We have previously shown (Schmajuk, 1997), that the SLG model addresses different basic conditioning paradigms, including (a) simultaneous, delay and trace conditioning, and the effect of varying the interstimulus interval (Smith, 1968); (b) the effect of increasing US duration (Burkhardt & Ayres, 1978); (c) backward conditioning (Siegel & Domjan, 1971; Heith & Rescorla, 1973); (d) second-order excitatory (Kamil, 1969) and inhibitory conditioning (Rescorla, 1976); (e) sensory preconditioning (Brogden, 1939); and (f) partial reinforcement with different percentages of reinforced trials (Gormezano & Moore, 1969). According to the model, interstimulus interval (ISI, see Figure 2.3) effects are explained in terms of the shape of the trace τCS (see Figure 2.3 and Equation [2.1]), the effect of increasing US duration in terms of the increase in the size of the temporal overlap between XCS and λUS (see Equation [2.9a]), backward conditioning in terms of the combination (chaining) of CS–CX and CX–US associations (see Equation [2.3]), second-order conditioning and sensory preconditioning in terms of the combination (chaining) of CS1–CS2 and CS2–US associations. The model correctly describes the competition between the excitation due to chaining and the conditioned inhibition (see below), produced by the alternated presentations of CS–CX (or CS1–CS2) and CX–US (or CS2–US) trials, present in backward conditioning, second-order conditioning and sensory preconditioning.

Recent simulations show that the SLG model also describes the effect of massed vs. spaced trials (e.g. Spence & Norris, 1950) in terms of the increased CX–US associations (that compete with CS–US associations) when massed trials are used.