1. An information recording device comprising acquisition means for acquiring information; measurement means for measuring bio-information of a person and/or environmental information around said person; change detection means for detecting changes in at least one of said bio-information and said environmental information measured by said measurement means; recording means; and recording controlling means for causing said recording means to record the information acquired by said acquisition means, when said change detection means detects changes in at least one of said bio-information and said environmental information:.