“…A performance differentiai between normals and chronic psychotics during response acquisition has also been reported by Mednick and The lower operant emission behaviour o.f the chronic psychotics has been reported (Lindsley, 1956b, p. 152) to correl.ate significantly (p <.01) with severity of ward behaviour when using the L-M FergusFalls sca1e (Lucero and Meyer, 1951 The suggestion of a linear relationship between these two variables (severity of behaviour disorder and operant rate) with chronic psychotics has been confirmed by King, Armitage and Tilton (1960).…”