American Journal of Psychology and Behavioral Sciences 2015; 2(2): 33-40 Published online March 10, 2015 (http://www.openscienceonline.com/journal/ajpbs) A Review of Computational Classical Conditioning Models Mehmet Emin Tagluk 1 , Omer Faruk Ertugrul 2, * 1 Department of Electrical and Electronic Engineering, Inonu University, Malatya, Turkey 2 Department of Electrical and Electronic Engineering, Batman University, Batman, Turkey Email address mehmet.tagluk@inonu.edu.tr (M. E. Tagluk), omerfarukertugrul@gmail.com (O. F. Ertugrul) To cite this article Mehmet Emin Tagluk, Omer Faruk Ertugrul. A Review of Computational Classical Conditioning Models. American Journal of Psychology and Behavioral Sciences. Vol. 2, No. 2, 2015, pp. 33-40. Abstract Classical conditioning (CC), which is a basic learning phenomenon, used to explain basic emotions, such as fear, phobia, and reflexes. It was introduced by Pavlov in 1927, and since then it has been investigated in psychological, behavioral, memory, neuroscience, and neurobiology perspectives. It has been used for investigating consumer behavior, conditional fear acquisition and extinction, response extinction and robotic control. Additionally, a large number of methods were proposed to model the CC learning stage. Unfortunately, none of them could model all outcomes of CC. In this study, these computational models, their usages and also the papers about their comparisons are reviewed. It obvious from this review that there is a high requirement to a model, which has a capability to model each feature of CC. Keywords Classical Conditioning, Pavlov, Computational Model, Behavioral Learning 1. Introduction The classical conditioning (CC) is at the heart of our understanding of human learning. CC, which was first demonstrated experimentally by Pavlov in 1927 [1] named as a conditioned reflex, is based on the association of two stimuli; a stimulus (S), which evokes either no or a weak response, usually unrelated to the response that eventually will be learned, and an unconditioned stimulus (US), which consistent a response called the unconditioned response (UR) [2]. In CC, a temporal association between S and US is learned [4] by presenting the S before the US. After a successful conditioning, a specific response R will be observed whatever the presence or absence of the US [5] and the probability to observe and the strength of CR increases over multiple training sessions [2], i.e. can be defined as been strengthening the associative link [6]. Finally, an association is formed between S and US as a result of the time series pairing (S, US) and S is termed as CS, anymore. Similarly, this association can be weaker while having CS with non-occurrence of the expected US followed for a long time [7]. Additionally, behavioral learning theories, in which learning is defined as a change in behavior that occurs as a result of experience, are based on findings about CC. The major outcome of CC is about the main knowledge about human. According to Descartes and the most of other thinkers in the past several centuries, the human body is a marvelous machine and all of its functions or properties are unknown. Therefore they only interested in mind. On the other hand, Pavlov [1] showed that body is a living machine not only a machine or robot, which being touched in the world, by experiments, and this is similar to Aristotle view. For example, Miguez et al. reviewed the results of stress, and they showed that it can produce conditioned analgesia or conditioned hyperalgesia, which can be explained by CC [8], Lindquist et al. investigates the effect of ethanol in CC delay time by using the results of experiments on rats [9] and Dalla and Shors and Brom et al. reviewed the sex differences in learning processes [10, 11]. These examples showed that, the human body is a living machine and his learning is also depending on the physical properties of him. CC is dealing with learned reflex; therefore it becomes a very important issue to understand human or animal behavior, to control behaviors or emotions of them. Classical conditioning can be seen as a basic learning scheme; the learning experiments are sometimes done by human subject [12, 13, 14], but, generally with animals [13, 15, 16, 17, 18,