Improvement of Memory and Spatial Cognitive Function by Continuous Ingestion of 100mg/day of γ—Aminobutyric Acid(GABA)―A Randomized, Double—blind, Placebo—controlled Parallel—group Clinical Trial― Atsushi Yamatsu and et al., 薬理と治療, 48, 475-486 (2020), DOI:http://dx.doi.org/