Imagery and Recognition: Dissociable Measures of Memory?

Abstract

An assumption of many theories of visual cognition is that imagery tasks and picture recognition tasks tap the same kind of memory processes (i.e. visual), implying that these two types of tests can be used as interchangeable measures of visual memory. In this paper, we investigated whether articulatory suppression—a variable known to improve imagery performance—has a similar effect on picture recognition performance. In Experiment 1, subjects performed either an imagery task or a recognition task while engaging or not in articulatory suppression; in Experiment 2, the same subjects performed first the imagery task, and then the recognition task, while engaging or not in articulatory suppression. When the type of task was manipulated between subjects (Experiment 1), imagery performance was significantly improved by articulatory suppression. In contrast, recognition performance was significantly impaired by the introduction of articulatory suppression. In accordance with results of Experiment 1, in Experiment 2 imagery and recognition performance were found to be unrelated. However, when the same subjects performed both tasks, the opposite effect of articulatory suppression on imagery vs recognition performance was observed only on the first item. It does appear that when the imagery task and the picture recognition task are performed in isolation, performance is found to be independent, suggesting that the two tasks are mediated by different mechanisms. However, when a within-subjects design is used, performance in one task can be contaminated by the presence of the other task.