https://www.psytoolkit.org/experiment-library/experiment_mul... for the actual runnable experiment. Shared my results below (I'm pretty tired at the moment so don't feel my sharpest)— super curious what others got.
I've been trying to eliminate multi-tasking as much as I can, but the nature of startups day-to-day and even what seems like a single/monotask when zoomed out now often involves context switching (For say, investigating and fixing a user-reported bug, I might have to toggle between VSCode, localhost in browser + the DOM inspector or console, our bug tracker, our support ticketing tool, Slack, and sometimes the Cody window in VS Code/ChatGPT/Claude:
RT in pure trials: 448ms
RT in mixed trials: 710ms
Mixing cost: 262ms
RT in task-repeat trials (in mixed blocks): 710ms
RT in task-switching trials (in mixed blocks): 975ms
Task-switch cost: 265ms
First time:
RT in pure trials: 490ms
RT in mixed trials: 825ms
Mixing cost: 335ms
RT in task-repeat trials (in mixed blocks): 825ms
RT in task-switching trials (in mixed blocks): 969ms
Task-switch cost: 144ms
Second time (while listening to music --- I decided to do this since I've noticed it somehow decreases my latency in typing tests significantly): RT in pure trials: 436ms
RT in mixed trials: 673ms
Mixing cost: 237ms
RT in task-repeat trials (in mixed blocks): 673ms
RT in task-switching trials (in mixed blocks): 746ms
Task-switch cost: 73ms
Edit: third time, also while listening to music: RT in pure trials: 435ms
RT in mixed trials: 608ms
Mixing cost: 173ms
RT in task-repeat trials (in mixed blocks): 608ms
RT in task-switching trials (in mixed blocks): 700ms
Task-switch cost: 92ms
I suspect this "game" is also amenable to practice, and find it at least a bit weirdly addictive in the same way as Flappy Bird.Fascinating that you're measuring milliseconds where I'm having context switches that cost me minutes to hours to days.
I don't think this game is all that representative of context-switching overhead, as my 4th attempt gives evidence that this improves quickly with practice:
RT in pure trials: 422ms
RT in mixed trials: 611ms
Mixing cost: 189ms
RT in task-repeat trials (in mixed blocks): 611ms
RT in task-switching trials (in mixed blocks): 602ms
Task-switch cost: -9ms
The "mixed trials" are naturally slower because I'm having to recognise 4 patterns instead of 2, but only by ~50%.It's so interesting to be able to run the experiment and see for one-self, especially if it's really a matter of 10-15min.
It should be noted that research in this domain is usually done with multi-sensory tasks (e.g https://pubmed.ncbi.nlm.nih.gov/31277054/), and not same channel input like this experiment. It better balances the cognitive load and it's also more realistic, as most people multi-tasking will be using different resources, for instance filling a form while on the phone, or sitting a team meeting while releasing in production.
> For example, no matter how deeply you concentrate on doing a task, if you hear someone shout "fire", you will process that information and act on it.
Not necessarily with Dissociative Identity Disorder! (Or dissociative disorders in general)
Very interesting. I will take some time tonight to run the demo. I am a big believer in not switching tasks if it can be avoided. I loved Cal Newport's book "A World Without Email" which discusses context switching in the 'information worker' space as something that brings productivity to a halt. I believe he is right.