Nodding and shaking of the head as simulated approach and avoidance responses

Abstract

Simulation of vertical and horizontal head movements during semantic and affective evaluation of linguistic stimuli is investigated in explicit and implicit tasks. • Motion detection software is implemented to allow participants to assess the stimuli with head movements. • Accepted stimuli were evaluated faster with vertical head movements and refused stimuli with horizontal head movements. • Semantic evaluation activated the simulation of the vertical and horizontal head movements as gestures having a communicative function "for the other", whilst affective evaluation activated their simulation as approach and avoidance responses "for the self". • The greater the affective valence of the stimulus, the more implicit and automatic the simulation. Nodding and shaking of the head as simulated approach and avoidance responses

Ghost on the Windshield: Employing a Virtual Human Character to Communicate Pedestrian Acknowledgement and Vehicle Intention

“…Very similar to emotional facial expressions, conversational facial expressions, such as the nod and the head shake, are widely recognized across cultures too, and provide the perceiver with information about the expresser's cognitive state and intentions [101][102][103]. More specifically, in the context of social interaction, a nod communicates agreement or cooperativeness, whereas a head shake communicates disagreement or unwillingness to cooperate [104][105][106][107][108][109].…”

“…In that case, the pedestrian would make the association between disagreement/unwillingness to cooperate and denying passage and would thus not proceed to cross the street in front of the oncoming vehicle. Furthermore, all three expressions-angry, surprised, and head shake-are social stimuli that elicit an avoidance tendency in the perceiver due to the presumed costs of interacting with an individual that exhibits the negative qualities assigned to said facial expressions [99,100,108,109,111,[118][119][120][121]. In the context of traffic interaction, this tendency would translate to an intention on the part of the pedestrian not to cross the street in front of the oncoming vehicle.…”

Smiles and Angry Faces vs. Nods and Head Shakes: Facial Expressions at the Service of Autonomous Vehicles

“…Conversational facial expressions, such as the nod and the head shake, are universally utilized for providing information about an expresser's cognitive state and intentions [102][103][104]. For instance, during social interactions, a nod is produced to communicate agreement or cooperativeness, whereas a head shake is produced to communicate disagreement or unwillingness to cooperate [105][106][107][108][109][110]. Fittingly, a driver could also decide to nod at a pedestrian to let them know they will be yielded to [1,3,4].…”