Key points are not available for this paper at this time.
Kathryn Kernodle Loveland, J. Gregory Olley, The Effect of External Reward on Interest and Quality of Task Performance in Children of High and Low Intrinsic Motivation, Child Development, Vol. 50, No. 4 (Dec., 1979), pp. 1207-1210
Loveland et al. (Sat,) studied this question.