The AlAn's game: description of three trial types.

<p><b>2.A</b>: Matrix with “You Gain” values (Y axis) and “Red Cross Loses” values (X axis) in cents. Each cell in the matrix represents a single offer. <b>AT</b> = active trials; arrow from AT points to a screencapture showing a sample active trial in which “You” will get 2 cents but the Red Cross donation will decrease by 64 cents. Note that the “You” amount varies independently from the “Red Cross” amount. <b>A</b> = Attention-Control; trials in which either a “Yes” results in a loss for both subject and Red Cross (top row of matrix), or a “Yes” results in gain for the subject and no loss for the Red Cross (first column of matrix); arrow from A points to a screencapture showing a sample Attention-Control trial in which “You” will lose 2 cents and the Red Cross donation will decrease by 32 cents. Note: Thicker borders indicate the quadrants for which percentage of “Yes” responses across those 9 Active Trials were calculated (see <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0036158#s2" target="_blank">Materials and Methods</a>, Data Analyses, Between-Group analyses). <b>2.B: C</b> = Calculations, in which subjects decide whether the “You” number is bigger than the Red Cross number; arrow points to a screencapture showing a sample calculation trial in which the “You” number (4 cents) is not bigger than the “Red Cross” number (8 cents).