[2] Riddoch's description was dismissed by Sir Gordon Holmes in a 1918 paper[3] in which he wrote that "The condition described by Riddoch should not be spoken of as a dissociation of the elements of visual sensation" because "occipital lesions do not produce true dissociations of function with intact retinal sensibility".
[5][6] With that new knowledge, a new study of patient GY, who had been used extensively to demonstrate the phenomenon of blindsight (that is to say the ability to discriminate correctly visual stimuli presented to the blind field without conscious awareness) led to interesting findings.
The re-examination showed that, when presented with fast-moving, high contrast, visual stimuli in his blind field, he could discriminate their presence and direction of motion consciously,[7][1] This, in turn, led to a re-classification of blindsight into Type 1 and Type 2[8] the former adhering to the previous definition of blindsight while the latter acknowledging the fact that the experience of such subjects can be conscious even if much degraded.
The subject may only have awareness of the movement without visual perception of it (gnosanopsia),[1] or the general shape of a moving object may be perceivable as a shadow-like outline.
[9] The syndrome is named after George Riddoch who had been a temporary officer in the Royal Army Medical Corps and examined soldiers who were blinded by gunshot wounds to their brains.