The laterality of mental image generation: a test with normal subjects

Recent evidence supporting the hypothesis that mental image generation is lateralized to the left hemisphere is summarized, and a new test of this hypothesis, using a tachistoscopic, lateralized visual discrimination task with normal subjects, is presented. When mental images of the stimuli were used as templates to facilitate the visual discrimination, the effect of imagery was greater for the right visual field (left hemisphere) stimulus presentations. This result is discussed in relation to earlier findings on the hemisphericity of imagery and of visual expectancy.