Approximately 100 years ago, Bleuler famously declared that “Sensory response to external stimulus is quite normal” in schizophrenia, followed however by the cryptic statement: “Busch and Kraepelin have found in perception experiment (using the shutter and revolving drum apparatus) that schizophrenics show many more errors and particularly omissions than do the healthy … Using accurate apparatus, we were unable to substantiate these findings”.