A comprehension-level calculation device that calculates a comprehension level of a user to sound language, retains respective time series of pieces of biological information in a plurality of regions of the user during presentation of the sound language to the user, calculates a similarity level for each pair of the time series, calculates the comprehension level on the basis of the calculated similarity level, and determines, in a case where the calculated similarity level is higher, the comprehension level as a higher value in the calculation of the comprehension level.
COMPREHENSION-LEVEL CALCULATION DEVICE AND COMPREHENSION-LEVEL CALCULATION METHOD