Human channel capacity increases with bits-per-chunk. But we don’t need to rely on the “intrinsic” chunk size of a stimulus. It’s possible to increase the effective chunk size of stimuli by recoding them—that is, mentally regrouping them into chunks representing larger patterns. These chunk schemas are also called Mental representations, after Ericsson and Pool.
For example, when trying to memorize a sequence of binary digits, one can instead memorize them as octets (e.g. 010 = 2, 101 = 5, etc), which will roughly triple your capacity (Miller, 1956). Chase and Ericsson (1982) used this technique to build a student’s digit span to 80 digits, via hierarchical recoding into 4-decimal-digit chunks.
This process is important not just because it helps us remember useful information, but because it’s likely the key to how anyone processes any kind of complex material (in particular, Expertise requires building sophisticated chunk recoding schemes). A pianist initially reads individual notes (C, E, G—ah, a C chord!) but later sees that shape as a single chord (ah, a C major triad). It’s not possible to sight-read music of any real complexity with the former-approach.
These patterns (e.g. the shape of a major triad) can only be used as “chunks” once they’re stored in long-term memory.
Chase and Simon - Perception in chess record experimental data suggesting that chess masters use larger chunk sizes (and possibly hierarchical chunk configurations).
Related: Complex ideas may be hard to learn in part because their components overflow working memory
Chase, W. G., & Ericsson, K. A. (1982). Skill and Working Memory. In G. H. Bower (Ed.), Psychology of Learning and Motivation (Vol. 16, pp. 1–58). Academic Press. https://doi.org/10.1016/S0079-7421(08)60546-0
Miller, G. A. (1956). The magical number seven, plus or minus two: Some limits on our capacity for processing information. Psychological Review, 63(2), 81–97. https://doi.org/10.1037/h0043158 Miller - The magical number seven, plus or minus two
In many fields, experts become experts mostly by developing more sophisticated mental representations (Mental representations, after Ericsson and Pool), which amounts to increasing the size of their mental chunks (“Chunks” in human cognition). This increases their information processing capacity (Human channel capacity increases with bits-per-chunk, Recoding can increase chunk size). This happens through practice: Good practice encodes more effective chunk recoding schemes
What sets expert performers apart from everyone else is the quality and quantity of their mental representations.
(Ericsson and Pool, 2016, p. 62, not well-cited)
For example, the model developed by Simon and Gilmartin (1973) suggests that chess masters have encoded order tens of thousands of chunks. (See also Chase and Simon - Perception in chess)
Knowledge work often requires solving search problems. Ericsson and Pool suggest that expert search performance comes from more complex chunk schemas (2016, p. 70-72). The argument’s not made very strongly, but because Human channel capacity increases with bits-per-chunk, this would seem to explain superior culling and feedback-uptake performance.
Simon, H. A., & Gilmartin, K. (1973). A simulation of memory for chess positions. Cognitive Psychology, 5(1), 29–46. https://doi.org/10.1016/0010-0285(73)90024-8
Ericsson, A., & Pool, R. (2016). Peak: Secrets from the New Science of Expertise (1 edition). Eamon Dolan/Houghton Mifflin Harcourt. Peak - Ericsson and Pool