Related Experiment Video
Updated: Sep 28, 2025

Perceptual and Category Processing of the Uncanny Valley Hypothesis' Dimension of Human Likeness: Some Methodological Issues
Published on: June 3, 2013
Children (Homo sapiens), but not rhesus monkeys (Macaca mulatta), perceive the one-is-more illusion
Emma J McKeon1, Michael J Beran1, Audrey E Parrish1
1Department of Psychology.
Abstract:
Visual illusions are of particular interest to cognitive researchers because they reflect the active role of the brain in processing the world around us. Yousif and Scholl (2019) recently described a new visual experience, the one-is-more illusion, in which adult humans perceived continuous objects as longer than sets of discrete objects of equal length. In the current study, we investigated this phenomenon in human children (Homo sapiens) and rhesus macaques (Macaca mulatta). Children were presented with a computerized 2-choice discrimination task and successfully selected the longer of 2 images for control trials. On trials in which 2 versions of the same image were presented (identical in length), and one was of a continuous form and the other consisted of 2 or more distinct units, children showed a bias for the continuous object. Monkeys were given the same computerized task and learned to choose the longer of 2 otherwise identical stimuli. However, monkeys did not show a bias to choose the continuous probe images as longer than the discrete images in the critical test trials with equal-length stimuli. These results are discussed in light of developmental and comparative research on related illusory experiences and perceptual mechanisms. (PsycInfo Database Record (c) 2022 APA, all rights reserved).
More Related Videos
08:42Assessment of Social Cognition in Non-human Primates Using a Network of Computerized Automated Learning Device ALDM Test Systems
Published on: May 5, 2015
06:25Analysis of Simian Immunodeficiency Virus-specific CD8+ T-cells in Rhesus Macaques by Peptide-MHC-I Tetramer Staining
Published on: December 23, 2016
Related Concept Videos
Nonconscious Mimicry
Causes of Similarity-Dissimilarity Effect
Perceptual Constancy
Size constancy is the recognition that an object remains the same size, even when its image on the retina changes. For instance, a bus is perceived to be large enough to carry people, even if it looks tiny from...
The Representativeness Heuristic
Cognitive Learning
E. C. Tolman's theory of purposive behavior emphasizes that much behavior is goal-directed. He argued that to understand behavior, we must look at the entire sequence of actions leading to a goal. For instance, high school students study hard, not just due to past reinforcement but also to achieve the goal of getting into a good college.
Tolman introduced the idea that behavior is influenced by...