Within this component you will find: 1. The decision task files for a German and an English version. The decision task was made with the help of jsPsych library (de Leeuw, J. R. , 2015; https://www.jspsych.org). To run the task, launch either the "studie-ya-eng.html" file in the "study_eng" folder for the English version, or the "studie-ya.html" file for the German version in the "study" folder. The task is meant to be hosted on a server and the results would then be saved on the server as CSV files. Even though the task itself can run locally on a computer, to save the results without running the task on a server, a local server is required (a detailed description is available at https://www.jspsych.org/overview/data/). XAMPP software (https://www.apachefriends.org/index.html) can be used to run a local server. Decision task files can then be unpacked from the zip archive and put into the htdocs folder of the XAMPP location. Task can be started by typing "localhost/study_eng/studie-ya-eng.html" in the address bar of a web browser. The decision grid task files already include the short PHP code required for saving CSV result files. Images used in the decision grid task are saved in the folder "img" in the task folder. The task expects the input of ages in years within the age ranges of recruited participants (18-30 for younger adults and 65-80 for older adults). 2. English and German instructions saved as PDF files "Instructions - Positivity Effect and Decision Making in Ageing - English.pdf" and "Instructions - Positivity Effect and Decision Making in Ageing - German.pdf". They include screenshots of all trials of the behavioral task with all instruction screens and messages that are presented to participants.