Is an Object an Object an Object? Cognitive and Neuropsychological Investigations of Domain Specificity in Visual Object Recognition

Are all types of objects recog nized in the same way, or are differ ent kinds of visual object recognition systems used to recognize different types of objects? Most current work on object recognition in cognitive science has assumed, explicitly or implicitly, that all visual stimuli are recognized by a common set of mechanisms. Cognitive scientists such as Marr1 and Biederman,2 who have proposed comprehensive theo ries of object recognition, do not specify different types of representa tions or processes for different types of stimuli. Rather, these scientists have described a single type of sys tem capable of recognizing as wide a range of stimuli as possible. Other researchers have ques tioned the existence of a general purpose pattern recognition system, and have instead suggested that the visual system has evolved numerous specialized subsystems for recogniz ing different types of stimuli. Proba bly the most extreme proponent of this view was Konorski,3 who sug gested that there were nine different subsystems used in visual recogni