The invention relates to a method for determining vital parameters of a human body by means of a device (10) with at least one optical recording unit (11) and a computing unit (12), said method comprising the following steps: recording a sequence of individual image data of a single limited area of the skin (30) of the human body by means of the optical recording unit (11) evaluating the image data, including determining a pulse wave transit time and determining vital parameters of the human body from the image data by means of the computing unit (12). The invention further relates to a device for determining vital parameters. In addition, the invention relates to a method for authenticating a person and to a method for identifying a reaction of a person.
