The question of bidirectional associations in pigeons’ learning of conditional discrimination tasks

Common coding in pigeons: Partial versus total reversals of one-to-many conditional discriminations

“…However, results from other animal research suggest that pigeons are unable to demonstrate the transitivity relation (D 'Amato, Salmon, Loukas, & Tomie, 1985;Lipkens, Kop, & Matthijs, 1988;Richards, 1988) and that monkeys and baboons (D 'Amato et al, 1985;Sidman et al, 1982) and pigeons (D 'Amato et al, 1985;Hogan & Zentall, 1977;COMMON CODING IN PIGEONS 379 Lipkens et al, 1988) are unable to demonstrate the symmetry relation. If the reasons for these failures with animals could be identified, we might be in a better position to determine the boundary conditions under which stimulus equivalence occurs.…”

“…One problem with some of the designs that have tested for these emergent relations is that they do not allow the animal experience with the test stimuli in locations or under conditions that are similar to the test locations or conditions. For example, in Hogan and Zentall's (1977) test for symmetry, in which pigeons learned to respond to comparison B when the sample was A and were then tested for their response to comparison A when the sample was B, the A samples had never before appeared as comparisons (see also Richards, 1988). Even when animals have experienced the test stimuli in their test locations, symmetry effects may not be found (Lipkens et al, 1988), but as Lipkens et al noted, "equivalence relations can fail to emerge because a stimulus presented separately as a sample can be a different stimulus when presented as a comparison in combination with another comparison even though its spatial location remains the same" (p. 406).…”

Acquired equivalence of cues in pigeon autoshaping: Effects of training with common consequences and with common antecedents

“…Viewed in this way, the backward equivalence effect can be seen as providing one more piece of evidence in favor of the reality of excitatory backward conditioning to be added to those that have recently begun to emerge from studies of discrimination learning in pigeons (e.g., Richards, 1988;.…”

Concept Learning in Animals

“…Certainly, this is true of Pavlovian associations; forward associative training (CS-US) results in a strong conditioned response, whereas backward associative training (US-CS) does not. Furthermore, if following matching training, one interchanges the samples with the comparisons, then little evidence of transfer has been generally been found (Gray, 1966;Hogan & Zentall, 1977;Richards, 1988;Rodewald, 1974;but, see Frank & Wasserman, 2005, for more much encouraging results). However, training the association in both directions might eliminate the directionality of an association.…”