Short-term memory holds information; working memory holds and uses it
| Term | Central function | Example |
|---|---|---|
| Short-term memory | Hold information temporarily | Repeat spoken digits in the same order |
| Working memory | Hold information while using it in current processing | Retain an intermediate result while continuing mental arithmetic |
Working memory also requires temporary storage, so the two overlap substantially. They are better distinguished by what processing is added to retained information than treated as two completely separate stores.
The difference appears in what is added to maintenance
Remembering a room number until reaching the door is mainly maintenance. Putting digits in ascending order adds manipulation, replacing an old meeting location with a new one adds updating, and remembering an intermediate result while calculating adds switching between storage and processing.
Such tasks also require keeping the current goal active and directing attention to relevant information. Working-memory demand rises as maintenance is combined with reordering, updating, simultaneous processing, and attention control.
Baddeley's multicomponent model places short-term retention of verbal and visuospatial information within a broader working-memory system. Cowan's model explains working memory through temporarily activated memory and attention. Although the models differ, neither treats short-term and working memory as wholly independent abilities.
Simple and complex span tasks place different demands on memory
Span tasks measure how many items can be retained and reproduced briefly. The central distinction is whether another processing task occurs during retention.
| Task format | What the person does | Examples |
|---|---|---|
| Simple span | Retain digits, words, or locations and reproduce them in order | Digit span, word span, location span |
| Complex span | Retain one set of items while alternating with another task | Operation span, reading span |
Digit Span Forward emphasizes short-term retention because the digits are repeated in the same order. Digits Backward adds reversal and therefore greater working-memory demand. It is not identical to a complex span task because a separate processing task is not alternated during retention.
BrainTypeIQ uses Computation Span and Visual Reversal to calculate Gwm. Both add processing beyond holding information unchanged.
In daily life, separate losing information from losing it during processing
If a spoken number disappears before it can be entered, the main demand is temporary retention. If an instruction can be repeated but its order or intermediate results are lost once work begins, the difficulty lies in using the retained information.
Reading requires an earlier subject or condition to be retained and connected with later text. Fluid reasoning requires conditions and intermediate conclusions to remain available while relationships are compared. These situations depend not only on how much can be remembered, but on using information while it is retained.
Instead of treating every experience of forgetfulness as the same, distinguish whether information disappears before use or breaks down while being reordered, updated, or processed. Working memory explains the full ability, and what lower working memory looks like covers its practical effects and adjustments.