Differences in memory retrieval: a construct validity investigation.

Long-term memory retrieval efficiency was investigated as a potential underlying source of individual and developmental differences in cognitive functioning. Fourth-grade, eighth-grade, and college-aged subjects participated in a task using the Posner letter-matching paradigm. Letter pairs were presented simultaneously under physical-match and name-match instruction conditions. Reaction times were used to estimate parameters of long-term memory retrieval efficiency, basic encoding, decision, and response time, and name and physical output interference. Psychometric tests of verbal and spatial ability were included to assess convergent and discriminant validity of hypothesized relationships between aptitude test performance and basic cognitive processes. Developmental differences were observed in most but not all of the processing variables. Individual difference analyses indicated that less confounded estimates of processing parameters were not systematically related to verbal ability at any age level. Basic encoding and response speed was the most consistent correlate of spatial ability. The results suggest difficulties in previous interpretations of NIPI-verbal ability relationships. The study of cognitive processes in interaction and embedded in meaningful tasks is discussed.