The well-established CHC (Cattell-Horn-Carroll) theory of general intelligence (g) uses a statistical technique called factor analysis to reveal a second level of ‘broad ability’ factors below the level of the g factor. These include visual intelligence (Gv), crystallized intelligence (Gc), fluid intelligence (Gf), working memory (Gwm) and processing speed (Gs).
The broad ability with a highest ‘g loading’ (i.e. the best predictor of the g factor) is fluid intelligence. Working memory capacity (Gwm) also has a high g-loading. Many studies have shown working memory predicts fluid intelligence (and g) to a high extent; in some studies they appear to be virtually the same ability.
What is the difference between short term memory and working memory?
Working memory and short term memory are related, but they have distinct definitions in cognitive neuroscience – although they are both aspects of the same underlying factor of general intelligence – Gwm.
A precise definition of short term memory is given by the Dr Kevin McGrew, Director of the Institute for Applied Psychometrics:
The ability to apprehend and maintain awareness of a limited number of elements of information in the immediate situation (events that occurred in the last minute or so). A limited-capacity system that loses information quickly through the decay of memory traces, unless an individual activates other cognitive resources to maintain the information in immediate awareness.
We use our limited capacity short-term memory for:
- remembering a telephone number before dialing it or writing it down
- remembering what you have to get when you go shopping
Typically the capacity of short term memory is 7 plus or minus 2 items or ‘chunks’ of unrelated information.
What is Working Memory?
But more important than just holding information in mind is being able to process that information – to solve a problem, to figure something out, or reason through something to find an answer – while potentially multi-tasking with other less demanding tasks such as driving or while having to focus to filter out distracting information. The more complex system that allows us to do all this is working memory.
Working memory (WM) is a primary cognitive function that corresponds to the ability to update, stably maintain, and manipulate information in short-term memory rapidly to perform ongoing cognitive tasks. We use working memory (WM) in our daily lives to perform a multiplicity of high-level cognitive tasks, like planning, speaking, reasoning, language comprehension, and thinking. Working memory load is strongly connected to the experienced mental workload.
Working memory can be thought of as our ‘mental workspace’. People differ in the capacity or ‘bandwidth’ of their working memory. Differences in working memory capacity (WMC) strongly predict IQ levels.
What is Working Memory Capacity?
While average capacity of working memory is much less than 7. Most people have a working memory capacity of about 2 or 3. IQ Mindware dual n-back apps are designed to
The Working Memory Capacity – IQ Link
General intelligence depends on working memory capacity because working memory capacity is needed for relational reasoning – while connecting information in novel ways – which is at the core of fluid intelligence. Fuid intelligence and working memory operate together as a kind of limited capacity central processor of our intelligence. The G CODE brain training system targets this combination in its fluid intelligence (IQ) training.
Tests of Working Memory
The n-back game – as used in HighIQPro and DNB Pro – itself is a test of working memory capacity. The complex span test in the HRP Track cognitive testing app is one of the most widely used, valid tests of working memory.
References
Kyllonen, P. C., & Christal, R. E. (1990). Reasoning ability is (little more than) working-memory capacity?! Intelligence, 14(4), 389–433.
McGrew, K. S. (2009). Intelligence 37, 1–10.
McGrew, K. S. (2009). CHC theory and the human cognitive abilities project: Standing on the shoulders of the giants of psychometric intelligence research. Intelligence, 37(1), 1–10.