رفتاردرمانی شناختی در مقابل حساسیت زدایی حرکات چشم و بازپردازش برای اختلال پس از ضربه
|کد مقاله||سال انتشار||مقاله انگلیسی||ترجمه فارسی||تعداد کلمات|
|30040||2012||8 صفحه PDF||سفارش دهید||6878 کلمه|
Publisher : Elsevier - Science Direct (الزویر - ساینس دایرکت)
Journal : European Review of Applied Psychology, Volume 62, Issue 4, October 2012, Pages 253–260
Introduction Treatment of choice for post-traumatic stress disorder (PTSD) is either eye movement desensitization and reprocessing (EMDR) or trauma-focused cognitive behaviour therapy (TFCBT). Objective The aim of the present meta-analysis was to determine whether there are any differences between these two treatments with respect to efficacy and efficiency in treating PTSD. Method We performed a comprehensive literature search using several electronic search engines as well as manual searches of other review papers. Eight original studies involving 227 participants were identified in this manner. Results There were no differences between EMDR and TFCBT on measures of PTSD. However, there was a significant advantage for EMDR over TFCBT in reducing depression (Hedge's g = 0.63). The analysis also indicated a difference in the prescribed homework between the treatments. Meta-regression analyses were conducted to examine the relationship between hours of homework and gains in depression and PTSD symptoms. Conclusion These findings are discussed in terms of efficacy and cost-effectiveness and the use of homework in therapy.
The recommended first line treatment for post-traumatic stress disorder (PTSD) is either eye movement desensitization and reprocessing (EMDR) or trauma-focused cognitive behaviour therapy (TFCBT; Bisson & Andrew, 2009). These two therapies work well when compared with a wait-list control (Hogberg et al., 2006 and Resick et al., 2002) against other forms of accepted practices for PTSD (e.g. supported counselling; Foa et al., 1999) and also when they are directly compared against each other (Devilly and Spence, 1999 and Rothbaum et al., 2005). This attests to the robustness of findings for both. Currently the mechanism of action for the effectiveness of EMDR remains controversial, hence it has been suggested that EMDR is a variant of TFCBT as both share key elements of exposure and cognitive processing (Australian Centre for Posttraumatic Mental Health, 2007 and Lohr et al., 1998). Similarities between the two approaches include a cognitive component, imaginal templating (rehearsal of coping responses to future stressors) and exposure (Lohr et al., 1998). However, these differences are superficial especially if one considers the procedures and the assumed processes that are involved. According to Shapiro (2001), EMDR alleviates distress by facilitating access to the traumatic memory network and allowing this consolidation to occur by forging associations between the traumatic memory and more adaptive memories or information. The memory of the traumatic event is initially accessed by having the client identify the dominant visual image, associated negative cognitions, affect and body sensations as well as a more positive and adaptive cognition. Whilst the client focuses on these images, negative cognitions affect and body sensations, they simultaneously engage in therapist directed eye movements for approximately 24 seconds. Associations are then elicited and they become the focus of the next set of dual-attention processing. This sequence is repeated numerous times throughout the session, following standardised procedures with the associations usually becoming more and more adaptive as the session progresses. When the initial memory no longer triggers any distress and the client is able to endorse an associated positive self-referencing cognition, the process is repeated with related current triggers and future apprehensions, ensuring that all past, present and future aspects of the memory network are fully resolved and transformed (Shapiro, 2001). TFCBT utilises traditional techniques of exposure which can be accomplished via systematic desensitization whereby the client is taught to pair the traumatic memory with anxigoenic-incompatible behaviour, such as slow breathing (Brewer, 2001) or prolonged exposure (PE) which involves direct confrontation with the threatening stimulus (Foa & Rothbaum, 1998). Avoidance is prevented at all costs to ensure habituation occurs. Exposure in this instance is long and sustained, requiring patients to relive the memory or confront the threat for at least 60 minutes duration in session and then also for homework. In contrast, although reliving often occurs during EMDR the dual attention processing eventually creates a sense of distance and mindfulness (Lee et al., 2006). The occurrence of free association is thought to demonstrate successful consolidation between the event and the client's current knowledge networks (Lee et al., 2006 and Rogers and Silver, 2002). These processes would be considered avoidance in PE and a hindrance to treatment progress (Foa & Rothbaum, 1998). How these mechanisms, in particular the eye movements aid the therapeutic process is uncertain, though some proponents suggest that there is a psychophysiological response with respect to autonomic changes (Elofsson et al., 2008 and Sack et al., 2008), for more information. Perhaps the most researched and supported model for the mechanism of eye movements in EMDR is the working memory model. This model assumes that because the two tasks of focusing on a distressing memory and making eye movements is sufficient to tax the working memory system during retrieval – the vividness and emotionality of the visual images is reduced (Engelhard et al., 2010 and van den Hout et al., 2011). This was confirmed by Gunter and Bodner (2008) who found that participants who engaged in eye movements whilst holding an unpleasant memory in mind experienced a reduction in vividness, emotionality and completeness compared with those participants who engaged in eye movements after thinking about the event. This degraded memory is thought to be more agreeable to focus on and thus reprocessing can occur. The degraded memory may also elicit other memories (free association) hence allowing further integration. According to the working memory model though, any task that can sufficiently stretch the resources of the working memory pool can be used to disrupt traumatic memories, consequently the eye movements cannot be considered to have a unique effect as drawing complex shapes has been found to also decrease the vividness of emotional memories (Gunter & Bodner, 2008). Perhaps what may be unique about the eye movements is their ability to reduce the distressing nature of “flashfowards” – vivid and emotional images about feared future events. Engelhard et al. (2010) explored this in a non-clinical sample whose ratings for feared future images significantly decreased in vividness and emotionality during the eye movement condition and not in the no dual task condition. Whichever it may be, there is now mounting evidence for the role of eye movements in EMDR and therefore further evidence that it is not a variant of CBT-based approaches. The fact that there is little to no homework assigned in EMDR is also puzzling, as homework is considered to be a necessary and vital component of most psychotherapeutic endeavours, particularly CBT. A recent a meta-analysis by Kazantzis, Whittington and Dattilio (2010) of 46 studies (n = 1.072), directly contrasting therapies with and without homework produced a small to medium effect size in favour of therapy with homework. The authors conclude that homework assignments are clearly beneficial and increase the effectiveness of therapies, which are already clinically robust. This conclusion may not be applicable to all treatments though. Indeed the meta-analysis by Kazantzis et al. (2010) did not include studies of EMDR, a treatment known for its minimal homework requirements. Studies comparing CBT and EMDR reveal number of sessions to be comparable ( Lee et al., 2002 and Power et al., 2002), as well as treatment outcomes (in some cases EMDR has proven to be superior e.g. Ironson, Freund, Strauss, & Williams, 2002) however hours of homework assigned to the study participants are not. The homework component in EMDR has never before been systematically studied. Presumptions insisting that EMDR is more efficient sprung from an earlier meta-analysis by Van Etten and Taylor (1998) who concluded that although the effect sizes were equivalent in CBT and EMDR, number of sessions in EMDR was significantly fewer. However, this analysis did not restrict itself to studies that compared each therapy under identical conditions. A meta-analysis by Seidler and Wagner (2006) was conducted to rectify this issue and only randomised control trials that contained each treatments was included in the data. They found no advantage for one treatment approach over the other. They also did not venture into investigating the “efficiency” statement put forth by Van Etten and Taylor (1998) as there was significant heterogeneity in their results. Since the publication of Seidler and Wagner's (2006) paper, there have been more studies, which directly compare EMDR and TFCBT. This allows for active-active comparisons and as such, it seemed appropriate to conduct a new meta-analysis, the aim of which is to compare the treatment outcomes of EMDR with exposure-based CBT treatments for PTSD. Homework hours will be used as a moderator variable to investigate the extent to which it influences the validity of which treatment may be more efficient. It is proposed that an exploration of this discrepancy could offer further insights into EMDR and add to the conjecture on whether EMDR is a variant of TFCBT, or a distinct treatment modality with its own key processes and mechanisms.
نتیجه گیری انگلیسی
The eight studies comparing EMDR with exposure based CBT refer to a total of 227 participants (116 in the EMDR condition and 111 in the CBT condition; average age = 35.64). Out of the eight studies, seven were not trauma specific populations (i.e. participants reported a range of different and sometimes multiple trauma experiences), and one study was limited to female victims of rape (Rothbaum et al., 2005).