Research Reports - Cumulative effects of transcranial direct current stimulation on attention/working memory after traumatic brain injury
Clin Neurophysiol. 2015 Mar;126(3):486-96
Ulam F(1), Shelton C(2), Richards L(2), Davis L(2), Hunter B(2), Fregni F(2),
OBJECTIVE: To investigate in a randomized, double-blind design, cumulative
effects of anodal tDCS on EEG oscillations and neuropsychological tests among
patients with traumatic brain injury (TBI) undergoing subacute
METHODS: Twenty-six patients were randomly assigned to active (n=13) or sham
(n=13) tDCS groups. EEGs were recorded at 6 different time points, assessing both
immediate and cumulative effects of tDCS on EEG oscillations. Twenty minute
sessions of 1mA anodal stimulation to the left dorsolateral prefrontal cortex
(F3, cathode placed at right supraorbital site, Fp2), were provided on 10
consecutive days. Neuropsychological tests were administered before and after the
series of tDCS sessions.
RESULTS: Theta was significantly reduced for active tDCS patients following the
first tDCS session. Delta decreased and alpha increased, both significantly, for
the active tDCS group after 10 consecutive tDCS sessions. No significant changes
were seen for sham group. Decreases in delta were significantly correlated with
improved performance on neuropsychological tests for the active tDCS group to far
greater degree than for the sham group. Participants in the active tDCS group who
had excess slow EEG activity in their initial recordings showed greater
improvement on neuropsychological tests than other groups.
CONCLUSION: Results suggest that 10 anodal tDCS sessions may beneficially
modulate regulation of cortical excitability for patients with TBI.
SIGNIFICANCE: EEG-guided tDCS warrants further investigation as a potential
intervention for TBI during subacute neurorehabilitation.