Cognitive and motor aging in female chimpanzees

Area of Science:

• Primate cognition
• Animal aging studies
• Comparative psychology

Background:

• Longitudinal studies on aging in non-human primates are scarce.
• Understanding cognitive and motor aging in chimpanzees provides insights into primate evolution and aging processes.

Purpose of the Study:

• To investigate longitudinal cognitive and motor aging in chimpanzees (Pan troglodytes).
• To assess age-related changes in physical and social cognition, and fine motor skills.

Main Methods:

• Thirty-eight adult female chimpanzees (10-54 years old) were tested over 3 years.
• A modified Primate Cognition Test Battery assessed physical and social cognition.
• A fine motor task evaluated skill acquisition on a nut-and-rod apparatus.

Main Results:

• Little age-related decline in physical cognition; performance often stable or improved with practice.
• Significant spatial memory decline in chimpanzees over 50 years old.
• Poorer performance in social cognition tasks (attention-getting, gaze-following) with age.
• Slight motor impairment in older chimpanzees, with reduced improvement on a simple motor task.
• Older chimpanzees showed enhanced understanding of sound-based causality.

Conclusions:

• Chimpanzee cognitive aging is complex, with domain-specific declines and some age-related advantages.
• Spatial memory and certain social cognition tasks are vulnerable to aging in chimpanzees.
• Motor skill acquisition shows subtle age-related changes.
• Hormonal status impacts spatial memory, independent of age.