TY - JOUR
T1 - Visual expertise does not predict the composite effect across species
T2 - a comparison between spider (Ateles geoffroyi) and rhesus (Macaca mulatta) monkeys
AU - Taubert, Jessica
AU - Parr, Lisa A.
PY - 2009
Y1 - 2009
N2 - Humans are subject to the composite illusion: two identical top halves of a face are perceived as “different” when they are presented with different bottom halves. This observation suggests that when building a mental representation of a face, the underlying system perceives the whole face, and has difficulty decomposing facial features. We adapted a behavioural task that measures the composite illusion to examine the perception of faces in two nonhuman species. Specifically we had spider (Ateles geoffroyi) and rhesus monkeys (Macaca mulatta) perform a two-forced choice, match-to-sample task where only the top half of sample was relevant to the task. The results of Experiment 1 show that spider monkeys (N = 2) process the faces of familiar species (conspecifics and humans, but not chimpanzees, sheep, or sticks), holistically. The second experiment tested rhesus monkeys (N = 7) with the faces of humans, chimpanzees, gorillas, sheep, and sticks. Contrary to prediction, there was no evidence of a composite effect in the human (or familiar primate) condition. Instead, we present evidence of a composite illusion in the chimpanzee condition (an unfamiliar primate). Together, these experiments show that visual expertise does not predict the composite effect across the primate order.
AB - Humans are subject to the composite illusion: two identical top halves of a face are perceived as “different” when they are presented with different bottom halves. This observation suggests that when building a mental representation of a face, the underlying system perceives the whole face, and has difficulty decomposing facial features. We adapted a behavioural task that measures the composite illusion to examine the perception of faces in two nonhuman species. Specifically we had spider (Ateles geoffroyi) and rhesus monkeys (Macaca mulatta) perform a two-forced choice, match-to-sample task where only the top half of sample was relevant to the task. The results of Experiment 1 show that spider monkeys (N = 2) process the faces of familiar species (conspecifics and humans, but not chimpanzees, sheep, or sticks), holistically. The second experiment tested rhesus monkeys (N = 7) with the faces of humans, chimpanzees, gorillas, sheep, and sticks. Contrary to prediction, there was no evidence of a composite effect in the human (or familiar primate) condition. Instead, we present evidence of a composite illusion in the chimpanzee condition (an unfamiliar primate). Together, these experiments show that visual expertise does not predict the composite effect across the primate order.
KW - Comparative psychology
KW - Face perception
KW - Holistic processing
U2 - 10.1016/j.bandc.2009.09.002
DO - 10.1016/j.bandc.2009.09.002
M3 - Article
C2 - 19815323
SN - 0278-2626
VL - 71
SP - 187
EP - 195
JO - Brain and Cognition
JF - Brain and Cognition
IS - 3
ER -