TY - JOUR T1 - A naturalistic dynamic monkey head avatar elicits species-typical reactions and overcomes the uncanny valley JF - eneuro JO - eNeuro DO - 10.1523/ENEURO.0524-19.2020 SP - ENEURO.0524-19.2020 AU - Ramona Siebert AU - Nick Taubert AU - Silvia Spadacenta AU - Peter W. Dicke AU - Martin A. Giese AU - Peter Thier Y1 - 2020/06/08 UR - http://www.eneuro.org/content/early/2020/06/08/ENEURO.0524-19.2020.abstract N2 - Research on social perception in monkeys may benefit from standardized, controllable, and ethologically valid renditions of conspecifics offered by monkey avatars. However, previous work has cautioned that monkeys, like humans, show an adverse reaction toward realistic synthetic stimuli, known as the “uncanny valley” effect. We developed an improved naturalistic rhesus monkey face avatar capable of producing facial expressions (fear grin, lip smack and threat), animated by motion capture data of real monkeys. For validation, we additionally created decreasingly naturalistic avatar variants. Eight rhesus macaques were tested on the various videos and avoided looking at less naturalistic avatar variants, but not at the most naturalistic or the most unnaturalistic avatar, indicating an uncanny valley effect for the less naturalistic avatar versions. The avoidance was deepened by motion and accompanied by physiological arousal. Only the most naturalistic avatar evoked facial expressions comparable to those toward the real monkey videos. Hence, our findings demonstrate that the uncanny valley reaction in monkeys can be overcome by a highly naturalistic avatar.SIGNIFICANCE STATEMENTWe introduce a new, naturalistic monkey avatar and validate it as an appropriate stimulus for studying primate social cognition by demonstrating that it elicits natural looking patterns and facial reactions in macaque monkeys rather than evoking an “uncanny” avoidance reaction. The fact that a degraded version of the avatar is able to evoke an uncanniness reaction confirms its existence in monkeys, supporting an evolutionary old behavioral commonality shared by monkeys and man. However, as this reaction can be overcome by a very naturalistic avatar, the uncanny valley is clearly not an inevitable consequence of high degrees of realism. ER -