Enhancement of object detection with transcranial direct current stimulation is associated with increased attention
1 The Department of Psychology, University of New Mexico, MSC03-2220, Albuquerque, NM 87131-1161, USA
2 The Department of Neurosciences, University of New Mexico, MSC08-4740, Albuquerque, NM 87131-5223, USA
3 Clinical Neuroscience Center, Dept. Psychology, University of New Mexico, MSC03-2220, Albuquerque, NM 87131-1161, USA
4 The Mind Research Network and Lovelace Respiratory Research Institute, 1101 Yale NE, Albuquerque, NM 87106, USA
BMC Neuroscience 2012, 13:108 doi:10.1186/1471-2202-13-108Published: 10 September 2012
We previously found that Transcranial Direct Current Stimulation (tDCS) improves learning and performance in a task where subjects learn to detect potential threats indicated by small target objects hidden in a complex virtual environment. In the present study, we examined the hypothesis that these effects on learning and performance are related to changes in attention. The effects of tDCS were tested for three forms of attention (alerting, orienting, and executive attention) using the Attention Network Task (ANT), which were compared with performance on the object-learning task.
Participants received either 0.1 mA (N = 10) or 2.0 mA (N = 9) tDCS during training and were tested for performance in object-identification before training (baseline-test) and again immediately after training (immediate test). Participants next performed the Attention Networks Task (ANT), and were later tested for object-identification performance a final time (delayed test). Alerting, but not orienting or executive attention, was significantly higher for participants receiving 2.0 mA compared with 0.1 mA tDCS (p < 0.02). Furthermore, alerting scores were significantly correlated with the proportion of hits (p < 0.01) for participants receiving 2.0 mA.
These results indicate that tDCS enhancement of performance in this task may be related in part to the enhancement of alerting attention, which may benefit the initial identification, learning and/or subsequent recognition of target objects indicating potential threats.