“…What can be said of this method? A number of writers have already addressed such difficulties as, for example, the lack of a fixation point in the blank field (Fudin, 1986; Porterfield & Golding, 1985); inattention to the visual angle subtended by the stimulus and the degree to which a syntactically complex stimulus can be processed subliminally (Fudin, 1986; Spence, Klein, & Fernandez, 1984); the need for control stimuli to be more psychologically neutral and structurally similar to the experimental stimuli (Condon & Allen, 1980; Fudin, 1986; Porterfield & Golding, 1985); and statistical problems created by using change scores (Porterfield & Golding, 1985). Finally, Silverman himself drew attention to the problem of uncontrolled illumination levels in the tachistoscopic fields when he discovered that this factor had contributed to the variable results in a set of experiments (Silverman, Ross, Adler, & Lustig, 1978).…”