Although roles have been proposed for both graphomotor
speed and learning in the execution of Digit Symbol, few
data have been available concerning performance across
the adult lifespan on the Symbol Copy, paired associates,
or free recall measures derived from Digit Symbol and recommended
in the WAIS–R–NI. We report findings on 177
healthy older adults (ages 50–90), providing normative
data by age group, education level, and gender. As previously
reported, Digit Symbol scores decline steeply with age
(r = −.64). Symbol Copy speed declines almost
as steeply (r = −.58). Incidental learning,
however, declines only modestly (r = −.26
on both measures). Symbol Copy is a far stronger correlate
of Digit Symbol (r = .72) than are paired associates
or free recall (r = .26 and r = .28,
respectively). The 2 incidental learning measures do, however,
offer valuable supplementary information as part of a comprehensive
individual assessment. When low Digit Symbol scores are
produced by slowing on Symbol Copy, further evaluation
of perceptual and motor speed and dexterity are indicated.
When low incidental learning scores are obtained, further
evaluation of memory is warranted. Qualitative analysis
of errors (e.g., rotations) made on the incidental learning
procedures may also be valuable. (JINS, 2000,
6, 770–780.)
Persistence of the spacing effect in free recall under varying incidental learning conditions
