In the studies reported here, we spaced cue-approach training over two
consecutive days to test whether spacing improves the maintenance of a shift in
choice behavior. In the standard cue-approach task, participants are cued to
press a button on the keyboard when a neutral tone is heard at a variable time averaging
750 ms after the food item image appears on the screen. In a subsequent choice
phase, participants choose between two items that were equated for pre-experimental
preferences. Participants are told that they will receive the item they chose
on a randomly selected trial to eat. In this phase, participants tend to choose
items previously associated during training with the tone and button press 3.
To facilitate discussion of methods and results across the three studies
presented here, we define a Spaced item as an item that appeared on both days
of cue-approach training (i.e. half of the training phase presentations were on
day 1 and the second half of the training phase presentations appeared on day
2). We define Massed items as items that were trained on a single day, i.e. all
the training phase presentations appeared on the same day. We define
within-session lag as the average number of intervening other-item trials
between presentations of a particular item on one day.
In the three studies reported here, we tested the effect that spacing cue-approach
training over two consecutive days had on choice behavior after one week and one
month. Additionally, we tested the effect of the order in which Massed items
appeared: either on the first or second training day. Finally, we tested how the
length of within-session lag during training influenced the choice effect.