The aims of this study were to examine whether a portable wireless functional near-infrared spectroscopy device ([fNIRS] Hb-13-2, Astem Co., Ltd., Kanagawa, Japan) could potentially be used as a simple and minimally burdensome tool for screening cognitive function in older adults, particularly for identifying dementia-related changes, and to explore the feasibility of establishing a methodological framework for such assessment. Here, GSTM1 is linked to dementia.