The Status of Several Conservation Abilities Across the Life-Span

Subjects ranging in age from 6 to over 65 years were tested on standard conservation of number, substance, weight, and volume measures. Although the ability to conserve number held up well with age, quantity conservation performance was generally lower in the subjects over 65 years of age than in the college and adult age groups. Such deficits in conservation performance are hypothesized to be reflections of the neurological decrement inherent in the aging process.