A CASE-STUDY OF A STRONG PERCEPTUAL DEFICIT WITHOUT AGNOSIA - EVIDENCE AGAINST SEQUENTIAL PERCEPTION AND MEMORY

This paper reports the case of P.G., a patient who is not agnosic desp ite massive failure in low level visual perceptual processing tests de aling with spatial or shape information. P.G.'s preserved abilities to identify objects is difficult to be accounted for in the framework of standard models of visual identification which presume that construct ion of a structural code by perception is necessary in order to access memory. Our data argues against this hypothesis of sequential process ing of perception and memory, and indicates that knowledge influences our way of ''seeing'' from the first stages of the so called perceptua l processing.