Chapter 4. Why does Dissociation Occur ? (11)

Apart from the epidemiological difference, clinical picture of DID in the US is very similar to that in Japan. The age of onset, gender difference, and different identities’ number, gender, age distributions are largely comparable in these two groups. The prevalence of DID seems to be also similar in two countries, at least based on my personal experiences (Okano, 2007) The families of origin of DID patients in the US are often chaotic, especially when childhood abuse is involved. On the other hand, Japanese DID patients’ families of origin are generally intact. In the initial assessment sessions, patients are often escorted by their parents who listen attentively to the evaluation process when they are allowed to do so. Things are quite different in American cases where the fathers, the main abusers involved have long been gone. Patients usually come to the initial sessions by themselves or chaperoned by their significant others.
If the incidents of childhood sexual abuse is grossly smaller among Japanese daughters are much smaller the household in Japan, what might explain the typical gender difference of DID? Is it because biologically women are more prone to dissociative pathology? Or the defense mechanism of dissociation more frequently used by female? This needs further analysis.
Dissociation as a result of traumatic stress
Although many authorities indicate strong relationship between DID and trauma, unlike PTSD their causal relationship remains largely speculative because of the nature of the trauma. In PTSD, typically a single trauma is involved, which occurs often in adulthood, within several weeks prior to the onset of PTSD. In many cases, traumatic incidents are objectively identifiable. As an example, there is a report that about 500 school students are still suffering from PTSD ten years after the Hanshin Awaji Earthquake. (Kyodo Tsushin, 11/10, 2006.) In this case, we know exactly when and how the traumatic event (the earthquake) happened. However, in DID, trauma should have occurred long time ago in the patients’ childhood and often the patients’ host personalities are not aware of the incidents.