After exclusion, participants were randomly assigned to one of three conditions: the selfie with "likes" condition, the selfie only condition (view a “selfie” with no feedback), or the neutral picture (control) condition.

In the selfie with "likes" condition, participants took a pictures of themselves and were shown how to get high exposure on Instagram, and were given time to take and edit a “selfie” on their phones. While they could observe how many likes they received, in reality, a transparent screen developed for the study was opened that generated an increased amount of fake "likes".

In the selfie only condition, participants uploaded a new “selfie” to their Instagram account following the same procedure. However, upon uploading the "selfie,” no feedback nor “likes” were provided.

In the neutral picture condition, participants did not take or upload a “selfie” to Instagram. Instead, these participants observed a picture of gravel on a dummy Instagram account before moving on to the next task. A picture of gravel was used to ensure that participants did not find the experience rewarding or reflect upon the self.

This helped to determine if any effect on P3a (which reflects emotional arousal and is sensitive to psychological distress) are due to the “likes” themselves, or merely viewing a picture of the self.