ABSTRACT
A battery of cognitive and sensory-motor tests was given to a large number of French railway operatives ranging in age from the 20s to the 50s, and to trainees in their teenage years. The adults were divided into 5-year age ranges each of which was further divided into two levels of attainment in primary education. Declines of performance with age from the early 20s onwards occurred in all tests. It was most marked for tasks requiring complex muscle coordination or secondary memory, and least for digit span and sensory-motor tasks requiring simple responses. Educational attainment showed to greater advantage in the cognitive than in the sensory-motor tests. A factor analysis indicated that, with few exceptions, the factor structure remained constant throughout the adult age ranges and at both educational levels. Performance by the trainees was less in some tests and greater in others than that of adults in their 20s. The data provide a unique factual contribution to knowledge of age changes during the middle years.
