Freud Was Wrong, Installment MCMXII

Pope and his colleagues reviewed 63 studies of documented trauma victims, including more than 10,000 subjects, and failed to find even a single convincing case of amnesia for the traumatic event that could not be explained by organic factors, infantile and childhood amnesia, ordinary forgetting, or other normal memory processes (Pope et al 1998, Pope et al 2000). Most trauma victims remember their experiences all too vividly – an empirical fact that is consistent with what is known from the laboratory about arousal and memory (Cahill & McGaugh 1998). Whatever forgetting occurs appears not to be the product of psychological defenses such as repression or dissociation.

On the other hand, Brown and his colleagues have argued that at least nine of the studies cited by Pope and his colleagues do, in fact, offer evidence for traumatic amnesia (see also Brown et al 1998, Brown et al 1999). However, re-examination of the evidence supports Pope’s initial conclusions (Piper et al 2000). For example, two individuals who were amnesic for a lightning strike were "side-flash" victims who received the equivalent of electroconvulsive shock; some of the children who were amnesic for a flood disaster were as young as two years old at the time of the incident; and while approximately one-third of older children who were earthquake survivors were reported as showing psychogenic amnesia for the event, more than two-thirds of a control group of children who were not exposed to the trauma met the same criterion. One study did report a high rate of dissociative symptoms, as measured by the DES, among those who experienced the Loma Prieta earthquake of 1989 (Cardena & Spiegel 1993), but these were most likely common experiences of depersonalization and derealization; there was no evidence that any subject forgot the earthquake.

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