Fig. 3: GSR results (n = 32) by level of interest.

Box plots show the distribution of A mean tonic activity and B mean phasic activity (x10) in microsiemens, for lecture segments rated as high vs. low in interest. The mean phasic activity is shown as a representative phasic measure, as all phasic metrics showed similar effects. In both panels, red lines indicate the median, boxes represent the IQR, whiskers extend to 1.5×IQR, and individual dots represent participants’ data points.