Press the Button Except When the Letter is X (image) Norwegian University of Science and Technology Share Print E-Mail Caption Study participants were told to press a button when they saw a letter in their video goggles, except when the letter was X. This task enabled researchers to see which parts of the participants' brains were engaged when they did the task. Credit llustration courtesy Alexander Olsen/NeuroImage Usage Restrictions With proper credit and only in association with stories about this research. Share Print E-Mail Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.