Go/No-go task

Introduction

In many experiment paradigms, people’s response speed and accuracy is measured. In some paradigms people’s capacity not to respond is tested. One of these paradigms is known as Go/No-go paradigms (see also Go/No-go on wikipedia). Typically, in some conditions participants have to respond, while in other conditions they are asked not to respond.

The Go/No-go task is great for measuring impulsiveness.

No-go conditions can be combined with many other paradigms, such as flanker and search tasks. For example, visual search paradigms, people only press a button when they find a target, and withhold when they do not find a target.

In another type of a Go/No-go paradigm, people are first asked to respond, but on some trials the go signal changes into a stop signal when you are just ready to respond. See the Stop Signal Task.

About this implementation

In this version, you just see the text Go or No go. When you see Go, you need to respond within 2 seconds. When you see No-go, you need to make sure you do not press the button (for 2 seconds).

This task is made a bit more difficult because there are more Go than No-go trials. You will see that when Go trials repeat, you get faster. But then, when a No-Go trial comes, you might not be able to stop.

Run the demo

In this example, you will

Click here to run a demo

Data output file

In PsyToolkit, the data output file is simply a textfile. The save line of the PsyToolkit experiment script determines what is being saved in the data output file. Typically, for each experimental trial, you would have exactly one line in your text file, and each number/word on that line gives you the information you need for your data analysis, such as the condition, response speed, and whether an error was made.

Meaning of the columns in the output datafile. You need this information for your data analysis.

Colum	Meaning
1	Name of task: go or nogo
2	The response speed (in nogo trials, this is 2000, the timeout)
3	The error status (0 is correct, 1 is error)

PsyToolkit code

Click to expand the PsyToolkit script code (part of zip file below)

bitmaps
  instructions
  gosignal
  nogosignal
  errortype1
  errortype2

task go
  keys space
  set $errorstatus 0
  show bitmap gosignal
  readkey 1 2000 # wait 2 seconds for key to be pressed
  clear 1
  if STATUS == TIMEOUT
    set $errorstatus 1
    show bitmap errortype2
    delay 2000
    clear 2
  fi    
  delay 500 # intertrial interval
  save TASKNAME RT $errorstatus 

task nogo
  keys space
  set $errorstatus 0
  show bitmap nogosignal
  readkey 1 2000
  clear 1
  if STATUS != TIMEOUT  ## there should be a TIME OUT, so if not, we have a mistake
    set $errorstatus 1
    show bitmap errortype1
    delay 2000
    clear 2
  fi    
  delay 500 # intertrial interval
  save TASKNAME RT $errorstatus 

# -------------------------------------

message instructions

block test
  tasklist
    go 20
    nogo 5
  end

Download

The PsyToolkit code zip file

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Go/No-go task

Introduction

About this implementation

Run the demo

Data output file

PsyToolkit code

Download

Further reading