Complex sentence: In some studies they found that high anxiety (high drive) participants would make a greater number of mistakes, therefore taking longer for the participants to reach the learned criterion, where as participants with low anxiety (low drive) would reach the learned criterion quicker.
Split into simpler sentences: In some studies they found that high anxiety (high drive) participants would make a greater number of mistakes, therefore taking longer for the participants to reach the learned criterion. Where as participants with low anxiety (low drive) would reach the learned criterion quicker.