EPISODIC MEMORY: AN EVOLUTIONARY MARVEL OR A DESIGN FAULT?

 Last week we went to a wedding reception. The parents of the bride are friends of ours. There was a pre-dinner short boat trip on the Thames. On the deck I saw a couple of other people who were mutual friends. We gravitated towards each other and ended up standing together on the deck.

I got busy talking to them but in the back of my mind something kept niggling. While getting on the boat I saw a familiar face but could not put a name or context to it. Who was that man? If I could remember where I met him before, I might be able to put a context and then maybe I could even recall his name. 

To say that you know a person you have to know the context  in addition to name and image.  When we meet a person and have interaction with, the brain acquires all these bits of information and automatically stores them. Unfortunately each bit is retained in a separate place, on top of that, as the time passes they are moved around perpetually depending on the priority our brain assigns them.

How does the brain prioritize, does not enter into our consciousness. Sometime very mundane and banal facts are kept in the fore of the mind and at other times even crucial or apoplectic events are forgotten.  Our brain does not share a lot of things with us! Is it an evolutionary asset or a design fault?    

Forgetting events and people associated with unpleasant or unimportant events certainly keeps us in positive frame of mind but forgetting important episodes puts us at a great disadvantage. The problem is that it is our brain that decides what is important, not our conscious mind. People who had been in rather close contact in past feel hurt when they find out that you cannot recall their names, faces or contexts. They impart blame as if you have “consciously” forgotten them.

Luckily, one of the friends who I was talking with said “have you met Rehman? He is here on the boat.” Suddenly the veil disappeared I remembered him. He worked with us in the same department and lived only a few blocks away. That was  20 yrs ago! All these bits of information were in my brain safely stored, just needed a trigger to bring them to my conscious mind. A few minutes later when he came near us, I met him with all the warmth that my memory has just delivered!

If you think memory is for keeping an accurate record of past, then it is flawed and defective. But as a tool for imagining future scenarios and thus preparing us to face the uncertainties of future better, it is a design marvel. This really is the purpose of memory. 

“Indeed, our ability to revisit the past may be only a design feature of our ability to conceive of the future” Suddendorf & Busby 2003

EVOLUTIONARY PSYCHOLOGY

25/9/09 (Day 30, Retirement)

Today is exactly a month since I retired. It is a milestone for me and probably for my wife too. You might say it is ridiculous to call a month, a milestone but if you take the analogy of a new born baby it becomes obvious. For the parents, a week, a fortnight, a month, all become occasions to celebrate. And the retirement is like a new baby! Delighted to have it but a source of anguish none the less.

I have to be really very watchful; otherwise my physical activity level will rapidly fall down below the critical line. This is because of my inborn aversion to unnecessary & unpleasant physical activity. Before retirement I had to walk a lot, stand a lot, just as a part of the job, but not now. Now I can easily spend the whole of the day just reading, watching tele or surfing on the net. I am fully aware that this will be extremely counterproductive to my health and hence to my plan to draw the pension as long as possible. But apart from that I also feel psychologically unwell when I spend the day without any physical exercise. So with great effort I try to do at least an hour of yoga with an in built physical exercise programme.

Why is physical exercise necessary when it is really no longer needed by the modern life style? I am not talking about obvious physical health problems to my cardiovascular or musculoskeletal systems. I know them well. What I am talking about is the feeling or the sense of being unwell. I have been searching the internet for the enlightenment. Where else? And I think the answer is in Evolutionary Psychology (EP). I came across this term as I was looking at today's news headlines at BBC website. The news was that there will be more spiders this year due to favourable breeding conditions caused by temperate summer. There was a link to arachnophobia on the page and from there another link and so on till I reached EP.

Just as Darwin's physical evolution which selects certain physical attributes which are advantageous to the organism during a prolonged period of particular environmental pressures there is psychological evolution, whereby a set of necessary psychological adaptations to combat the recurring pressures of prolonged ancestral environment becomes part of the developmental nature. A good example of this is fear of spiders or snakes. A recent study from US published in New Scientist remarked that women have a genetic aversion to dangerous animals such as spiders. Spider phobia is much more common in females than males. This is because their ancestral role as a new born protector. Overtime they developed a natural aversion to any animal which can sneak in and may be dangerous to their baby. Baby girls showed this as early as 11 months of age compared to baby boys. EP also explains why men and women look for different attributes in choosing a life partner.

This feeling of being unwell is also due to ancestral pressures during a period when not being able to do strong manual tasks was fatal. Overtime our brain developed in a way that it automatically creates an unpleasant sensation when you do not do the minimum required physical activity.

Well that is what I think anyway. And now I have to go to do my yoga which I conveniently forgot this morning. I am looking forward to your thoughts. Bye for now.