Most health care professionals involved in eldercare have had the experience that some of those we look after seem to be able to recall past experiences with a degree of intensity that may be very disquieting and may even lead to what gets interpreted as agitated behaviour. These same individuals may have had the personal experience as I have from my own life experience, some memories; even those very distant, when recalled are almost as vivid as when they first occurred. Depending on the nature of the recalled experience, the impact can be calming, soothing and satisfying or very disturbing. On a personal level, when I wrote some of my life stories, which ultimately became my memoir, Brooklyn Beginnings: A Geriatrician's Odyssey, many of the experiences I recounted were so vivid that I could almost hear the voices, smell the smells and taste the flavours that accompanied the experience.
In my primarily ambulatory geriatric medical practice, which focuses heavily on patients with some degree of cognitive impairment and dementia, memories that do get recounted from the distant past sometimes appear to the person to be almost occurring in the present. Family members often remark that the person cannot recall what they had for breakfast but recall in vivid detail the Atlantic crossing from Europe in 1905. My grandmother who helped raised me often told me the story of Cossacks raiding her small Lithuanian village at the turn of the 19th century and killing and maiming many of her friends and neighbours as she and her family huddled in the potato cellar. The story was so vivid to her and almost transferred like a copy of a movie that I have been able to recall it as one would watch an old movie.
Many of my patients are Holocaust survivors. They are often plagued with distant horrific memories that are so vivid when recounted or when they intrude into consciousness that they become agitated, fearful and panicked. They actually believe they are reliving the painful associations with that previous part of their life, which they may have spent many years trying to forget. One of my patients who had been incarcerated in a concentration camp in Poland would recount to his wife in total terror and remorse how he managed to avoid being taken out of the morning roll call on a freezing morning to be shot, but the man, in fact a friend, standing next to him was taken and murdered instead. He kept repeating to his wife, "they took him instead of me, they should have taken me, they should have taken me." His wife said that no matter what she said to him he would not get out of that frame of mind which he told with terror on his face over and over again until he was quite exhausted. Even the use of various medications, eventually resulting in small doses of atypical neuroleptics did not eliminate the experience even though it modified the intensity of his very emotional outbursts. The response to SSRIs and beta-blockers both of which were tried was not impressive. http://www.nature.com/drugdisc/news/articles/436448a.html
With this conscious awareness of how some people, seem to have the propensity to relive certain experiences with great vividness, I was enthralled to see a report in the Journal of Cognitive Neurosciences describing a study using complex FMRI imaging techniques that may help to explain the neurophysiology of vivid memory recall. From this study, undertaken at the Rotman Research Centre of Baycrest with Dr. Bradley Buchsbaum as the primary investigator that it appears the brain keeps in its memory the pathways of different experiences (http://www.sciencedaily.com/releases/2012/07/120723134745.htm). These, when accessed, can repeat the circuitry of the original experience so that the memory is as if that sequence of events is taking place as vividly as in "real time." If this is shown on further studies to be the mechanism for vivid memories, it potentially opens up new ways to treat or prevent vivid memories of terrifying experiences and perhaps even play a role in addressing the mental experience of post-traumatic stress disorder. This observation opens up many avenues for future research and perhaps interventions that may prove therapeutic beyond the current typical cognitive and other combinations of therapies. (http://www.helpguide.org/mental/post_traumatic_stress_disorder_symptoms_treatment.htm).
Derived from article in Canadian Jewish News February 28, 2013.