Glossary · 4 · Instructions and action
Resumption lag
Also known as: Interruption resumption lag
In interruption research, the resumption lag is the time between the end of an interruption and the first action of the resumed primary task, during which people retrieve the suspended goal and their place in the task; it is often accompanied by errors such as repeating or skipping a step.
- Applied cognitive psychology
- Instructions and action
In one sentence
Resumption lag is the time needed to pick up an interrupted task again, often with skipped or repeated steps (Altmann and Trafton; Trafton et al., 2003).
Example
A technician is called away in the middle of a twelve-step filter change. Because each step ends with a visible result and the steps are numbered, she sees on return that step 7 is done and step 8 is next, instead of guessing.
Rests on
- Prospective memory and Working memory: in the memory-for-goals model of Altmann and Trafton, a suspended goal decays and must be retrieved; cues in the environment prime the retrieval.
- Slips, lapses and mistakes: omissions and repetitions after interruptions are typical lapses.
How it applies
- Re-entry points: Numbered steps, one action per step and a visible result after each step let readers see where they stopped.
- Check before continuing: In long procedures, insert steps that confirm the state ("Check that the pressure gauge shows 0 bar before you continue").
- Restart after a stop: Procedures for restarting a machine or line after a stop state what to check first, because the operator's picture of the situation may be outdated.
- Software documentation: Wizards and long configuration procedures show progress and allow a saved state to be resumed.
- Cues: Trafton and colleagues found that resumption is faster when people can prepare before the interruption and when cues of the task state remain visible.
Limits
- Most findings come from laboratory tasks with controlled interruptions; real interruptions vary in length and demand.
- Documentation can reduce the effect of interruptions but not prevent them; safety-related steps must not depend on the reader remembering where they stopped.