Effects of cranial electrotherapy stimulation on resting state brain activity

Abstract

Cranial electrotherapy stimulation (CES) is a U.S. Food and Drug Administration (FDA)-approved treatment for insomnia, depression, and anxiety consisting of pulsed, low-intensity current applied to the earlobes or scalp. Despite empirical evidence of clinical efficacy, its mechanism of action is largely unknown. The goal was to characterize the acute effects of CES on resting state brain activity. Our primary hypothesis was that CES would result in deactivation in cortical and subcortical regions. Eleven healthy controls were administered CES applied to the earlobes at subsensory thresholds while being scanned with functional magnetic resonance imaging in the resting state. We tested 0.5- and 100-Hz stimulation, using blocks of 22 sec “on” alternating with 22 sec of baseline (device was “off”). The primary outcome measure was differences in blood oxygen level dependent data associated with the device being on versus baseline. The secondary outcome measures were the effects of stimulation on connectivity within the default mode, sensorimotor, and fronto-parietal networks. Both 0.5- and 100-Hz stimulation resulted in significant deactivation in midline frontal and parietal regions. 100-Hz stimulation was associated with both increases and decreases in connectivity within the default mode network (DMN). Results suggest that CES causes cortical brain deactivation, with a similar pattern for high- and low-frequency stimulation, and alters connectivity in the DMN. These effects may result from interference from high- or low-frequency noise. Small perturbations of brain oscillations may therefore have significant effects on normal resting state brain activity. These results provide insight into the mechanism of action of CES, and may assist in the future development of optimal parameters for effective treatment.

Normalization of Intrinsic Neural Circuits Governing Tourette's Syndrome Using Cranial Electrotherapy Stimulation

“…Previous neuroimaging studies have claimed that CES has beneficial effects in conditions such as anxiety, depression, insomnia, stress, and pain [26], [29]. A recent functional magnetic resonance imaging (fMRI) study tested 0.5-and 100-Hz stimulation on healthy controls, using blocks of 22 s "on" alternating with 22 s of baseline (device was "off"), suggesting that CES caused cortical brain deactivation in prefrontal and parietal regions [30]. Electroencephalographic studies showed that CES increased alpha activity (increased relaxation), decreased delta activity (reduced fatigue), and decreased beta activity (decreased ruminative thoughts) [26], [31].…”

“…In this way, the current may initially stimulate afferent branches of cranial nerves. Then stimulation may be carried from branches of the facial, glossopharyngeal, and/or the vagus nerves to the brainstem, the thalamus, and finally the cortex [30]. We, therefore, hypothesized that CES could alter intrinsic brain activity and connectivity, which in turn improves the neuro dysfunction and leads to the normalization of intrinsic neural circuits governing TS.…”

Efficacy of Cranial Electrotherapy Stimulation Combined with Biofeedback Therapy in Patients with Functional Constipation

“…Stimulation may initially occur at branches of the facial, glossopharyngeal, and/or the vagus nerves that originate near the electrode placement on the earlobe, then are carried to the brainstem, the thalamus, and finally the cortex. 44 CES may cause cortical brain deactivation, producing changes similar to those produced by anxiolytic medications. 45 Clinically, drugs (including anxiolytics/anti-depressants) may have the same improvement on psychological disturbance similar to CES, but drugs can become habit forming, and also patients can develop a tolerance which results in an increasingly required dosage during treatment.…”

Modulation of Resting State Functional Connectivity of the Motor Network by Transcranial Pulsed Current Stimulation

“…This work has paved the way for numerous studies using rs-fMRI to address questions regarding efficiency and strength of numerous large-scale neuronal networks in the absence of a task and how these networks are altered by various pathology. For example, groups using rs-fMRI to measure functional connectivity (van den Heuvel and Hulshoff Pol, 2010) as an outcome measure have noted that anodal tDCS of the DLPFC altered the rs-FC within the default mode network and task positive network (Feusner et al, 2012;Keeser et al, 2011). Further, researchers noted that anodal tDCS of the right DLPFC increases rs-FC with the contralateral DLPFC but concurrently reduces short-range rs-FC in regions close to the anode following stimulation (Park et al, 2013).…”