# Check a key released

**URL:** <https://psychtoolbox.discourse.group/t/check-a-key-released/1704>\
**Category:** Uncategorized\
**Created:** [October 2, 2006, 3:47pm UTC](https://psychtoolbox.discourse.group/t/check-a-key-released/1704 "2006-10-02T15:47:20Z")\
**Posts on this page:** 2\
**Page:** 1

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**Author:** ![sebastien\_crouzet](https://avatars.discourse-cdn.com/v4/letter/s/43a26b/32.png) [@sebastien\_crouzet](https://psychtoolbox.discourse.group/u/sebastien_crouzet)\
**Post date:** [October 2, 2006, 3:47pm UTC](https://psychtoolbox.discourse.group/t/check-a-key-released/1704/1 "2006-10-02T15:47:20Z")

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Hi,  
  
I run actually an experiment with PTB 2.54 on windows.  
I want to display a stimulus and check for response of the subject  
(this is done without problems). The problem is that i want the  
subject to keep his 2 index on each ctrl button of the keyboard, and  
released one if the stimulus is the target, the other if the stimulus  
is a distractor.  
  
My experiment run perfectly if a check for key\_pressed, but i have  
absolutly no idea of the method to check for key\_released... It seems  
that KbCheck have not been made for this and i'm afraid i can't do  
what i want...  
  
I hope that someone have already be in front of this problem.  
I specify that i need acurate timing so it's better if i don't use  
GetChar.  
  
Thanks  
sebastien

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**Author:** ![lsolomyak](https://avatars.discourse-cdn.com/v4/letter/l/85f322/32.png) [@lsolomyak](https://psychtoolbox.discourse.group/u/lsolomyak)\
**Post date:** [February 9, 2021, 4:40pm UTC](https://psychtoolbox.discourse.group/t/check-a-key-released/1704/2 "2021-02-09T16:40:34Z")

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Hi sebastian, i am struggling with the same problem. Did you find any good solutions?