Aging in the rhesus monkey: effects on visual discrimination learning and reversal learning

J Gerontol. 1979 Mar;34(2):209-19. doi: 10.1093/geronj/34.2.209.

Abstract

The behavior of aged rhesus monkeys (18 years and older) was compared to that of young monkeys (3 to 6 years old) to evaluate their relative abilities to learn a series of visual discrimination and discrimination reversal problems. Using a subject-paced, automated experimental procedure designed to optimize stimulus control and facilitate execution of choice responses, no consistent age-related differences were observed in the ability to learn new color and pattern discrimination problems of varying difficulty. However, a severe and consistent deficity on reversal learning did occur. A detailed analysis of this deficit revealed that not only did the aged monkeys take longer to extinguish the old habit and return to chance performance, but they continued to display a deficit in establishing accurate performance at above-chance levels as well. Since no reliable age differences were observed on the original discrimination learning problems, these data suggest that aging impairs mechanisms involved with response rigidity and/or susceptibility to intertrial proactive interference, more severely than those involved with the simple formation of new associations.

MeSH terms

  • Aging*
  • Animals
  • Color Perception
  • Discrimination Learning*
  • Female
  • Haplorhini
  • Macaca mulatta
  • Male
  • Reversal Learning*
  • Visual Perception*