Relative scotoma and statokinetic dissociation (Riddoch's phenomenon) from occipital lobe dysfunction.

Riddoch's phenomenon, in which a stimulus is perceived during movement but not with static presentation, has been reported for occipital lobe and anterior visual pathway disorders. To our knowledge, a threshold for movement detection in the affected hemifield has not been reported. A case of statokinetic dissociation from occipital lobe infarction is presented in which a threshold range for movement detection was identified. The possible role of separate channels in the visual cortex for analysis of kinetic and static stimuli is suggested.