Spatial orienting of attention in adult and aged rhesus monkeys.

Aging produces changes in a variety of neural systems that result in a distinct neuropsychological profile of cognitive deficits. To determine the extent of functional decline in cognition with aging, the authors assessed attentional ability in adult (10-15 years old) and aged (28-33 years old) rhesus monkeys (Macaca mulatta) in 3 experiments, using a paradigm adapted from M. I. Posner, J. A. Walker, F. J. Friedrich, and R. D. Rafal (1984), in which a peripheral cue indicates the probable location of a target. Orienting of attention was not disrupted in aged monkeys. Response times of aged monkeys were comparable with adult monkeys' both in the attention task and in a simple reaction time task. These results suggest that the neural systems that subserve spatial orienting of attention remain intact in aged nonhuman primates.