Like many other aphantasics below, just my eyelids. It’s ironic because I’ve always had really good (better than 20:20) eyesight, but I can only remember words.
The dreaming question is really fascinating: it doesn’t seem to be impacted in its essence by all the incredibly diverse structures of inner experience. It’s clearly a function of the brain much older than conscious experience [1] and I’ve also read research supporting its necessary role in learning (roughly equivalent to reinforcement learning on synthetic data). There are very rare periods in my life when I’ve remembered my dreams often—-which definitely suggests it’s a skill I could refine—-but generally I recall one or two a year.
One of the interesting questions is which properties of inner experience are genetic, which early developmental, and which skills one can refine at any point in life. Before I knew I was aphantasic, I had a phase studying chess and I tried so hard to “get better” at visualizing games—-one of the most frustrating experiences of my life! Knowing one’s limitations, you can then refine appropriate techniques like algebraic representations etc.
[1] GPT found some terrific papers on this question. In fact, dreaming (measured by two-phase REM sleep cycles) goes back to vertebrates — and seems to have been convergently evolved in insects and cephalopods. Jellyfish appear as the limit with only a single sleep phase. https://www.nature.com/articles/s41586-023-06203-4 is fascinating.
The dreaming question is really fascinating: it doesn’t seem to be impacted in its essence by all the incredibly diverse structures of inner experience. It’s clearly a function of the brain much older than conscious experience [1] and I’ve also read research supporting its necessary role in learning (roughly equivalent to reinforcement learning on synthetic data). There are very rare periods in my life when I’ve remembered my dreams often—-which definitely suggests it’s a skill I could refine—-but generally I recall one or two a year.
One of the interesting questions is which properties of inner experience are genetic, which early developmental, and which skills one can refine at any point in life. Before I knew I was aphantasic, I had a phase studying chess and I tried so hard to “get better” at visualizing games—-one of the most frustrating experiences of my life! Knowing one’s limitations, you can then refine appropriate techniques like algebraic representations etc.
[1] GPT found some terrific papers on this question. In fact, dreaming (measured by two-phase REM sleep cycles) goes back to vertebrates — and seems to have been convergently evolved in insects and cephalopods. Jellyfish appear as the limit with only a single sleep phase. https://www.nature.com/articles/s41586-023-06203-4 is fascinating.