  In fact, the distinction between these two types of error, cognitive error and sensory misrepresentation, is not completely clear-cut in Descartes.  In the case of the amputee, the pain seems to be in fingers that are not there. That appears to be a clear case of sensory misrepresentation: the representational content (that the fingers are damaged) does not match the world. Similarly with the partially submerged stick. It may look bent. In these cases, even if we use our  intellects to interpret the illusions or sensory misrepresentations so as to avoid error by withholding judgment or even by judging correctly (7:438),  there is a clear sense in which sensory misrepresentation has occurred.