Spiral aftereffect in assessment of brain damage

The potential role of the Archimedes spiral aftereffect, an illusory negative aftereffect of apparent movement, in the assessment of brain damage has been the subject of investigation by clinicians for over thirty years. The results bearing on its utility have been highly equivocal. This paper reviews the more important studies, identifies salient issues, and suggests directions for research into brain damage using this intriguing procedure.