Both Freud and Rogers talk of denial as a mechanism to delay or prevent potentially threatening aspects of the environment from reaching conscious awareness. Subjects' GSR were also recorded. Words were flashed initially at 10 msec. Increments until subjects correctly identified the word. The pattern of errors also differed for the two word groups.
Emotional reactivity is an accompaniment of perceptual defense.
Certain features of the object, which the subject does not consciously perceive, are nevertheless physically affecting the body. McGinnies argued against these artifacts in favor of his conclusions. But other research, notably that of Howes and Solomon, suggests that concerns about the artifacts are reasonable.