| The problem is multifactorial. There have been studies looking at the relative retention rates of visual vs auditory stimuli where the visual typically comes out ahead: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2667065/
https://scholarworks.iu.edu/journals/index.php/iusburj/artic...
http://journals.plos.org/plosone/article?id=10.1371/journal.... However, I would posit that the main reason for this discrepancy is that memory is linked to the level of stimulation, and we typically have developed to place a far higher weighting on our visual systems, not to mention the fact that the visual signal typically has a far higher information content, linking to many existing mental structures. Once these sort of links are removed, with the stimuli being decontextualized, the two tend to be more similar:
https://link.springer.com/article/10.1007/BF00447078 The problem with audiobooks vs reading is far more constrained, and possibly environmentally determined. One study found that visual vs auditory retention rates for a short block of text were virtually identical:
http://psycnet.apa.org/record/1978-21860-001 But another again shows the superiority of the visual system:
http://scholar.utc.edu/cgi/viewcontent.cgi?article=1171&cont... But this was done in a controlled environment where the subjects' full attention was focused on the audio. In such a case, it makes sense that retention rates would be comparable, as the same language centers in the brain are used for processing the input once it is transferred from the appropriate input sense. The big problem with audiobook retention is that we typically listen to them whilst being involved in other tasks, and there are are a myriad of studies showing that humans are inherently extremely bad multi-taskers, with high task-switching costs even in people who claim to be otherwise. Aside from just sitting with my eyes closed and listening, I find that retention is maximized with audiobooks when there is a split between System 1 and System 2 activity (ala Thinking, Fast and Slow by Daniel Kahneman). If I am doing something like driving, using System 1, my System 2 can be fully focused on the audiobook, until something darts out in the middle of the road and then I end up having to rewind and re-listen to what I missed. |