The capacity for selective concentration on color versus form of consonants

The concept of active exclusion or inhibition of some stimuli while focusing on others has been largely ignored or rejected in recent work in the field of attention. As part of an ongoing series of studies involving five posthypnotically cued levels of mental concentration, it was possible to test the capacity for active blurring of one stimulus attribute (form) while simultaneously perceiving another attribute (color) accurately. In lowered concentration conditions three highly trained hypnotic Ss were dramatically successful in blurring the form and thereby impairing identification of colored consonants flashed tachistoscopically at speeds ranging from 300 msec down to 50 msec—without any concomitant loss in accuracy of identification of the color in which the letter was printed. Among a supplemental series of control experiments, it was further demonstrated that the active inhibitory process can be reversed so as to act upon color but not form; and that the Ss were unable to duplicate these feats in the waking state without benefit of posthypnotic programming. A theoretical interpretation of the findings, in terms of a conceptual model of the mind, is offered.