Label	Description	Common alternative labels
Stop-signal task	A task used to measure response inhibition in the lab. Consists of a go component (e.g. a two-choice discrimination task) and a stop component (suppressing the response when an extra signal appears).	Stop-signal reaction time task, stop-signal paradigm, countermanding task
Go trial	On these trials (usually the majority), participants respond to the go stimulus as quickly and accurately as possible (e.g. left arrow = left key, right arrow = right key).	No-signal trial, no-stop-signal trial
Stop trial	On these trials (usually the minority), an extra signal is presented after a variable delay, instructing participants to stop their response to the go stimulus.	Stop-signal trial, signal trial
Successful stop trial	On these stop trials, the participants successfully stopped (inhibited) their go response.	Stop-success trial, signal-inhibit trial, canceled trial
Unsuccessful stop trial	On these stop trials, the participants could not inhibit their go response; hence, they responded despite the (stop-signal) instruction not to do so.	Stop-failure trial, signal-respond trial, noncanceled trial, stop error
Go omission	Go trials without a go response.	Go-omission error, misses, missed responses
Choice errors on go trials	Incorrect response on a go trial (e.g. the go stimulus required a left response but a right response was executed).	(Go) errors, incorrect (go or no-signal) trials
Premature response on a go trial	A response executed before the presentation of the go stimulus on a go trial. This can happen when go-stimulus presentation is highly predictable in time (and stimulus identity is not relevant to the go task; e.g. in a simple detection task) or when participants are ‘impulsive’. Note that response latencies will be negative on such trials.
p(respond|signal)	Probability of responding on a stop trial. Non-parametric estimation methods (Materials and Methods) use p(respond|signal) to determine SSRT.	P(respond), response rate, p(inhibit)=1 p(respond|signal)
Choice errors on unsuccessful stop trials	Unsuccessful stop trials on which the incorrect go response was executed (e.g. the go stimulus required a left response but a right response was executed).	Incorrect signal-respond trials
Premature responses on unsuccessful stop trials	This is a special case of unsuccessful stop trials, referring to go responses executed after the presentation of the go stimulus but before the presentation of the stop signal. In some studies, this label is also used for go responses executed before the presentation of the go stimulus on stop trials (see description premature responses on go trials).	Premature signal-respond
Trigger failures on stop trials	Failures to launch the stop process or ‘runner’ on stop trials (see Box 2 for further discussion).
Reaction time (RT) on go trials	How long does it take to respond to the stimulus on go trials? This corresponds to the finishing time of the go runner in the independent race model.	Go RT, go latency, no-signal RT
Stop-signal delay (SSD)	The delay between the presentation of the go stimulus and the stop signal	Stimulus-onset asynchrony (SOA)
Stop-signal reaction time (SSRT)	How long does it take to stop a response? SSD + SSRT correspond to the finishing time of the stop runner in the independent race model.	Stop latency
RT on unsuccessful stop trials	Reaction time of the go response on unsuccessful stop trials	Signal-respond RT, SR-RT (note that this abbreviation is highly similar to the abbreviation for stop-signal reaction time, which can cause confusion)
Note: The different types of unsuccessful stop trials (including choice errors and premature responses) are usually collapsed when calculating p(respond|signal), estimating SSRT, or tracking SSD.