Persistence as one of the “seven sins of memory” stands out as the most interesting, whereas intrusive memories of events that an individual wishes to forget permeate a person‘s state of being, unlike the other six. In transience, absent-mindedness, and blocking a person forgets events that he or she wishes to recollect. In suggestibility, bias, and misattribution one distorts events, items, people, etc… The contribution of cognitive, social, and clinical psychology has shed light on all these “sins” of memory, blending to create a basis for the understanding of memory as it relates to both brain and behavior. For clinical psychologists, persistence is the most troublesome and most likely the most problematic for clients. Persistence, also, seems to stand out as a direct opposite of blocking, whereas a person knows that knowledge of some event exists, but they are temporarily unable to retrieve that information. In persistence, negative memories and/or states of mind intrude thinking and in essence block positive memories and modes of positive mood.
Examples used to explain the phenomenon of persistence is the study of PTSD patients, who were victims of abuse and the control group, who experienced the same type of trauma, but did not meet the clinical diagnosis for PTSD. In a “direct-forgetting” study, both groups were told to forget trauma-related words and to remember words un-related to trauma. The control group did remember more of the un-related words, while the experimental group did not exhibit “direct-forgetting” and instead did recall the trauma-related words more than the words they were instructed to remember. Under similar lines, depressed patients were more likely in a study after ruminating on their current state of mind and mood to recall depressing autobiographical events when asked to do so. The group that was not depressed was much less likely to recall negative past events after thinking of their more positive mood and state. These studies are very important in understanding why depression, phobias, and other negative states of being permeate and persist in an individual.
I believe that many persons with PTSD make great effort to avoid situations that remind him or her of their trauma, but persistence is so rooted in the limbic system (where fear-inducing responses originate), natural and personal effort will usually fail. The memories will persist in the form of nightmares (which are rooted in the subconscious therefore beyond the sufferers control) or certain cues (such as memory-related smells, tastes, or other sensory events), therefore making the task of forgetting negatives in order to remember positives requiring retraining. In my opinion Systematic Desensitization is the best way to recover all negative cues and memories related to a trauma for an individual and then to require rumination on the negative event to the point that they do not become intrusive. But, it is from my experience a difficult task, as one must unlearn unhealthy behaviors that make functioning difficult and re-learn how to think and, in essence how to feel healthy again. Writing is a great way for trauma and negative thought patterns that seemed to almost be trapped in the mind to emerge in a new medium that is more in control for the sufferer.