PC-compatible computer-generated stimuli for video-task testing

A computer touch screen system and training procedure for use with primate infants: Results from pigtail monkeys (Macaca nemestrina)

Computerized cognitive and perceptual testing has resulted in many advances towards understanding adult brain-behavior relations across a variety of abilities and species. However, there has been little migration of this technology to the assessment of very young primate subjects. We describe a training procedure and software that was developed to teach infant monkeys to interact with a touch screen computer. Eighteen infant pigtail macaques began training at 90-postnatal days and five began at 180-postnatal days. All animals were trained to reliably touch a stimulus presented on a computer screen and no significant differences were found between the two age groups. The results demonstrate the feasibility of using computers to assess cognitive and perceptual abilities early in development.

Rhesus monkeys (Macaca mulatta) immediately generalize the uncertain response

Rhesus monkeys (Macaca mulatta) have learned, like humans, to use an uncertain response adaptively under test conditions that create uncertainty, suggesting a metacognitive process by which human and nonhuman primates may monitor their confidence and alter their behavior accordingly. In this study, 4 rhesus monkeys generalized their use of the uncertain response, without additional training, to 2 familiar tasks (2-choice discrimination learning and mirror-image matching to sample) that predictably and demonstrably produce uncertainty. The monkeys were significantly less likely to use the uncertain response on trials in which the answer might be known. These results indicate that monkeys, like humans, know when they do not know and that they can learn to use a symbol as a generalized means for indicating their uncertainty.

Testing primates with joystick-based automated apparatus: lessons from the Language Research Center's Computerized Test System

Nonhuman primates provide useful models for studying a variety of medical, biological, and behavioral topics. Four years of joystick-based automated testing of monkeys using the Language Research Center's Computerized Test System (LRC-CTS) are examined to derive hints and principles for comparable testing with other species--including humans. The results of multiple parametric studies are reviewed, and reliability data are presented to reveal the surprises and pitfalls associated with video-task testing of performance.

Lateralized changes in tympanic membrane temperature in relation to different cognitive tasks in chimpanzees (Pan troglodytes)

Lateralized changes in tympanic membrane (TM) temperature were assessed in chimpanzees. Subjects were engaged in 1 of 3 different cognitive tasks, including matching-to-sample, visual-spatial discrimination, and a motor task. During execution of each task, TM temperatures were taken from each ear over a 20-min time period. The TM temperatures at each time interval were subtracted from a baseline measure to assess relative change in blood flow. For the matching-to-sample and visual-spatial discrimination tasks, significant lateralized changes in TM temperature were found, with left-ear temperature increasing and right-ear temperature decreasing. No laterality effects were found for the motor or control tasks. These data provide the first evidence of laterality in physiological functioning in chimpanzees and suggest that transient asymmetries in cognitive functions are associated with changes in cerebral blood flow as assessed by TM temperature change.