Figure 2. Experiment Design. Baseline fNIRS was recorded for 30 s at the beginning of each experiment. Then, a fixation point was shown for 0.5 s, followed by a presentation of a randomly chosen sentence for 4 s. Subsequently, there was a 3-second long response window, during which the question was presented on the screen and the subjects had to give a response. Each trial concludes with an interstimulus interval chosen randomly within the range of 7-10 seconds.