A COMPARISON OF CHILDRENS PERFORMANCE ON 2 RECOGNITION MEMORY TASKS -DELAYED NONMATCH-TO-SAMPLE VERSUS VISUAL PAIRED-COMPARISON

Although 4- to 6-month-old children have a significant tendency to loo k at new stimuli in a visual paired-comparison task (VPC), they have d ifficulty in consistently choosing novel objects in a delayed nonmatch -to-sample task (DNMS). To evaluate which factors could account for th is difficulty, we tested human infants (10-107 months) and adults (17- 25 years) in a DNMS task while monitoring eye fixations. The results i ndicated that children at all ages reliably looked at (VPC scores) or chose (DNMS scores) the new stimuli about 60% of the time, indicating that both tasks measure visual recognition memory. A videotape analysi s of visual attention revealed that children younger than 22 months, b ut not older children, spent significantly more time visually explorin g the objects rather than looking at the food reward under it. Althoug h this visual attraction to objects in children younger than 22 months of age may have impaired the formation of stimulus-reinforcer associa tion needed to solve the DNMS task, this was not the case for older ch ildren, since beyond 22 months of age children consistently looked at the reward while displacing the objects. These results suggest that ot her cognitive abilities required by the DNMS task may not be fully fun ctional even in children 22 months and older. (C) 1993 John Wiley & So ns, Inc.