A target authentication device includes an electrode to detect an electrical signal associated with a user of the device. The electrical signal represents an authentication code for the device. An authentication receiver module is coupled to the electrode. The module receives the electrical signal from the electrode and determines whether the electrical signal matches a predetermined criterion to authenticate the identity of the user based on the electrical signal. An authentication module is also disclosed. The authentication module includes one electrode to couple an electrical signal associated with a user to a user of a target authentication device, the electrical signal represents an authentication code for the device. An authentication transmission module is coupled to the electrode. The authentication transmission module transmits the electrical signal from the electrode. A method of authenticating the identity of a user of a target authentication device also is disclosed.