**Go/NoGo Response Inhibition Task** The Go/NoGo task is designed to measure response inhibition. In the average Go/NoGo task there are 2 conditions. In the Go-condition there is no response inhibition element. The participant needs to react to every stimulus that is presented. In the Go/NoGo-condition sometimes a response is needed and sometimes no response is needed (response inhibition). In general the response time differs between the Go-condition and the Go/NoGo-condition. Participants are in general faster in the Go-condition than in the Go/NoGo-condition. This is useful in experimental or clinical settings. **Differences and Similiarities** The task is a copy of the Go/NoGo Response Inhibtion Task as described in Menon et al. (2001). However to make the task suitable for use in the Open Sesame environment a few adjustments are made. The experiment as described by Menon et al. (2001) consists of a Go-condition and a Go/NoGo-condition. In both conditions participants viewed a series of letters. Which letters are presented in the experiment of Menon et al. (2001) remains unclear. The letters that are chosen to be used in this task for the Go-condition are the first letters of a QWERTY-keyboard (QWERTYUIOP etc.) The letters that are chosen to be used in this task for the Go/NoGo-condition are the W, R, Y, I, P, S, F, H, K, etc. which is every second letter on the QWERTY-keyboard. In the experiment of Menon et al. (2001) it remains unclear if participants start with the Go-condition or with the Go/NoGo-condition. So the start of the experiment is counterbalenced. This means that when the participant has an even subject number they start with the Go/NoGo-condition. When the participant has an uneven subject number they start with the Go-condition. Also a practice phase is added to get participants familiar with the task. After the practice phase, the participant starts with the actual task. Depending on the subject number of the participant the start is either in the Go-condition or in the Go/NoGo-condition. In the Go-condition the participant has to respond to every letter that appears on the screen. In the Go/NoGo-condition the participant has to respond to every letter that appears on the screen except for the letter 'X'. Every condition takes 26 seconds to complete. After 26 seconds the participant is informed about which condition comes next by a instruction screen which lasts 2 seconds. The experiment as described by Menon et al. (2001) consist of an 30-seconds rest epoch to start with and of epochs of 26-seconds (one condition). After one condition is finished the participant goes to the other condition which also lasts 26-seconds. In total the participant will switch 12 times of condition. How many times a participant goes through a whole cycle of switching 12 times between the conditions remains unclear in Menon et al. (2001). To change the number of times a letter is presented in a condition. The option 'repeat cycle' should be changed. When the 'repeat cycle' option is changed in the loop-item, pay attention to the summary. This will indicate how many times the items in the loop will be executed. The same principle applies for other loop-items. This means that the experimenter can change the length of the task. **Data-File** After the experiment is finished Open Sesame will create a log file. This file contains all the variables of the task. The Text Import Wizard can convert the logfile into a readable Excel file. In order to get the conversion done the following options should be chosen: - Delimited - My data has headers - Delimiters: Comma - Start Import at row: 1 In order to compute for example Reaction Time or Correct Response as is done by Menon et al. (2001). The following variables can be used to make that computation: - *response* - *response_KBR_Control* - *response_KBR_Experimental* - *response_time* - *response_time_KBR_Control* - *response_time_KBR_Experimental* The variable *respons* is the response given by the participant. The variable *response_KBR_Control* is the correct response in the Go-condition or Control-condition. When the participant is in the Go/NoGo-condition or Experimental condition then "None" will be shown in the list of the *response_KBR_Control*. For the variabale *response_KBR_Experimental* the same principle applies. This is the correct response in the Go/NoGo condition or Experimental Condition. When the participant is in the Go-condition "None" will be shown in the list of the Go/NoGo-condition. This can be quite confusing because when participants withhold their response "None" is also shown. In order to find out in which condition the participant was, take a look at the response time. The variable *response_time* is the response time per letter. When the participant switches to the other condition, the response will be "None". The *response_time* for either *response_time_KBR_Control* or *response_time_KBR_Experimental* will stay the same for a couple of letters (when the participant is in the other condition). In order to compute if the reponse time is higher in the Go/NoGo condition than in the Go-condition. First, extract only the correct trials. Second, create new variables in which the response time is given for both the variables. Than substract the Go-condition response times of the Go/NoGo-condition response times. This will lead to a measure for response inhibition. **References** Menon, V., Adleman, N. E., White, C. D., Glover, G. H., & Reiss, A. L. (2001). *Error‐related brain activation during a Go/NoGo response inhibition task*. Human brain mapping, 12(3), 131-143. **Additional Information** In order to open the experiment you need to install Open Sesame on your computer. http://osdoc.cogsci.nl/3.1/download/ The experiment is build with Open Sesame version 3.1.9 with Python version 2.7. If you have any further questions. You can contact me w.de.vries.22@student.rug.nl