The role of the central executive in the storage of visually-constructed images

The present study examines whether the storage of a visually-constructed image requires executive resources. Experiment 1 was conducted to determine how long a visually-constructed pattern (imaging task) could be stored without sufficient rehearsal at 1 s, 6 s, and 11 s intervals. The results indicate that memory performance was significantly disrupted at the 11 s interval. Using this interval, memory performances for the imaging task and a perceptual task (requiring the temporary storage of a perceived pattern) were compared in Experiment 2. The two memory tasks were matched in terms of their degree of difficulty. During the interval, participants performed either an articulatory suppression task that interferes with the maintenance of verbally-coded materials or a random number generation (RNG) task that interferes with executive resources. The results indicate that performance for the imaging task, compared to the perceptual task, was severely disrupted by the RNG task, while performance of both memory tasks was not disrupted by the suppression task. This suggests that maintenance of a visually-constructed image, which does not involve verbal processing, is a function that requires executive resources.