale of these studies based on cue exposure with palatable food cues and subsequent down-regulation of dysfunctional EEG high beta activity (23–28 Hz) that is associated with tense arousal, craving, disinhibition, and dysfunctional eating behaviors. Changes in this brain activity range have been shown to be associated with exposure to appealing cues in eating behavior and addiction research (for reviews, see: Blume et al, 2019 ; Parvaz et al 2011 ). While EEG high beta activity has been added as a supplementary spectral range to control hyperarousal (e.g., Egner and Gruzelier, 2001 ; Keith et al 2015 ; Rostami et al 2012 ), it has seldom been the main target of regulation in NF protocols.…”

Neuropsychological and Neurophysiological Indicators of General and Food-Specific Impulsivity in Children with Overweight and Obesity: A Pilot Study

“…During the last decades, an increasing number of studies focused on the neuronal basis of obesity, mostly based on functional magnet resonance imaging or electroencephalography (EEG, for reviews see References [1,2,3]). Consistently, neuroimaging studies revealed altered neurophysiological processes in the orbitofrontal cortex [4,5,6], a region crucial for reward and reinforcement processes [7], and the dorsolateral prefrontal cortex, which is known to be involved in cognitive control [8,9,10], particularly in the processing of food cues [11].…”