I recall a schoolboy coming home
Through fields of cane
To a house of tin and timber
And in the sky
A rain of falling cinders
From time to time
The waste memory-wastes
So begins the single titled “Cattle and Cane” released by the Australian rock band “Go Betweens” in 1983. The lyrics capture an adult reminiscing of childhood memories, of boarding school and returning home by train for the long summer vacation somewhere in the north-west of Queensland, Australia. For many, it has become associated with the yearly journey to spend Christmas with family, back to their small-town birth places from some remote large metropolis of their chosen profession.
The dreamy, movie-like sequence evoked represents the recall of a very long term memory. LTM is a declarative memory sub-type, and this verse an example of explicit, episodic memory – personal experiences from a particular time and place. Rich and vivid, not just a complete sensory recollection – golden cane fields, burning cinders, train tracks, tin, rain – but suggestive of mood and emotion.
The circumstance by which such LTM childhood memories are retrieved is in itself interesting. Not something that can be turned on demand, a particular combination of conditions is required. In this case, the relaxed mental state induced by a long, slow train trip together with cues signalled by the spatial and temporal context of the moment were sufficient to trigger the recall.
To be retrieved, the original experience must be encoded and that memory retained. Such LTMs are formed in the hippocampus and stored as strengthened synaptic connections located in those areas that perceived the original experience. These can weaken over time – memory wastes – and so original information is lost. Moreover, the act of retrieval is itself a creative process. The memory is changed and so the original experience is subject to a reinterpretation and resynthesis. Unlike the operations of the well written computer program, a random-access-memory read causes a write.
Like the lyricist, we are the sum of our experiences. Our life story is written in LTM. Personality is shaped by how we perceive our successes and failures, joys and sorrows. Perception formed from information recalled by a process that is far from a neutral observer. Maybe these are the rose tinted glasses of nostalgia, what for the child may have been endless days of boredom, for the adult becomes a time of magical idleness. The vividness of the recollection does not necessarily correlate to precise and reliable fact.