Page 13 - PIECES OF THE PUZZLE Eline Vissia

Dorahy et al. (2004) recommended that studies in DID need to recognize and cognitively assess various dissociative personality states when studying working memory, since working memory performance may covary with different prototypical dissociative personality states. A cognitive architecture supporting vigilance and bias for threat stimuli is increasingly suggested by studies regarding attention and working memory in DID (Dorahy et al. 2014). The nature of this architecture may vary depending on the characteristics of the dissociative personality state that is assessed (Dale et al. 2008, Dorahy, Middleton & Irwin 2005, Hermans et al. 2006).
Prevalence
Prevalence rates for DID vary widely, which can be largely explained by the choice of diagnostic instrument and cultural differences in symptom interpretation (Friedl, Draijer & de Jonge 2000). The prevalence of DID appears to be highest in emergency psychiatric settings and affects approximately 1% of the general population (Dorahy et al. 2014). The International Society for the Study of Trauma and Dissociation (ISSTD) has reported that the prevalence of DID is between 1% and 3% in the general population, and between 1% and 5% in inpatient groups in Europe and North America (International Society for the Study of Trauma and Dissociation 2011, Van der Hart, Nijenhuis 2009). Cross-cultural consistency of DID is suggested by similar reported symptom profiles in North America (Ross et al. 1990), The Netherlands (Boon, Draijer 1993b), Turkey (Sar, Yargic & Tutkun 1996, Akyuz et al. 1999) and Puerto Rico (Martinez-Taboas 1991).
DID simulation
In a review of studies comparing diagnosed DID with simulated DID (Boysen, VanBergen 2014) it was concluded that results provided more support for a sociocognitive model than for a trauma model (see below for further description of the models). Among others, inter-identity transfer of information was replicated various times using a variety of methods (Allen, Movius 2000, Kong, Allen & Glisky 2008, Huntjens et al. 2006, Huntjens, Verschuere & McNally 2012). This finding can support a skeptical view towards the accuracy of memory experiences among people diagnosed with DID (Boysen, VanBergen 2014). On the other hand, simulators and DID patients showed significant differences on some clinical measures and DID patients showed cognitive deficits in memory
GENERAL INTRODUCTION
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