The generation effect in monkeys
Related Experiment Video
Updated: Jul 13, 2026

Assessment of Social Cognition in Non-human Primates Using a Network of Computerized Automated Learning Device (ALDM) Test Systems
Published on: May 5, 2015
Nate Kornell1, Herbert S Terrace
1Department of Psychology, University of California, Los Angeles, CA 90095-1563, USA. nkornell@psych.ucla.edu
Abstract:
How well one retains new information depends on how actively it is processed during learning. Active attempts to retrieve information from memory result in more learning than passive observation of the same information (the generation effect). Here, we present evidence for the generation effect in monkeys. Subjects were trained to respond to five-item lists of photographs in a particular order. On some lists, they could request "hints" to guide their behavior; on others, they had to generate the correct order from memory. Training with hints resulted in high levels of initial performance, but accuracy dropped precipitously when the hints were removed on the criterion test. Training without hints led to relatively poor initial performance, but accuracy increased steadily and remained high on the criterion test.
Related Concept Videos
Background and Environment Affect Phenotype
An example of how genetic background affects phenotype can be seen in horses. The Extension gene in horses is responsible for their coat color. A wild-type gene (EE) produces black pigment in the coat, while a mutant gene (ee) produces red pigment. A...
Life Histories

