Conditional Relations by Monkeys: Reflexivity, Symmetry, and Transitivity

Abstract

Two cynomolgous macaques categorized six colors into two groups of three after conditional discrimination training (zero-delay symbolic match-to-sample). The procedures resulted in the establishment of relations among the elements of each set-relations that were not specifically trained and that can be characterized by the properties of reflexivity, symmetry, and transitivity. Each set of colors was related to a characteristic pattern of responding: One response pattern involved temporal duration (press and hold the response keys); the second response pattern entailed repeated pressing and releasing of the response keys (fixed ratio 8). Six combinations of two colors were trained, three combinations from each set. After discriminative performance stabilized for each monkey, they were tested with 10 additional color combinations, all of which differed from the training combinations. The conditional relations established between test combinations can be characterized as stimulus equivalence. The training procedures were analogous to the procedure of using category names, and have implications for understanding the function of language in the formation of equivalence classes.

Overcoming response bias using symbolic representations of number by chimpanzees (Pan troglodytes)

“…Consequently, symbols may not be expected to invariably show equivalence relationships with their referents (Cerutti & Rumbaugh, 1993;D' Amato, Salmon, Loukas, & Tomie, 1985;Mcintire, Cleary, & Thompson;Sidman & Tailby, 1982). Although equivalence relationships can develop between stimuli and associated reinforcers (see, e.g., Dube, McIlvane, Mackay, & Stoddard, 1987), the present animals had extensive experience and training with Arabic numerals in multiple contexts, and the numerical stimuli were not consistently associated with any specific reinforcer.…”

Symmetry Versus Sequentiality Related to Prior Training, Sequential Dependency of Stimuli, and Verbal Labeling

“…Extensive attempts have been made to identify varieties of potentially mediating responses in the emergence of stimulus equivalence (e.g., Bentall, Dickens, & Fox, 1993;Bentall & Lowe, 1987, Dickins, Bentall, & Smith;1993;Dugdale & Lowe, 1990;Horne & Lowe, 1996;Mcintire, Cleary, & Thompson, 1987). Although naming or some other kinds of differential responding have been shown to facilitate the emergence of equivalence (Eikeseth & Smith, 1992), there is still no conclusive evidence as to whether conditional discrimination requires differential responding to the conditional stimulus (e.g., Dickins et aI., 1993), and some studies even seem to contradict it (Schusterman & Kastak, 1993;Sidman et aI., 1986).…”

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

“…In other words, if the trained response serves as the common link among the stimuli in a set, there is no need to posit emergent relations to account for test results. Research reported by McIntire, Cleary, and Thompson (1987) demonstrates this problem. McIntire et al trained monkeys, for example, to respond to sample AI in one way (Type I) and to respond to sample A2 in another way (Type 2) to produce comparisons Bland B2.…”