“…Nevertheless, learning is so rapid in the mobile conjugate reinforcement paradigm, particularly in older infants, that this latter comparison must be suggestive only. It is interesting to note, however, that children trained in verbal discrimination tasks consistently demonstrate better recall of S + than S~ (e.g., Deichmann, Speltz, & Kausler, 1971;Goulet & Hoyer, 1969;Rees & Babbitt, 1972).…”