Abstract

Rodents typically produce rhythmic sets of licks that can be grouped into clusters on the basis of the intervals between licks. The mean number of licks in a cluster (cluster size) is directly related to the concentration of palatable and unpalatable solutions. These relationships suggest that lick cluster size might be a useful index of the intensity of an animal’s (hedonic?) reaction to the solution being consumed. Wagner’s SOP theory is based around the idea that both the level of response to a stimulus, and the amount of learning based on its presentation, depends on the degree to which its representation is activated. Today, I will describe experiments relating to sensory preconditioning, simultaneous contrast, and contrast-based learning (aka US-priming, diminution of the UR and attenuation of CS-US learning) where the analysis of the microstructure of licking has provided novel information beyond that which can be gleaned from the analysis of consumption alone. In each of these three situations SOP either offers novel possible accounts of the data (sensory preconditioning and contrast) or receives novel detailed support from it (contrast learning).