In contrast, induced θ oscillations 300 to 500 ms following the target stimulus are significantly enhanced in LTAAs compared to NACs. The group effect is specific to target detection. After removing variance of the pre-stimulus θ power and the P3b amplitude from the induced θ power, the group effect, although reduced in size, is still significant. This indicates that the induced θ oscillations, independent of pre-stimulus θ power levels, significantly discriminate the groups. Also, these induced θ oscillations are independent measures of group discrimination to the P3b amplitude measure. Furthermore, comparison of effect sizes show that induced θ oscillations that index target stimulus processing are more sensitive measures of group membership than baseline θ power measures that index general levels of attention and motivation during task performance.
