Fig. 7From: Functional near-infrared spectroscopy can detect low-frequency hemodynamic oscillations in the prefrontal cortex during steady-state visual evoked potential-inducing periodic facial expression stimuli presentationThe frequency domain grand-averaged LFHO signals after deconvolution across all conditions and participants during SSVEP-inducing periodic FE stimuli presentation. The unit of the x-axis is Hz while the y-axis has no unitsBack to article page