Figure 1.

Cognitive performance in the delayed match-to-sample (DMS) memory task was improved after transcranial infrared stimulation to the right forehead. The DMS task involves presentation of a visual stimulus (grid pattern) on a screen. Then the stimulus disappears, and the participant must remember the stimulus through a delay. Then two choices appear, and the participant must decide which of these two is identical to the previous stimulus (the “match”). Treated subjects showed faster memory retrieval (left panel) and increased number of correct trials (right panel) out of 30 trials when attempting to choose the correct grid pattern. The function of frontal cortex regions, implicated in the attentional mode network utilized during this visuospatial memory task, was augmented by the laser treatment. Compared to baseline, this treatment also increased by 5% the oxyhemoglobin concentration of the prefrontal cortex as measured by near-infrared spectroscopy, both during the laser stimulation and during post-treatment DMS performance (in preparation). The data for the treated group consisted of n = 10 males and n = 10 females; the control group also consisted of n = 10 males and n = 10 females. ^*Significant treatment by pre-post score interaction, p < 0.05.