Fig. 2.

Illustration of the cues and outcome in Kamin (1969) blocking paradigm (a). During randomized training the weight from the more frequent light cue to the outcome food is increased until light completely predicts food by itself (b). This effect is amplified when the light is trained first by itself to predict food (c). While in b) the tone can temporarily increase its weight, it almost can’t increase its weight in c). When the compound cue consisting of light and tone is trained first (d), the weight of the tone cue stays constant (until a new training regimen, e.g. as in b) would be applied)