Specificity of Autobiographical Memory

The growing body of literature on the specificity of autobiographical recall is important to the study of trauma and autobiographical memory functioning. As mentioned earlier, "overgeneral" autobiographical memory, first reported by Williams and Broadbent (1986), refers to autobiographical memory reports that are categorical in nature and lacking in detail and vividness. Such overgeneral autobiographical memory has been found in individuals with a wide range of psychological disorders (e.g., major depression, PTSD, obsessive-compulsive disorder, acute stress disorder; Rubin, Feldman, & Beckham, 2004; Wessel, Merckelbach, & Dekkers, 2002). The opposite of overgeneral memory is memory specificity.

Investigations of autobiographical memory specificity have been conducted with adolescents and adults who experienced a traumatic event during childhood. Evidence for Williams' (1996) proposal that the experience of adverse events during childhood may disrupt the normal development of autobiographical memory specificity, causing children to maintain a categoric retrieval style that is typical for early memory functioning, was first reported by Kuyken and Brewin (1995). Depressed female patients with a history of child sexual abuse retrieved less specific memories to positive and negative cue words compared to depressed patients without abuse histories. A similar pattern of results was later reported by Henderson, Hargreaves, Gregory, and Williams (2002) with female adult victims of child sexual abuse.

However, failures to replicate significant relations between trauma and overgeneral memory also exist (Arntz, Meeren, & Wessel, 2002; Hermans et al., 2004; Kuyken et al., 2006; Orbach, Lamb, Sternberg, Williams, & Dawud-Noursi, 2001; Wessel, Meeren, Peeters, Arntz, & Merckelbach, 2001; Wilhelm, McNally, Baer, & Florin, 1997). Moreover, some studies have reported more specific memory for individuals with maltreatment histories and/or greater psychopathology symptoms. Regarding adults, for example, Peeters, Wessel, Merckelbach, and Boon-Vermeeren (2002) found that childhood trauma predicted greater memory specificity in response to negative cue words. Burnside, Startup, Byatt, Rollinson, and Hill (2004) reported that abused adult women with depression reported fewer overgeneral memories to negative cue words compared to abused women with no self-reported depression symptomology. Similarly, Hermans et al. (2004) examined the relation between autobiographical memory specificity and self-reported trauma in depressed adults. Although physical abuse was significantly associated with poor memory specificity, sexual abuse was not. In addition, a positive relation was found between frequency of memory intrusions and autobiographical memory specificity.

Research with adolescents has revealed similarly mixed patterns. Swales, Williams, and Wood (2001) examined autobiographical memory performance of inpatient adolescents with a mix of diagnoses to normative data from a school sample. Overall, the clinical group produced less specific memories than the control group. However, within the clinical group, a positive relation existed between autobiographical memory specificity, depression, and hopelessness. In Orbach et al.'s (2001) study of adolescents with childhood exposure to family violence, neither witnessing domestic violence nor being the target of family violence was related to the specificity of the adolescents' memories for family disagreements. Orbach and colleagues noted that, compared to children in a control group, children exposed to family violence were more likely to omit responses to questions. They thus avoided providing any responses, either overgeneral or specific. In addition, overgeneral memory was positively related to depression. Finally, Kuyken et al. (2006) reported greater specificity of autobiographical memory in adolescent trauma victims compared to controls.

These studies suggest that mere exposure to trauma is not a sufficient or consistent predictor of overgeneral memory. It is possible, however, that levels of trauma in the key groups of some of these studies were insufficient in strength to detect a trauma influence on autobiographical memory or to reverse the more typical trend. Other research suggests the relation between trauma and memory specificity may be influenced by more qualitative characteristics of abuse (e.g., age of onset, duration, relationship to the abuser). Negative relations have been reported between autobiographical memory specificity and abuse severity (de Decker, Hermans, Raes, & Eelen, 2003), duration of abuse (Burnside et al., 2004), age of onset (Hermans et al., 2004), subjective distress related to abuse (Hermans et al., 2004), and abuse perpetrated by close relatives (Henderson et al., 2002). Furthermore, in a study with Vietnam War veterans, some of whom had PTSD and some of whom did not, strong positive relations emerged between overgeneral memory and PTSD symptoms, but not combat exposure (McNally et al., 1994; but see McNally et al., 2006). This research suggests that the qualitative nature of traumatic experiences is potentially more important than the objective presence of trauma in determining the relation between trauma and autobiographical memory.

Conclusions from this body of research must be drawn with caution. Many of the studies are fraught with methodological limitations, such as the absence of essential control groups, inclusion of control or comparison groups that were not screened for psychopathology, broadly defined trauma groups that span myriad trauma categories, absence of measures of general verbal fluency, gender confounds, and retrospectively self-reported trauma histories without documentation of abuse. Moreover, overgeneral memory has primarily been tested using the Autobiographical Memory Test (Williams & Broadbent, 1986), so that the generalizability of the findings to other tasks is largely unknown. Williams et al. (2007) recently suggested that other tasks should be employed. Furthermore, the causal mechanisms underlying the reduced autobiographical memory specificity remain unclear, although impressive progress has been made in that regard (Williams et al., 2007).

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