ABSTRACT
Stimulus localisation, perception of line orientation, and depth perception are different aspects of visuospatial perception that can be selectively impaired after brain lesions. In agreement with the claim that mental images activate the same representations involved in visuospatial processing, most patients with selective disturbances of visual perception manifest corresponding impairments in mental imagery. Neuropsychological analysis discriminates between spatial perception, spatial memory, and visuo-motor coordination disorders. Neuropsychological data on patients, as well as the results of neuroimaging studies in normal subjects, have been very informative in trying to solve the debate about the format of mental images. Several neuroimaging studies have provided further and stronger evidence that visual imagery activates occipital cortex in normal subjects performing visual imagery tasks. Neuropsychological studies have provided convincing evidence that the ability to transform mental images is distinct from the ability to generate them.
