Effect of pair-housing on operant behavior task performance by rhesus monkeys

Area of Science:

• Primate behavior
• Animal cognition
• Neuroscience research

Background:

• Operant behavior testing in rhesus macaques is a model for complex brain functions.
• Understanding the impact of housing conditions on behavior is crucial for experimental design.

Purpose of the Study:

• To evaluate the effects of pair-housing on operant behaviors in rhesus macaques.
• To assess how social housing influences motivation, memory, attention, discrimination, and learning tasks.

Main Methods:

• Sixteen young, male rhesus monkeys were assessed on progressive ratio (PR), delayed matching-to-sample (DMTS), conditioned position responding (CPR), and incremental repeated acquisition (IRA) tasks.
• Eight monkeys were pair-housed (20h/day access) while eight controls remained individually housed.
• Behavioral performance was compared before, during, and after the transition to pair-housing.

Main Results:

• Conditioned position responding (CPR) and incremental repeated acquisition (IRA) task performance remained unchanged by housing condition.
• Controls showed increased trials completed on progressive ratio (PR) and delayed matching-to-sample (DMTS) tasks, unlike pair-housed monkeys.
• Pair-housing did not significantly alter performance on all tested operant behaviors.

Conclusions:

• Pair-housing rhesus macaques is a viable option for operant behavior studies.
• Housing conditions can influence specific behavioral parameters, particularly motivation and memory tasks.
• Researchers must consider housing effects during experimental design for primate behavior studies.