We aim to investigate how people discriminate between happy and angry facial expressions.
Participants will have to decide within 2 seconds if the face briefly presented on each trial is angry or happy, by pressing left arrow key for angry and right arrow key for happy.
Then, participants will have to rate within 3 seconds how confident they are in their judgement using a slider from 1 to 100, with indicators Unsure (1), Somewhat sure (34), Fairly sure (67), Very sure(100).
The run consists of 60 trials, with a short break after the first 30 trials, and will take about 5 minutes.
The task is an N-down staircase version. Step sizes: [16%, 8%, 4%, 3%, 2%, 1%, ..., 1%]. It consists of 2 blocks, each starts above or below the threshold, the starting order is randomised in the beginning of the task. Each block consists of 30 trials, the gender of the morphs is interleaved so that the gender presented on each trial is pulled out from a vector of genders with the length of the No. of trials per block. The vector is randomised in the beginning of each block.
To run it on your own computer you will need the .psyexp file and the Stimuli folder. To run it online you will need to create and upload the html folder on Pavlovia.