Associative theory versus classical conditioning: Their proper relationship

Although Turkkan's target article is an interesting attempt to apply classical conditioning to a wide variety of issues, it may also foster the mistakes ofprevious enthusiasts that have allowed classical conditioning to be used as an easily discredited straw man. In particular, Turkkan uses "classical conditioning" and "associative learning" in a largely interchangeable fashion as has been the tendency since the 1920s (e.g., Guthrie 1930; Watson 1925). However, classical conditioning is not a subset ofassociative learning or vice versa. More properly, they should be viewed as separate but overlapping domains of discourse. Associative learnlng. Associative learning is hardly the sole province of classical conditioning. The key principles of associative theory, especially contiguity and similarity, predate Pavlov's research by 100 years in the case ofthe British Associationists and 2,000 years in the case of Aristotle. Moreover, at about the same time as Pavlov's early experiments, the research by Ebbinghaus (1885) in serial learning, Calkins (1894) in paired associate learning, and Thorndike (f898) in instrumental learning were all conducted explicitly in the associative tradition. Much of Turkkan's discfission concerning "language processes" would seem less speculative had it taken into account research in verbal learning and also more recent research concerning associative contributions to cognitive and linguistic processes (e.g., Gluck & Bower 1986; Rumelhart, Hinton & McClelland 1e86). Associative models of crassrca, condltlonlng. Much of the confusion between classical conditioning and associative learning arises from a confusion between classical conditioning as a set of empirical phenomena and the development of associative models based on those phenomena (e.g., Frey & Sears 1978; Mackintosh 1975; Pearce & Hall 1980; Rescorla & Wagner 1972; Sutton & Barto l98l). Despite their origins, these associative models can be applied to phenomena that transcend dven the most widely drawn boundaries of classical conditioning. For example, Rudy (f974) has adapted the Rescorla-Wagner model to paired associate learning. More recently, a key feature ofthe Rescorla-Wagner model, namely, its assumptions about competition among stimuli for associative strength, has been recognized as identical to a learning rule used for tuning adaptive units in parallel distributed processing networks (Sutton & Barto l98f). These network models are being applied to a wide range of perceptual and cognitive phenomena, for example, pattern recognition, rule learning, and language acquisition (see Rumelhart & McClelland f986). Thus, while models arising from classical conditioning may be used to increase the sophistication and domain of associative theory, there is no gain in dragging along the label of "classical conditioning. " Ctassical condittontng. While classical conditioning certainly remains a good instrument for the study of associative processes (Gormezano & Kehoe l98l; Lashley 1916), classical conditioning preparations are being extended to matters well outside the uaditional agenda of associationism. For example, a large number of previously ignored nonassociative reflex phenomena are being better integrated with the study of associative processes, to their mutual benefit, For example, as Turkkan has noted, considerable strides have been made in identifring the synaptic mechanisms for behavioural change in the reflexes of the aplysia through the concerted examination ofhabituation, sensitization, and conditioned reflexes (e.g., Carew et al. 1984; Hawhns & Kandel 1984). At a less molecular level, classical conditioning methods have been used to investigate phenomena more widely studied using verbal and/or instrumental methods, for example, selective attention (e.g., Kamin 1968; C om.mentarylTurkkan: Classical conditioning