OS error: Couldn't find image check path: Go-nogo experiment

OS: Win10
PsychoPy version: 3.2.4

What are you trying to achieve?:
I am designing a go-nogo task. The following error always crops up, and I am not sure why. I have checked the file names and everything but I am not able to find the error.

This is the excel file:

Could you please help me check where is the problem, the excel file or there is some other issue. Thank you.


do want to run the experiment online. If so, it is best advice to use only “/” instead of “”. Does psychopy look in the proper folder for the stimuli? It looks as if you have a Go_Nogo folder in your Go_Nogo folder. I suggest to use more a informative name such as stimuli to facilitate debugging.

Bets Jens

I would eventually shift this experiment to online mode only. I am also not sure why psychopy is going to another folder name Go_Nogo. I also tried to shift the whole folder to the desktop and also change the name of the folder. But still, the same error is showing.

I tried to change the name in the excel file, but it didn’t work.

I also checked the code in the compiler. There the path was fine.

thisExp = data.ExperimentHandler(name=expName, version='',
    extraInfo=expInfo, runtimeInfo=None,
    savePickle=True, saveWideText=True,
# save a log file for detail verbose info
logFile = logging.LogFile(filename+'.log', level=logging.EXP)
logging.console.setLevel(logging.WARNING)  # this outputs to the screen, not a file

This part of the code is where I think the images are called

# set up handler to look after randomisation of conditions etc
UP_DOWN = data.TrialHandler(nReps=1, method='sequential', 
    extraInfo=expInfo, originPath=-1,
    seed=None, name='UP_DOWN')
thisExp.addLoop(UP_DOWN)  # add the loop to the experiment
thisUP_DOWN = UP_DOWN.trialList[0]  # so we can initialise stimuli with some values
# abbreviate parameter names if possible (e.g. rgb = thisUP_DOWN.rgb)

I hope this much information may help to look for the problem.


you mind uploading the experiment *.psyexp along with the excel-file and some pictures or giving access to your gitlab-project? It does not have to be the whole experiment.

Best Jens

Sure, I will upload my experiment here.
Go-Nogo.psyexp (29.0 KB)
GNG_prac_list.xlsx (9.1 KB)
triangle_down triangle_left triangle_right triangle_up

I hope this helps in looking for the solution.


please find attached my psychopy-code. This loads your stimuli from a folder called stim which resides in a folder GoNoGo.

GNG_prac_list.xlsx (9.2 KB) Go-Nogo.psyexp (29.1 KB)

Notice that I had to make a couple of change to your code to make it running on my computer. But then it loaded the stimuli without any problem.

jitter = [0.5,0.6,0.7,0.8,0.9,1]
  1. I had to change the polygon to a text stimuli.

  2. It might be helpful to save the duration/jitter

thisExp.addData('jitter', jitter)

To do so insert the code mentioned above in the End Routine tab of your code-element.

Best Jens

Thanks for your help throughout. But still, my experiment is not working. This time a different error is coming up.

Traceback (most recent call last):
  File "F:\GNG\Go-Nogo_lastrun.py", line 537, in <module>
  File "C:\Program Files\PsychoPy3\lib\site-packages\psychopy\visual\window.py", line 910, in flip
  File "C:\Program Files\PsychoPy3\lib\site-packages\psychopy\visual\text.py", line 775, in draw
    self.rgb, self.colorSpace, self.contrast)
  File "C:\Program Files\PsychoPy3\lib\site-packages\psychopy\visual\basevisual.py", line 439, in _getDesiredRGB
    rgb = rgb / 127.5 - 1
TypeError: unsupported operand type(s) for /: 'NoneType' and 'float'

Can you tell me why this error might be showing.


I do not speak JavaScript. I have to rely on PsychoPy’s autotranslate and google-searches but what do you compute here:


Best Jens

Actually, I also have no clue what this is calculating. I haven’t added anything like this in my experiment. The experiment is the same as I have provided earlier in this thread.


do you set the colour of a stimulus somewhere?

Best Jens


did you try to adopt my example to your needs? As you might have noticed, I had to make some changes to your program to get it running, for instance I replaced the polygon with a text-stimulus (+).

Best Jens