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Some epistemological concerns about dissociative identity disorder and diagnostic practices in psychology

2005; Taylor & Francis; Volume: 18; Issue: 1 Linguagem: Inglês

10.1080/09515080500085338

1465-394X

Michael Shaffer, Jeffery S. Oakley,

Philosophy and History of Science

Abstract In this paper we argue that dissociative identity disorder (DID) is best interpreted as a causal model of a (possible) post-traumatic psychological process, as a mechanical model of an abnormal psychological condition. From this perspective we examine and criticize the evidential status of DID, and we demonstrate that there is really no good reason to believe that anyone has ever suffered from DID so understood. This is so because the proponents of DID violate basic methodological principles of good causal modeling. When every ounce of your concentration is fixed upon blasting a winged pig out of the sky, you do not question its species’ ontological status. James Morrow, City of Truth (1990) Acknowledgments Thanks to Hal Brown, Edward Erwin, William Bechtel, Scott Lilienfield, and an anonymous referee for helpful comments on earlier versions of this paper. Notes The dissociative disorders include dissociative amnesia, dissociative fugue, dissociative identity disorder, depersonalization disorder, and dissociative disorder not otherwise specified. Our criticisms concerning the evidential status of DID should be extendable to any disorder defined in terms of dissociation or repression. For more or less recent professional consideration of clinical treatments for DID/MPD see Braun (1993 Braun B 1993 Aids to the treatment of multiple personality disorder on a general psychiatric inpatient unit In R. Kluft, & C. Fine (Eds.) Clinical perspectives on multiple personality disorder Washington DC American Psychiatric Press [Google Scholar]), Fine (1993 Fine C 1993 A tactical integrationist perspective on the treatment of multiple personality disorder In R. Kluft, & C. Fine C. (Eds.) Clinical perspectives on multiple personality disorder Washington DC American Psychiatric Press [Google Scholar]), Kluft (1983 Kluft, R. 1983. Hypnotheraputic crisis intervention in multiple personality. American Journal of Clinical Hypnosis, 26: 73–83. [Taylor & Francis Online], [Web of Science ®] , [Google Scholar], 1993 Kluft R 1993a Clinical approaches to the integration of personalities In R. Kluft & C. Fine (Eds.) Clinical perspectives on multiple personality disorder Washington DC American Psychiatric Press [Google Scholar]a, b) Kluft R 1993b Basic principles in conducting psychotherapy of multiple personality disorder In R. Kluft & C. Fine (Eds.) Clinical perspectives on multiple personality disorder Washington DC American Psychiatric Press [Google Scholar], Loewenstein (1993 Loewenstein R 1993 Posttraumatic and dissociative aspects of transference and countertransference in the treatment of multiple personality disorder In R. Kluft & C. Fine (Eds.) Clinical perspectives on multiple personality disorder Washington DC American Psychiatric Press [Google Scholar]), Brassfield (1983 Brassfield, P. 1983. Unfolding patterns of multiple personality through hypnosis. American Journal of Clinical Hypnosis, 26: 146–152. [Taylor & Francis Online], [Web of Science ®] , [Google Scholar]), and Horevitz (1983 Horevitz, R. 1983. Hypnosis for multiple personality disorder: A framework for a beginning. American Journal of Clinical Hypnosis, 26: 138–145. [Taylor & Francis Online], [Web of Science ®] , [Google Scholar]). It is interesting to note that DID is the new name for multiple personality disorder (MPD) introduced in DSM-IV. The controversy over the status of MPD as specified in DSM-III led to some minor emendations in DSM-IV, including renaming. But, for the purposes of this paper, they are indistinguishable. See Grünbaum (1984 Grünbaum A 1984 The foundations of psychoanalysis: A philosophical critique Berkeley CA University of California Press [Google Scholar], 1993 Grünbaum A 1993 Validation in the clinical theory of psychoanalysis: a study in the philosophy of psychoanalysis Madison CT International University Press, Inc [Google Scholar]), Erwin (1996 Erwin E 1996 A final accounting: Philosophical and empirical issues in empirical psychology Cambridge MA M.I.T. Press [Google Scholar]) and Crews (1995 Crews F 1995 The memory wars: Freud's legacy in dispute New York New York Review of Books [Google Scholar]). See Ross (1997 Ross C 1997 Dissociative identity disorder: Diagnosis, clinical features and treatment of multiple personality New York John Wiley and Sons [Google Scholar]) (especially p. 31) and Hacking (1995 Hacking I 1995 Rewriting the soul Princeton NJ Princeton University Press [Crossref] , [Google Scholar]) for historical perspectives on Freud's attitude toward dissociation and how it both differs from and is similar to repression. We do not intend to suggest here that dissociation is Freudian in origin, only that it bears some resemblance to Freudian repression. Given this resemblance, the current, highly critical, attitude towards Freudian psychology also suggests that the practices and theoretical assumptions of the proponents of dissociation should be scrutinized along similar lines. Elizabeth Loftus is perhaps the most well known critic of the mechanisms of memory repression and memory recovery. Loftus has labored to show that people do not store complete records of events in their minds to which they later have access. Loftus' work on memory and suggestion tends to support the view that many of the ‘repressed’ or ‘dissociated’ memories are iatrogenic in origin. See, for example, Loftus (1980 Loftus E 1980a Memory Reading MA Addison-Wesley [Google Scholar]a, 1992 Loftus, E. 1992. When a lie becomes memory's truth: memory distortion after exposure to misinformation. Current Directions in Psychological Science, 1: 120–123. [Crossref] , [Google Scholar], 1993 Loftus, E. 1993. The reality of repressed memories. American Psychologist, 35: 518–537. [Crossref] , [Google Scholar], 1994 Loftus E (1994, March) Therapeutic recollection of childhood abuse: When a memory may not be a memory The Champion 5 10 [Google Scholar]), Loftus and Ketcham (1994 Loftus E Ketcham K 1994 The myth of repressed memory New York St. Martin's Press [Google Scholar]), Loftus and Banji (1989 Loftus, E and Hoffman, H. 1989. Misinformation and memory: The creation of new memories. Journal of Experimental Psychology: General, 118: 100–104. [Crossref], [PubMed], [Web of Science ®] , [Google Scholar]), Spanos (1994 Spanos, N. 1994. Multiple identity enactments and multiple personality disorder: A sociocognitive perspective. Psychological Bulletin, 116: 143–165. [Crossref], [PubMed], [Web of Science ®] , [Google Scholar]), and Lilienfeld, Lynn, Kirsch, Chaves, Sarbin, Ganaway and Powell (1999 Lilienfeld, S, Lynn, S, Kirsch, I, Chaves, J, Sarbin, T, Ganaway, G and Powell, R. 1999. Dissociative identity disorder and the sociocognitive model: recalling lessons of the past. Psychological Bulletin, 125: 507–523. [Crossref], [PubMed], [Web of Science ®] , [Google Scholar]) for discussion of iatrogenesis, suggestion and recovered memories. The methodological implications of these studies will be given a more satisfactory treatment in §7. The argument presented here will most closely resemble those presented in Grünbaum (1984 Grünbaum A 1993 Validation in the clinical theory of psychoanalysis: a study in the philosophy of psychoanalysis Madison CT International University Press, Inc [Google Scholar], 1993 Grünbaum A 1993 Validation in the clinical theory of psychoanalysis: a study in the philosophy of psychoanalysis Madison CT International University Press, Inc [Google Scholar]). Disorders characterized in terms of dissociation are not, however, limited to the dissociative disorders proper. Acute stress disorder, posttraumatic stress disorder, and somatization disorder are also all characterized by dissociation. Of course, the converse of the NMP is not true. See, for example, Machamer, Darden and Craver (2000 Machamer, P, Darden, L and Craver, C. 2000. Thinking about mechanisms. Philosophy of Science, 67: 1–25. [Crossref], [Web of Science ®] , [Google Scholar]), Craver (2000), Craver and Darden (2001 Craver C Darden L 2001 Discovering mechanism in neurobiology In P. Machamer, R. Grush, & P. McLaughlin 2001 Theory and method in the neurosciences Pittsburgh PA University of Pittsburgh Press [Google Scholar]), and also Bechtel (2001 Bechtel W 2001 Cognitive neuroscience In P. Machamer, R., Grush, & P. McLaughlin (Eds.) Theory and method in the neurosciences Pittsburgh PA University of Pittsburgh Press [Google Scholar]) and Glennan (1996 Glennan, S. 1996. Mechanisms and the nature of causation. Erkenntnis, 44: 49–71. [Crossref] , [Google Scholar], 2000 Glennan, S. 2000. Rethinking mechanistic explanation. Philosophy of Science, 69: S342–S353. [Crossref] , [Google Scholar]) for related approaches. See Salmon (1984 Salmon W 1984 Scientific explanation and the causal structure of the world Princeton NJ Princeton University Press [Google Scholar]) and Machamer et al. (2000 Machamer, P, Darden, L and Craver, C. 2000. Thinking about mechanisms. Philosophy of Science, 67: 1–25. [Crossref], [Web of Science ®] , [Google Scholar]), p. 7. See Glennan (2000 Glennan, S. 2000. Rethinking mechanistic explanation. Philosophy of Science, 69: S342–S353. [Crossref] , [Google Scholar]), p. S347. See Shaffer (2000 Shaffer M 2000 Idealization and empirical testing Ph.D. dissertation, University of Miami [Google Scholar]) for a more or less complete account of partial explanation. The point is noted in Machamer et al. (2000 Machamer, P, Darden, L and Craver, C. 2000. Thinking about mechanisms. Philosophy of Science, 67: 1–25. [Crossref], [Web of Science ®] , [Google Scholar]), p. 21, and is implicit in the discussion of the adequacy of mechanical models in Darden and Craver (2001). The DID model so sketched assumes that DID is post-traumatic in origin, and this is the typical assumption that has been made by proponents of DID as a legitimate psychological disorder (Boon & Draijer, 1993 Boon S Draijer N 1993 Multiple personality disorder in the Netherlands: A study in the reliability and validity of the diagnosis Amsterdam Swets & Zeitlinger [Google Scholar], ch.s 1, 2). As we shall see, however, this is not the only possible causal model of DID. See, e.g., Spanos (1994 Spanos, N. 1994. Multiple identity enactments and multiple personality disorder: A sociocognitive perspective. Psychological Bulletin, 116: 143–165. [Crossref], [PubMed], [Web of Science ®] , [Google Scholar], 1996 Spanos N 1996 Multiple identities & false memories: A sociocognitive perspective Washington DC American Psychological Association [Crossref] , [Google Scholar]) and Lilienfeld, et al. 1999 Lilienfeld, S, Lynn, S, Kirsch, I, Chaves, J, Sarbin, T, Ganaway, G and Powell, R. 1999. Dissociative identity disorder and the sociocognitive model: recalling lessons of the past. Psychological Bulletin, 125: 507–523. [Crossref], [PubMed], [Web of Science ®] , [Google Scholar] for elaboration of the so-called sociocognitive model of DID. On this model, DID is not the result of a real trauma induced splitting of personalities, but rather is only the iatrogenic, socially conditioned, play-acting of the patient as if he or she had multiple personalities. This need not be intentional, but it is iatrogenic. In what follows, when we refer to the theoretical model of DID, we are explicitly referring to the post-traumatic model as characterized by D1-D5. In our opinion, it seems to be something of a mistake to even treat the sociocognitive model of DID as a bona fide model of DID, for the sociocognitive model denies that symptom A. of the DSM-IV characterization really ever occurs. Moreover, insofar as the sociocognitive model treats DID as largely (if not wholly) iatrogenic in origin, to treat such cases as real DID would be rather like categorizing false pregnancies as real pregnancies simply because these two phenomena are characterized by very similar symptoms. We hope that, for obvious reasons, this is methodologically inappropriate. If it turns out that all the symptoms exhibited by supposed DID patients are iatrogenic in this manner, then the patients in question are not really suffering from DID as it is typically understood. So, pace Lilienfeld et al. (1999 Lilienfeld, S, Lynn, S, Kirsch, I, Chaves, J, Sarbin, T, Ganaway, G and Powell, R. 1999. Dissociative identity disorder and the sociocognitive model: recalling lessons of the past. Psychological Bulletin, 125: 507–523. [Crossref], [PubMed], [Web of Science ®] , [Google Scholar]) we do not accept that the issue of the existence of DID is a pseudo-issue that is tangential to the debate about the etiology of DID. The question of the etiology of a disorder is, in an important sense, just the question of the existence of a disorder caused in such-and-such a manner. This distinction is closely related to that discussed in Bechtel (2001 Bechtel W 2001 Cognitive neuroscience In P. Machamer, R., Grush, & P. McLaughlin (Eds.) Theory and method in the neurosciences Pittsburgh PA University of Pittsburgh Press [Google Scholar]). We are here borrowing the term ‘candidate phenomenon’ from Humphrey and Dennett (1989 Humphrey, N and Dennett, D. 1989. Speaking for ourselves: An assessment of multiple personality disorder. Raritan, 9: 68–98. [Web of Science ®] , [Google Scholar]). See Ross (1997 Ross C 1997 Dissociative identity disorder: Diagnosis, clinical features and treatment of multiple personality New York John Wiley and Sons [Google Scholar]), ch. 2, and Lilienfeld and Lynn (2003 Lilienfeld S Lynn S 2003 Dissociative identity disorder: multiple personalities, multiple controversies In S. Lilienfeld, S. Lynn & J. Lohr (Eds.) Science and pseudoscience in clinical psychology New York The Guilford Press [Google Scholar]). See Fine and Forbes (1984) for the suggestion that psychoanalytic theories ought to be judged more like theories in somatic medicine, and see Erwin (1996 Erwin E 1996 A final accounting: Philosophical and empirical issues in empirical psychology Cambridge MA M.I.T. Press [Google Scholar]), ch. 2 for a forceful response. This point is closely related to Nancy Cartwright's conception of inference to the best cause. See Cartwright (1983 Cartwright N 1983 How the laws of physics lie Oxford England Clarendon Press [Crossref] , [Google Scholar]), p. 92. To clarify, by ‘eliminate’ we mean only that competitor hypotheses must be shown to be significantly less explanatory, or less likely. The sort of reasoning going on in such cases is similar to inference to the best explanation as described in Harman (1965 Harman, G. 1965. Inference to the best explanation. The Philosophical Review, 74: 88–95. [Crossref], [Web of Science ®] , [Google Scholar]). It might be best understood as inference to the best causal model. In such reasoning we appear to be attempting to select the best causal model with respect to the data. As such, it is not really strictly required that we falsify all alternative existential claims, only that we make it clear that one of the set of plausible existential claims associated with the competing models is more likely than its competitors. The main point is that one must at least take into account all alternative models that have existential claims with non-marginal likelihoods. This condition is designed to rule out so-called ‘only game in town’ cases. As such, epistemic support for existential claims is differential. See Erwin and Siegel (1989 Erwin, E and Siegel, H. 1989. Is confirmation differential?. British Journal for the Philosophy of Science, 40: 105–105. [Crossref], [Web of Science ®] , [Google Scholar]). Again, as suggested in fn. 21, this principle will need to be weakened somewhat. We need not require that all plausible alternative existential claims be ruled out in the sense of being falsified. But one might be tempted to insist on the strong formulation of CMP qua strict falsification of such alternatives where the issue is a matter of the bare existence of some phenomenon. We take ‘plausible existential claim’ here to mean one that has a significant likelihood. How high we fix this requirement at is a partially contextual issue. See Shaffer (2000 Shaffer M 2000 Idealization and empirical testing Ph.D. dissertation, University of Miami [Google Scholar]) for discussion and elaboration on this sort of theme. See Mayo (1996 Mayo D 1996 Error and the growth of experimental knowledge Chicago University of Chicago Press [Crossref] , [Google Scholar]) for extensive discussion of such practices. Of course, all such reasoning is nonmonotonic, and so any conclusion arrived by such a procedure is revisable. As in the case of the simpler formulation of the CMP, we must interpret unlikely here to mean of sufficiently low likelihood, and, again, we believe that this is partially a contextual matter. This, of course, is a common problem in science in general. As we have suggested above, there is little in the way of other evidence for the existential claim associated with the mechanical model of DID, and, more, specifically with the existential claim asserting the instantiation of the mechanism of dissociation. First, as a survey of the literature shows (see the references in fn. 50), there is little or no physiological evidence for DID, and there do not seem to be any tests for DID other than these sort of test batteries. All of the evidence for the existence of DID is the result either of (frankly specious) physiological tests or from the components of test batteries. If the former evidence is, in point of fact, as weak as it appears to be and conflicts with our background knowledge concerning the nature and functioning of human memory (see the references in fn. 53), then unless the test batteries provide good evidence for the existence of DID, we have no good evidence for the existence of DID. There are others as well, e.g., the Dissociative Disorders Interview Schedule (DDIS). For a detailed explanation and evaluation of the DES and SCID-D see North, Ryall, Ricci and Wetzel (1993 North C Ryall J Ricci D Wetzel R 1993 Multiple personalities, multiple disorders: psychiatric classification and media influence New York Oxford University Press [Google Scholar]) and Boon and Draijer (1993 Boon S Draijer N 1993 Multiple personality disorder in the Netherlands: A study in the reliability and validity of the diagnosis Amsterdam Swets & Zeitlinger [Google Scholar]). See, for example, Armstrong (1996 Armstrong J 1996 Psychological assessment In J. Spira & I. Yalom (Eds.) Treating dissociative identity disorder San Francisco Jossey-Bass [Google Scholar]), North et al. (1993 North C Ryall J Ricci D Wetzel R 1993 Multiple personalities, multiple disorders: psychiatric classification and media influence New York Oxford University Press [Google Scholar]), Boon and Draijer (1993 Boon S Draijer N 1993 Multiple personality disorder in the Netherlands: A study in the reliability and validity of the diagnosis Amsterdam Swets & Zeitlinger [Google Scholar]), and Putnam (1989 Putnam F 1989 Diagnosis and treatment of multiple personality disorder New York The Guilford Press [Google Scholar]). See, for example, Butcher (2002 Butcher J 2002a Clinical personality assessment: an overview In J. Butcher (Ed.) Clinical personality assessment Oxford England Oxford University Press [Google Scholar]a), Exner and Erdberg (2002 Exner J Erdberg P 2002 Why use personality tests? A brief history and some comments In J. Butcher (Ed.) Clinical personality assessment Oxford England Oxford University Press [Google Scholar]), and Acklin (2002 Ackilin M 2002 How to select personality tests for a test battery In J. Butcher (Ed.) Clinical personality assessment Oxford England Oxford University Press [Google Scholar]). See the various articles in Butcher (2002 Butcher J 2002b Clinical personality assessment Oxford England Oxford University Press [Google Scholar]b). See Graham (1990 Graham J 1990 MMPI-2: Assessing personality and psychopathology Oxford England Oxford University Press [Google Scholar]), ch. 1. The criticisms raised here are similar to those raised in, e.g., Lilienfeld et al. (1999 Lilienfeld, S, Lynn, S, Kirsch, I, Chaves, J, Sarbin, T, Ganaway, G and Powell, R. 1999. Dissociative identity disorder and the sociocognitive model: recalling lessons of the past. Psychological Bulletin, 125: 507–523. [Crossref], [PubMed], [Web of Science ®] , [Google Scholar]), Lilienfeld & Lynn (2003 Lilienfeld S Lynn S 2003 Dissociative identity disorder: multiple personalities, multiple controversies In S. Lilienfeld, S. Lynn & J. Lohr (Eds.) Science and pseudoscience in clinical psychology New York The Guilford Press [Google Scholar]), Merskey (1992 Merskey, H. 1992. The manufacture of multiple personalities: The production of multiple personality disorder. British Journal of Psychiatry, 160: 327–340. [Crossref], [PubMed], [Web of Science ®] , [Google Scholar]), and Spanos (1994 Spanos, N. 1994. Multiple identity enactments and multiple personality disorder: A sociocognitive perspective. Psychological Bulletin, 116: 143–165. [Crossref], [PubMed], [Web of Science ®] , [Google Scholar]). However, we believe that our criticisms are, nevertheless, novel in focus. For details of the MMPI and MMPI-2, see North et al. (1993 North C Ryall J Ricci D Wetzel R 1993 Multiple personalities, multiple disorders: psychiatric classification and media influence New York Oxford University Press [Google Scholar]), and, especially, Greene (1991 Greene R 1991 MMPI-2/MMPI: an interpretive manual Boston Allyn & Bacon [Google Scholar]). We employ the terms ‘reliable’ in the sense of epistemological reliabilism, whereby a method is reliable, if and only if, it tends to produce true beliefs rather than false beliefs. The criticisms we raise in this section are not entirely new as, for example, reading of Graham (1990 Graham J 1990 MMPI-2: Assessing personality and psychopathology Oxford England Oxford University Press [Google Scholar]), Levitt (1989 Levitt E 1989 The clinical application of the MMPI special scales Hillsdale NJ Lawrence Erlbaum Publishers [Google Scholar]), and Levitt and Gotts (1995 Levitt E Gotts E 1995 The clinical application of the MMPI special scales (2nd ed.) Hillsdale NJ Lawrence Erlbaum Publishers [Google Scholar]) illustrates. However, despite general criticism of the MMPI and MMPI-2 as truly reliable diagnostic instruments in the sense intended by its authors, Starke Hathaway and J. C. McKinley, it has nevertheless continued to be employed with startling frequency in psychodiagnostic test batteries. This is made especially clear in the case of DID, for example, in North et al. (1993 North C Ryall J Ricci D Wetzel R 1993 Multiple personalities, multiple disorders: psychiatric classification and media influence New York Oxford University Press [Google Scholar]), ch. 4, Putnam (1989 Putnam F 1989 Diagnosis and treatment of multiple personality disorder New York The Guilford Press [Google Scholar]), ch. 4, Ross (1997 Ross C 1997 Dissociative identity disorder: Diagnosis, clinical features and treatment of multiple personality New York John Wiley and Sons [Google Scholar]), ch. 7, and Armstrong (1996 Armstrong J 1996 Psychological assessment In J. Spira & I. Yalom (Eds.) Treating dissociative identity disorder San Francisco Jossey-Bass [Google Scholar]). See Greene (1991 Greene R 1991 MMPI-2/MMPI: an interpretive manual Boston Allyn & Bacon [Google Scholar]), ch. 1, Graham (1990 Graham J 1990 MMPI-2: Assessing personality and psychopathology Oxford England Oxford University Press [Google Scholar]), and Colligan et al. (1983 Colligan R Osborne D Swenson W Offord K 1983 The MMPI: A contemporary normative study New York Praeger [Google Scholar]) for historical accounts of the MMPI, the MMPI-2 and the rationale behind their construction. This is especially troubling in the case of psychological phenomena that may not, in principle, be publicly observable. It is interesting to note that this seems to be one of the reasons behind the construction of the DES and the SCID-D, and these instruments were supposed to provide for more reliable differential diagnosis of DID and other dissociative disorders. But, we shall see that these instruments suffer from related, but somewhat different methodological flaws. See Bernstein and Putnam (1986 Bernstein, E and Putnam, F. 1986. Development, reliability and validity of a dissociation scale. The Journal of Nervous and Mental Disease, 174: 727–735. [Crossref], [PubMed], [Web of Science ®] , [Google Scholar]), p. 729. See Carlson et al. (1993). See Boon and Draijer (1993 Boon S Draijer N 1993 Multiple personality disorder in the Netherlands: A study in the reliability and validity of the diagnosis Amsterdam Swets & Zeitlinger [Google Scholar]). In spite of the caveats issued concerning the inability of the DES to ground differential diagnoses, Ross, for example, still claims that, ‘… it is the best self-report instrument for measuring dissociation available (1990), p. 173)’. This is the method of validation adopted by Bernstein and Putnam (1986 Bernstein, E and Putnam, F. 1986. Development, reliability and validity of a dissociation scale. The Journal of Nervous and Mental Disease, 174: 727–735. [Crossref], [PubMed], [Web of Science ®] , [Google Scholar]). See Boon and Draijer (1993 Boon S Draijer N 1993 Multiple personality disorder in the Netherlands: A study in the reliability and validity of the diagnosis Amsterdam Swets & Zeitlinger [Google Scholar]) for extensive discussion of this attempt to validate the DES. For examples of SCID-D questions and structures, see Steinberg et al. (1990 Steinberg, M, Rounsaville, B and Cicchetti, D. 1990. The structured clinical interview for DSM-III-R dissociative disorders: preliminary report on a new diagnostic instrument. American Journal of Psychiatry, 147: 76–82. [Crossref], [PubMed], [Web of Science ®] , [Google Scholar]). See Merskey (1992 Merskey, H. 1992. The manufacture of multiple personalities: The production of multiple personality disorder. British Journal of Psychiatry, 160: 327–340. [Crossref], [PubMed], [Web of Science ®] , [Google Scholar]), Piper (1997 Piper A 1997 Hoax and reality: The bizarre world of multiple personality disorder Northvale NJ Jason Aronson Publishing [Google Scholar]), Spanos (1994 Spanos, N. 1994. Multiple identity enactments and multiple personality disorder: A sociocognitive perspective. Psychological Bulletin, 116: 143–165. [Crossref], [PubMed], [Web of Science ®] , [Google Scholar], 1996 Spanos N 1996 Multiple identities & false memories: A sociocognitive perspective Washington DC American Psychological Association [Crossref] , [Google Scholar]), Lilienfeld et al. (1999 Lilienfeld, S, Lynn, S, Kirsch, I, Chaves, J, Sarbin, T, Ganaway, G and Powell, R. 1999. Dissociative identity disorder and the sociocognitive model: recalling lessons of the past. Psychological Bulletin, 125: 507–523. [Crossref], [PubMed], [Web of Science ®] , [Google Scholar]), and Lilienfeld and Lynn (2003 Lilienfeld S Lynn S 2003 Dissociative identity disorder: multiple personalities, multiple controversies In S. Lilienfeld, S. Lynn & J. Lohr (Eds.) Science and pseudoscience in clinical psychology New York The Guilford Press [Google Scholar]) for defense of the view that DID is not post-traumatic in origin, but rather is likely iatrogenic in origin. An examination of the relevant literature on the physiological aspects of dissociation shows that there is some anecdotal evidence concerning the physiological basis of dissociation, as well as a strained effort to mount a kind of parity argument between the phenomenon of hypnosis and the phenomenon of dissociation. But, as demonstrated in §4 there is no real deep mechanical understanding of how dissociation is supposed to work. Consideration of the physiological basis of dissociation is addressed in Ludwig (1983 Ludwig, A. 1983. The psychological functions of dissociation. American Journal of Clinical Hypnosis, 26: 93–99. [Taylor & Francis Online], [Web of Science ®] , [Google Scholar]), Miller and Triggiano (1992 Miller, S and Triggiano, P. 1992. The psychophysiological investigation of multiple personality disorder: Review and update. American Journal of Clinical Hypnosis, 35: 47–61. [Taylor & Francis Online], [Web of Science ®] , [Google Scholar]), Braun (1983 Braun, B. 1983a. 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Many memories retrieved with hypnosis are accurate. American Journal of Clinical Hypnosis, 36: 174–176. [Google Scholar]), Loftus et al. (1994 Loftus, E, Garry, M, Brown, S and Rader, M. 1994. Near-natal memories, past-life memories, and other memory myths. American Journal of Clinical Hypnosis, 36: 176–179. [Web of Science ®] , [Google Scholar]), Lynn et al. (1994 Lynn, S, Meyers, B and Sivic, H. 1994. Psychotherapists’ beliefs, repressed memories of abuse, and hypnosis: What have we really learned?. American Journal of Clinical Hypnosis, 35: 182–182. [Google Scholar]), and ch. 6 of Aldridge-Morris (1989 Aldridge-Morris R 1989 Multiple personality: an exercise in deception Hillsdale NJ Lawrence Erlbaum Associates [Google Scholar]). One alternative possibility for improving the situation might be to appeal to the bootstrapping methods as understood in Cronbach and Meehl (1955 Cronbach, L and Meehl, P. 1955. Construct validity in psychological tests. Psychological Bulletin, 52: 281–302. [Crossref], [PubMed], [Web of Science ®] , [Google Scholar]) in order to improve the reliability of the instruments we have discussed. Via bootstrapping we are supposed to be able to develop tests with greater validity than the criterion on the basis of which it was originally developed. For example, our primitive test for heat by the use of our tactile senses is not very reliable, and has been replaced by far more sophisticated and reliable operational methods for determining temperature, i.e. thermometers, that correlate (roughly) with human temperature sense. So, initially fallible criterion can be replaced by conceptual enrichment/change and lead to the development of much more reliable instruments that test for the property in question. In effect, one pulls one's self up by the bootstraps. While this suggestion is perhaps useful here, it, of course, depends on the development of those more highly enriched tests and our showing that they correlate with our prior, less reliable, tests for that property. However, bootstrapping can only occur if the original property that one is trying to develop an improved criterion for actually exists. Absent any independent reasons to suspect that the original test for the criterion is at least partially reliable, there is no purchase for such bootstrapping. Such bootstrapping in no way provides the kind of evidence needed to make existential claims of the sort with which we are concerned. Of course, the inclusion of memory repression in this theory is a Freudian influence. In other words, memory is taken to be a reliable source of beliefs about the past. Representative literature on the topic includes Loftus (1980 Loftus E 1980a Memory Reading MA Addison-Wesley [Google Scholar]a, 1992 Loftus, E. 1992. 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