A head-mounted display (HMD) device includes a plurality of activity detection sensors coupled to a liner formed around a periphery of a HMD or a band attached to the HMD. The sensors attached to the liner are adopted for direct or indirect contact to an upper portion of a users face, and the sensors coupled to the band are adopted for direct or indirect contact with a back side of the users head. The activity detection sensors detect electrical field signals caused by muscle contractions in an upper portion of a users face or brain activity signals when the user is wearing the HMD. The HMD includes a module that reconstructs and projects a facial animation model of the user and a cognitive state of the user based on signals from the activity detection sensors while the HMD is in use by the user.