Visual Agnosia – An Update on Disorders of Visual Recognition Emmie Russell Prize 1992

R.Cingiloglu, BA(Hons)(Macq), DipAppSc(Cumb), DOBA

Normally, we can recognise objects around us at a glance. However, selective brain damage can cause visual agnosia. Patients with this disorder are unable to recognise familiar objects, despite normal visual acuity. Although they can see well enough to accurately describe parts of the object, they cannot recognise what the object is or what it may be used for. What is more puzzling is that, when patients are allowed to hold the object or hear its characteristic sound, they can often identify it immediately. The study of this disorder has led to considerable progress in our understanding of the various ways visual processing can break down. A review is presented of the different types of visual agnosia which can occur, and implications for normal visual object recognition.