🏷️ Categories: Memory, Creativity, History
One morning, a young musician woke up with a melody echoing in his mind. It was a catchy whisper that he couldn't stop humming. However, there was something unsettling about that melody; it sounded familiar, perhaps too familiar not to have heard it before. With his mind still foggy from sleep, he sat down in front of the piano and let the notes flow.
The more he listened to it, the better it sounded.
Was it someone's?
It was one of those questions we don't really want to know the answer to: was it an unconscious recollection of his memory or a genuine product of his dream? For this musician, music was sacred and he didn't want to spoil your passion and career by being accused of plagiarism. With doubts, he wrote the dream melody and left home in search of answers.
He fearfully entered the first music store he saw.
He hurriedly rummaged through the vinyls, trying to remember, but no record reminded him of the melody of his dream. For weeks, store after store, the young musician anxiously searched for the answer to his question. Was it an original or a fuzzy memory? Finally, after a month of fruitless searching, he made the final decision. That beautiful melody would be his and he would make lyrics to match.
In time, the song became a milestone in his career and catapulted him to fame as a musician. All thanks to a fleeting glimmer that flashed through his mind one night.
This story is true.
That song is “Yesterday” and that musician was Paul McCartney.
Random access to memory
The human brain is not like a music player, it's like a musician. You see.
The brain has random access to information, that is, there is no linear path. You can remember things in any order, first memories from your childhood, then from this summer, then from several years ago. It's not like old cassettes, where you listen to songs in a fixed order.
But memory has a problem.
That, unlike cassettes, memory doesn't always play the same. The memory is similar, but never the same. Your memory is like a musician: he can play the same song a thousand times, but no two songs will ever be identical.
The role of sleep in memory and creativity
What happened to Paul McCartney is possible because during the NREM phase of sleep, our brain consolidates what happened during the day as memories (Walker, 2009). Later at night, during the REM phase, the brain relates those new memories to previous memory (Stickgold et al., 1999), which helps to find creative solutions to abstract problems (Walker et al., 2002; Wagner et al., 2004).
See where I'm going?
Beatles biographers believe that in his dream, Paul McCartney replayed a warped memory mixed with many previous musical experiences, which caused him to dream up a new tune (Cross, 2005; Turner, 2005).
Memory is malleable (and very much so)
You have details to reconstruct memories, but not exact memories (Schacter, 1982).
First you remember the yellow square, but as time goes by, you begin to doubt whether it was yellow or brown. After a long time without remembering that fact, someone asks you if it was a triangle or a square that you saw. Their question puts you in doubt and in the end you think you saw a brown triangle and not a yellow square.
Just like that you generate false resources. About this, I know two shocking experiments, the STOP experiment and the hot air balloon experiment.
Neuronal pruning
Neuronal pruning is the process of eliminating underactive neuronal connections (Cardozo & Alzate, 2016). When a memory stops being activated for a certain period of time, the brain begins to prune those neurons and forget information. On the contrary, during sleep the neurons that you have used the most strengthen their connections.
Perhaps this is why McCartney could not remember the source of his inspiration, after a long time, he had suffered some neuronal pruning.
In this whole process there is a key piece: the dendritic spines.
They are like the little twigs that grow on the thick branches of trees. They are small spikes that are around neurons and that connect, forming new connections and storing everything you learn (De Roo et al., 2008). In the end, the brain is a tree that, over the years, needs to have old branches pruned off to make way for new branches and keep the tree growing vigorously.
Isn't it great how Mental Garden resembles neuronal pruning?
I love this psychological concept.
✍️ Your turn: Have your dreams ever given you great ideas?
💭 Quote of the day: “Those who dream by day know many things that escape those who dream only by night.” Edgar Allan Poe, The Tell-Tale Heart and Other Writings.
See you next time! 👋
References 📚
Cardozo, M. O., & Alzate, O. E. T. (2016). Bases moleculares de la memoria y su relación con el aprendizaje. Archivos de Medicina (Manizales), 16(2), 467-484. https://doi.org/10.30554/archmed.16.2.1724.2016
Cross, C. (2005). The Beatles: Day-By-Day, Song-By-Song, Record-By-Record.
De Roo, M., Klauser, P., & Muller, D. (2008). LTP Promotes a Selective Long-Term Stabilization and Clustering of Dendritic Spines. PLoS Biology, 6(9), e219. https://doi.org/10.1371/journal.pbio.0060219
Schacter, D. L. (1982). Stranger Behind the Engram: Theories of Memory and the Psychology of Science.
Stickgold, R., Scott, L., Rittenhouse, C., & Hobson, J. A. (1999). Sleep-Induced Changes in Associative Memory. Journal Of Cognitive Neuroscience, 11(2), 182-193. https://doi.org/10.1162/089892999563319
Turner, S. (2005). A Hard Day’s Write, 3e: The Stories Behind Every Beatles Song. It Books.
Wagner, U., Gais, S., Haider, H., Verleger, R., & Born, J. (2004). Sleep inspires insight. Nature, 427(6972), 352-355. https://doi.org/10.1038/nature02223
Walker, M. P. (2009). The Role of Slow Wave Sleep in Memory Processing. Journal Of Clinical Sleep Medicine, 5(2 suppl). https://doi.org/10.5664/jcsm.5.2s.s20
Walker, M. P., Liston, C., Hobson, J., & Stickgold, R. (2002). Cognitive flexibility across the sleep–wake cycle: REM-sleep enhancement of anagram problem solving. Cognitive Brain Research, 14(3), 317-324. https://doi.org/10.1016/s0926-6410(02)00134-9
It's interesting how memories can be triggered by some arcane daily moment: a song playing on the radio, a smell, or someone mentioning a name that recalls a strong experience way in the past. The memories may be pruned, but with a little water, they grow back with renewed vigor if not the same twigs and blossoms as in previous versions. As an old lady, I'm recalling many experiences to write about ... it's my stock in trade. Some ideas are so pruned, I have to graft new information on them to make them balanced. Pardon me, Alvaro, I'm having too much fun with this metaphor. Anyway, a lot of the stories on my page are graftings from the past.
Beautiful column and a marvelous example. Thank you.