ABSTRACT
This chapter presents evidence suggesting that Type P and Type N part-whole relationships can be separated, and that they produce independent effects in tasks requiring responses to the structural identity of local stimulus features. The performance of the patient was examined on three tasks, in the first two, responses had to be made to the structural identity of local parts of stimuli. In the third, responses could be made using local position information. The contrast between the patient's performance on these tasks suggests that Type P and Type N part-whole relationships have separate functional roles in object perception. Examination of H. J. A's object recognition indicated that his ability to identify objects correctly was dependent on the identification of salient local features, suggesting that he could pick up local feature descriptions. In particular, he had severe difficulties in visually recognizing real common objects, photographs, and line drawings, he also had achromotopsia.
