Anodal transcranial direct current stimulation over the left dorsolateral prefrontal cortex modulates attention and pain in fibromyalgia: randomized clinical trial

Adriana Ferreira Silva,Maxciel Zortea,Wolnei Caumo,Iraci Lucena Da Silva Torres,Felipe Fregni,Jorge Leite,Sandra Carvalho

doi:10.1038/s41598-017-00185-w

Abstract

Cognitive dysfunction in fibromyalgia patients has been reported, especially when increased attentional demands are required. Transcranial direct current stimulation (tDCS) over the dorsolateral prefrontal cortex (DLPFC) has been effective in modulating attention. We tested the effects of a single session of tDCS coupled with a Go/No-go task in modulating three distinct attentional networks: alertness, orienting and executive control. Secondarily, the effect on pain measures was evaluated. Forty females with fibromyalgia were randomized to receive active or sham tDCS. Anodal stimulation (1 mA, 20 min) was applied over the DLPFC. Attention indices were assessed using the Attention Network Test (ANT). Heat pain threshold (HPTh) and tolerance (HPTo) were measured. Active compared to sham tDCS led to increased performance in the orienting (mean difference [MD] = 14.63) and executive (MD = 21.00) attention networks. There was no effect on alertness. Active tDCS increased HPTh as compared to sham (MD = 1.93) and HPTo (MD = 1.52). Regression analysis showed the effect on executive attention is mostly independent of the effect on pain. DLPFC may be an important target for neurostimulation therapies in addition to the primary motor cortex for patients who do not respond adequately to neurostimulation therapies.

Highlights

In addition to pain, cognitive impairments are reported in more than 70% of subjects with FM6, 7
Anterior cingulate and other cortical left and right frontal areas are activated when Executive control of attention is performed[13]. This anatomo-clinical relationship creates an opportunity to investigate the effect of non-invasive brain stimulation techniques, such as transcranial direct current stimulation
We investigate the effects of transcranial direct current stimulation (tDCS) over the dorsolateral prefrontal cortex (DLPFC) coupled with a Go/No-go Task in modulating three distinct attentional networks: alert, orienting and executive control

Summary

Introduction

Cognitive impairments are reported in more than 70% of subjects with FM6, 7. Anterior cingulate and other cortical left and right frontal areas are activated when Executive control of attention is performed[13] This anatomo-clinical relationship creates an opportunity to investigate the effect of non-invasive brain stimulation techniques, such as transcranial direct current stimulation (tDCS). In healthy subjects tDCS over the dorsolateral prefrontal cortex (DLPFC) increased pain threshold[15] and in patients with fibromyalgia it relieved chronic pain[16, 17] This technique has been effectively used to enhance cognitive functions, in both healthy[18,19,20] and clinical populations[21, 22]. The neuromodulation of one component of the pain neuromatrix will lead to changes in pain measurements

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Conclusion