A portable device for collecting information about a human body is adapted to be worn on the human body and is capable of periodically performing cognitive faculty tests during daily life to discern fluctuations in the memory faculty of a wearer. The device displays a problem of cognitive tests on a display unit, and a wearer inputs an answer with an input unit. The wearer's response time is clocked with a clock unit, and the answer and the response time are stored in a memory unit in time sequence by control of a control circuit. The device can include a detection unit for detecting a living body signal to enable research on the relationship between behavioral patterns or temperamental trends and memory faculties, and the like.