Many everyday situations require you to withhold or change an action that has already started. Laboratory tasks such as the Flanker and Stop-Signal tests are designed to study this kind of control.
1. Two kinds of conflict
Interference tasks put pressure on your response system in different ways:
- Distractor conflict – irrelevant stimuli push you towards the wrong response (Flanker).
- Stop conflict – a late signal tells you to cancel a response that is already underway (Stop-Signal).
2. Flanker: ignoring misleading neighbours
In the Flanker task you respond to a central arrow and ignore arrows on each side. When the flankers point the opposite way, reaction times increase and errors become more likely.
This reflects how well your attention system can lock onto the central target while inhibition suppresses the pull from the neighbours.
3. Stop-Signal: braking an action in progress
In the Stop-Signal task you normally respond quickly to a “go” signal. On some trials, a second signal appears shortly afterwards telling you to stop.
By adjusting the delay between the go and stop signals, researchers can estimate how fast your internal “brake” can cancel an ongoing response.
4. Everyday relevance
Similar demands appear when you:
- Hit the brakes after a hazard appears while driving.
- Stop yourself from pressing “send” on a message written in anger.
- Abort a move in a game when the situation suddenly changes.
In all these cases, the system that initiates actions must cooperate with a system that can interrupt them when needed.
5. Using Flanker and Stop-Signal tasks sensibly
Our online versions of the Flanker and Stop-Signal tests can give you a feel for how your inhibition behaves under controlled conditions.
They are not driving tests, clinical assessments or safety certifications. Instead, they are tools to explore patterns: for example how sleep, stress or distraction change your ability to handle conflicting signals.
These tasks and this article are for educational use only. They do not diagnose any condition or measure whether you are “safe” for driving, work or other activities. If you have concerns about your self-control or reaction to unexpected events, talk to a qualified professional.