This investigation studied the effects of transcranial direct current stimulation (tDCS) on the Attention Network Task (ANT) - a combination speeded response/flanker task, which elucidates activity of three attentional networks - alerting, orienting, and executive functioning. Anodal tDCS was applied over the right inferior frontal cortex at 0.1 mA or 2.0 mA for 30 minutes. Participants were tested prior to stimulation, roughly 30 minutes following cessation of stimulation, 70 minutes following cessation of stimulation, and 115 minutes following cessation of stimulation. Due to the areas being stimulated (RIFC), and results from previous studies that link the alerting network to frontal and parietal activation (Coull et al., 2001), and executive control function to the ACC and the lateral prefrontal cortex (Bush et al., 2000), it seemed reasonable that higher scores for these networks will be achieved by those in the active stimulation groups. However, the only network difference observed involved the alerting network, in an unexpected direction (higher scores for the sham group). The active group (2.0mA stimulation), while obtaining smaller differences in RT between conditions, responded faster across all conditions. These results, however, were rendered non-significant due to group differences observed at the baseline measure. It is possible the RT scores related to levels of concentration, though a third variable could be the root of observed differences. Thus, results are inconclusive given the current set of data.
Level of Degree
Clark, Dr. Vincent P.
First Committee Member (Chair)
Goldsmith, Dr. Tim
Second Committee Member
Hodge, Dr. Gordon
Attention--Physiological aspects, Brain--Electric properties, Brain stimulation, Electrophysiology.
Trumbo, Michael. "Effect of transcranial direct current stimulation on the Attention Network Task (ANT)." (2012). http://digitalrepository.unm.edu/psy_etds/139