How do our memories form our sense of who we are? Katie Scott considers
My sister looks at me with one eyebrow raised. ‘Can you really not remember that?’ she asks. I shake my head. I’m sure it did happen – she recalls details that make me laugh and recounts things that I did that I know are true-to-form – but my mind is blank.
I’m forty-two and pride myself on a pretty good memory. I can recall names of people I haven’t seen for decades. And yet so many of the childhood memories my sister remembers, I just can’t. They must be in my head somewhere. And they must play a part every day in what and who I think I am.
Memory and its relationship with our perception of self has been a fascination for centuries. The seventeenth-century philosopher John Locke declared that we are born as ‘tabula rasa’ – a blank slate – then shaped by our experiences and how they made us feel. Being able to access ‘this succession of perceptions’ – to recall our memories and relate them to ourselves – fellow philosopher David Hume hailed as ‘the source of personal identity’.
In Scientific American, Robert Martone articulated this beautifully: ‘We are all time travellers. Each day, we experience new things as we travel forward through time. In the process, the countless connections between the nerve cells in our brain recalibrate to accommodate these experiences. It’s as if we reassemble ourselves daily, maintaining a mental construct of ourselves in physical time, and the glue that holds together our core identity is memory.’ Self-referencing memories, Martone noted, are recalled more easily and are at the core of our sense of self.
In general terms, our long-term memory is contained in two systems: declarative and procedural. Within the declarative, said experimental psychologist and cognitive neuroscientist Endel Tulving, are the episodic and semantic systems. The latter contains factual memories and knowledge, like times tables or capital cities. Facts about ourselves – where we were born, for example – sit here. It’s also a trait library: a database of how we reacted in particular situations and therefore a reference for how we might react again.
But it is the episodic memories, wrote psychologists Shaun Nichols and Stanley B Klein, that represent the ‘what, whens and wheres’: the colourful memories that ‘seem to be essential for the sense of personal identity across time’. By revisiting these memories, we put together our life stories. I am a mother now – but I am also the child who used to sit on the stairs waiting for my dad to come home from the airport.
Memories bond us to others. We used to have bonfires by a rickety old shed at the end of our garden; I remember sitting there between my brother and sister while we swapped tales of the naughty things they did at school. I remember the place, the smells, the conversation, the laughter and the feeling of belonging. It may have been twenty years ago, but that memory speaks of my relationship with them: how they view me and how I view myself through their eyes.
Memories enable us to consider our actions in the present and determine how we might act in future. We can learn from mistakes we have made. ‘The parts of the brain that interpret experiences and the parts of the brain that create memory all communicate,’ wrote psychologist Dr Kevin Hull, ‘so that a seamless stream of experiences and memories is constantly being formed. The result is a person that learns from mistakes, overcomes shame and guilt by remembering [having] made positive choices and recognises positive parts of herself.’
It also enables mental time travel. ‘We visit the past through our memories,’ said Martone, ‘and then journey into the future by imagining what tomorrow or next year might bring.’
The evening after I had seen my sister, I tried to remember the incident she had recounted. It didn’t appear but many other memories did, prompted by association. I thought about how every memory – of whatever kind, whether good or bad – is an almost imperceptible stroke in my portrait. My memories don’t define me, but they are me. They represent a mental map of what I have done, seen, felt and known. I may not recall everything, but those I love recall the other things. And so we share our memories, and every day is an opportunity to make more.
