“…In response, many -about 50% -of hypnotizable subjects give 'covert' pain reports comparable to those collected under normal waking conditions (Knox, Morgan and Hilgard, 1974;Hilgard, Morgan and Macdonald, 1975;Hilgard, Hilgard, Macdonald, Morgan and Johnson, 1978). For Hilgard, the hidden observer was only one example of dissociation in hypnosis: the stimulus is represented in the cognitive system, but in a manner not normally accessible to phenomenal awareness (Kihlstrom, 1984(Kihlstrom, , 1992(Kihlstrom, , 1998(Kihlstrom, , 2005a. Although Hilgard's observations of covert pain reports in analgesia have been repeated by other investigators and have been extended to deafness, dreams, anosmia and negative hallucination (Spanos and Hewitt, 1980;Laurence and Perry, 1981;Nogrady, McConkey, Laurence and Perry, 1983;Spanos, Gwynn and Stam, 1983;Zamansky and Bartis, 1985;Mare, Lynn, Kvaal, Segal and Sivec, 1994), interpretation of the phenomenon has been more controversial.…”