Working memory limits

A working memory is a part of our cognitive system where we hold temporary information and process them. There are limits to our working memory:

1. How long we can hold the information (Information in working memory decays, see: How long would information stays in short-term memory?)
2. How many pieces of information we can hold and process

There are a couple of answers to how many information we can hold and process. Many references would refer to the number 7 (Miller). A more recent study points that our limit is more like a maximum of 4 (Cowan).

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References

Goldstein, Cognitive Psychology (p. 135).

Mathy and Feldman (2012) therefore claimed that the true limit of STM capacity is more likely to be four than seven. This is in accordance with outcomes of experiments using a change detection paradigm to study visual short-term memory.

Goldstein, Cognitive Psychology (p. 138).

There is, however, agreement that whether considering items or information, the upper limit for short-term memory capacity is about three to four items.

Ahrens, How to Take Smart Notes (p. 68).

Our short-term memory is also limited. We need strategies not to waste its capacity with thoughts we can better delegate to an external system. While the estimations of our long-term memory capacity are wildly diverse and rather speculative, psychologists used to tend to agree on a very specific number when it came to short-term memory: We can hold a maximum of seven things in our head at the same time, plus/minus two (Miller 1956).

Miller, George A. ‘The Magical Number Seven, plus or Minus Two: Some Limits on Our Capacity for Processing Information.’ Psychological Review, vol. 63, no. 2, 1956, pp. 81–97. DOI.org (Crossref), doi:10.1037/h0043158.

Cowan, Nelson. ‘The Magical Number 4 in Short-Term Memory: A Reconsideration of Mental Storage Capacity’. Behavioral and Brain Sciences, vol. 24, no. 1, Feb. 2001, pp. 87–114. DOI.org (Crossref), doi:10.1017/S0140525X01003922.

Scientific Secrets for Raising Kids Who Thrive Audiobook | Peter M. Vishton, The Great Courses | Audible.co.uk (opens new window) (Downloadable PDF)

We have a short-term memory that is limited in size to something like seven digits, words, or other units. The only way to hang on to information for a longer time period is to create a more durable representation, either by writing it down or encoding a long-term memory of it.

Backlinks

• Writing makes thinking possible
  • We need a good method to think because we have Working memory limits. If Effective tool circumvents human limits, we need to find a tool that circumvents our working memory limit. The tool, or method of thinking that has been proven by science is note-writing. Many would think that writing helps our thinking, but contemporary handbook of neuroscientists argues that writing is what makes thinking possible. Scientists with different specialisation, like psychologists, educators, or philosophers, may disagree on how our brain works, but most of them agree that real thinking will require a form of writing (Ahrens 95-96).
• Humans are constrained by biological limits
  • Whether we like or not, we are all constrained by our biological limits. We have Working memory limits, we can’t imagine a five-dimensional cube, and our circadian rhythm will tell our sleep pattern. Even Usain Bolt can’t outrun a domestic cat.
• Writing allows us to deliberately forget
  • We have Working memory limits, therefore making sure that we can populate our working memory with what's relevant in the current circumstances is necessary for us to be effective. Unfortunately we don't really have a full control over what we have in our working memory, other irrelevant thoughts might linger (like open tasks) and will reduce our ability to focus. (See also: Zeigarnik Effect)
• Chunking increases working memory capacity
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• Cognitive functions have a limited capacity
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• To write is to rubber duck
  • Perhaps, one reason I felt stuck is because there are too many variables I’m playing in my head when I was presented with the architectural problem. I was hitting my Working memory limits. By writing them down, it’s as if I have more working memory to play with. Writing makes thinking possible.
• The limits of consciousness
  • Mihaly seems to indicate that this is related to working memory, but I don’t really understand how consciousness is related to the concept of working memory. See Working memory limits.
• The prerequisites of flow are needed to flood working memory
  • The The prerequisites of flow experience are needed to enable continuous concentration on a task. These prerequisites are seemingly related to the fact that we have Working memory limits.
• Attention limits
  • For example, we have Working memory limits, Attention limits.
• Working memory is limited to four chunks
  • See Working memory limits.
• Negative thoughts consumes working memory capacity
  • Given that we have Working memory limits, negative thoughts that linger in our heads also consume that capacity, which means we'll not be able to perform as efficiently as we could (Working memory is efficient when it stores relevant information)
• Developer workflow may improve DevEx
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• How might we use our limited working memory capacity more effectively?
  • We have Working memory limits, therefore knowing how to utilise it well may improve knowledge worker's mental performance.
• Limits of working memory may limit improvements from practice
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• Chunks should be borrowed from experts
  • Given my Working memory limits, I won't be able to pay attention to all of these at the same time. The chunk that I discovered from experts is the word "anticipation".
• Comparing side-by-side circumvents our cognitive limits
  • When windows or screens are rapidly switched, what you're doing is you're committing the details into your working memory, we have Working memory limits, and which make Cognitive load higher.