Sex and the stimulus-movement effect: Differences in acquisition of autoshaped responding in cynomolgus monkeys

Abstract

The stimulus-movement effect refers to the phenomenon in which stimulus discrimination or acquisition of a response is facilitated by moving stimuli as opposed to stationary stimuli. The effect has been found in monkeys, rats, and humans, but the experiments conducted did not provide adequate female representation to investigate potential sex differences. The current experiment analyzed acquisition of stimulus touching in a progressive series of classical conditioning procedures in cynomolgus monkeys (Macaca fascicularis) as a function of sex and stimulus movement. Classical conditioning tasks arrange two or more stimuli in relation to each other with different temporal and predictive relations. Autoshaping procedures overlay operant contingencies onto a classical-conditioning stimulus arrangement. In the present case, a neutral stimulus (a small gray square displayed on a touchscreen) functioned as the conditional stimulus and a food pellet functioned as the unconditional stimulus. Although touching is not required to produce food, with repeated stimulus pairings subjects eventually touch the stimulus. Across conditions of increasing stimulus correlation and temporal contiguity, male monkeys acquired the response faster with a moving stimulus. In contrast, females acquired the response faster with a stationary stimulus. These results demonstrate that the stimulus-movement effect may be differentially affected by sex and indicate that additional experiments with females are needed to determine how sex interacts with behavioral phenomena discovered and elaborated almost exclusively using males.

Group-based, autonomous, individualized training and testing of long-tailed macaques (Macaca fascicularis) in their home enclosure to a visuo-acoustic discrimination task

“…Our results suggest that long-tailed macaques can be trained in an automated manner to perform basic visually guided tasks using a touchscreen system but failed to generalize to an acoustically guided 2 AC task. These findings are in line with previous reports that showed that long-tailed macaques could perform a stimulus-directed touch behavior using a touchscreen system engaging consistently over several sessions ( Bullock and Myers, 2009 ; Rice et al, 2017 ). However, previous reports have shown that macaques ( Macaca fascicularis , Macaca fuscata , and Macaca nemestrina ) are indeed able to solve acoustic discrimination tasks ( Kuhl and Padden, 1983 ; Petersen et al, 1984 ; Brosch et al, 2004 ; Furuyama et al, 2017 ).…”

Touchscreen technology in the study of cognition-related behavior

“…This second generation touchscreen methodology allows for an experimental interface with maximal control over all parameters of traditional cognitive tasks and, also, the possibility of creating novel translational tasks (e.g., Daniel and Katz, 2016; Hutsell and Banks, 2015; Kangas and Bergman, 2012; Rice et al, 2017). The advantages of this approach are readily apparent, for example, in work to identify and capture key features of novel behavioral phenotypes.…”