Operant Conditioning

This weekend, Tiago stunned his parents. What began as a protest to being in the jumper, turned into delight at mommy's obnoxious squealing and abundant applause every-time that he bounced. Although not able to capture his initial "ah-ha" moment on video, daddy was there to see it. The next day, when placed in the jumper, Tiago immediately smiled at mommy and jumped once, paused and waited for mommy's reaction. He was delighted that he could still cause the same response. (This video was taken afterwards and the thrill may have worn off some.) Who is conditioning who remains to be known...