Acquisition of appetitional and palpebral conditioned reflexes by the same infants

The establishment of appetitional and palpebral conditioned reflexes was compared in three groups of 26 infants, 3--150 days old. The age range within each group at the beginning of conditioning was 0--20 days for both methods. The parameters compared were the time to reach equal criteria for the establishment of the conditioned response, and the nature of acquisition. The main results are as follows: (1) appetitional CR was established more quickly than palpebral CR; (2) the relative rates of conditioning in both methods were correlated in the same infants (r = 0.84; P<0.001); (3) the course of conditioning was in striking agreement in infants of the same age, both premature and full-term, for the two applied methods, but different for groups of infants of different ages. The results indicate that two quite different methods yield a picture of differences in the functional capacity of the CNS which are in close agreement with those for age.