Social information use across the lifespan

Social information shapes how humans learn, decide, and coordinate. Theory predicts that social information is most valuable early in life, but how social information use changes across the lifespan remains poorly understood. Across seven belief-updating experiments with museum samples from Germany and Japan (ages 6–99 years; N = 41,015), we find a robust age-related trajectory: Social information use is highest early in life, drops sharply until late adolescence, and then rises slowly into late adulthood. Participants at all ages used social information most when it was close to their own belief, supported by convergent social inputs, and came from young adults. Female participants used slightly more social information than male participants, and participants from Germany used more social information than those from Japan. Together, these results reveal early-emerging strategic social information use and help explain information flow in age-diverse populations.