Processing time, imagery, and spatial memory.

Measures of cognitive processing time, imagery skill, and spatial memory span were administered to 128 8- to 20-year-olds. Age correlated positively with spatial memory span and accuracy on the imagery tasks but negatively with times on the cognitive processing and imagery tasks. Results of path analyses and structural-equation modeling were consistent with a causal model in which age-related change in speed of processing is associated with more effective imagery. In turn, imagery is associated with spatial memory span. Age was also associated with imagery and spatial span, indicating that other age-related variables need to be incorporated into the causal model.