In this study, we investigated the influence of background music on work efficiency from the perspectives of biological data and subjective evaluations from the study participants. Biological data was obtained by measuring cerebral blood flow, while participants' subjective evaluations were garnered via a questionnaire using the Visual Analog Scale (VAS). The data collected were subjected to analyses using basic statistics, correlation coefficients, graphical plots, and t-tests to ascertain significant differences. Our results indicated that the number of correct answers and cerebral blood flow in the left frontal region significantly increased when participants performed calculation tasks while listening to background music.