Behavioral analysis
Performance on the task was defined as the percentage of trials with
correct responses in each phase BEFORE and AFTER the manipulation.
The word pairs presented in the second session of learning did not duplicate
those presented before the manipulation; therefore, any gains
in performance reflect more efficient learning of the new word associations
and cannot be attributed to memory of the associations from the
previous session. To test the effect of the motivational manipulation
on performance, we examined within-subject changes in test accuracy
(BEFORE vs AFTER) and learning phase 2 accuracy (BEFORE vs AFTER),
using paired two-tailed t-tests. In addition, to explore individual differences
in the effects of changing motivation on task performance,
difference scores were calculated by subtracting the percent correct
BEFORE the manipulation from the percent correct AFTER the manipulation
for the learning phase 2 and test phases. We were particularly interested
in the relationship between increasing task motivation and
task performance, so we conducted bivariate correlations between the
motivation change rating from the post-experiment manipulation
check and the performance difference scores from learning phase 2 and
the test phase.