Responses to operant conditioning in the corn snake, Pantherophis guttatus, using olfactory and visual stimuli

Snakes are historically underrepresented in experimental studies of learning. Operant conditioning reinforced by food rewards has successfully been applied to a few species, and corn snakes have learned to use visual cues to locate a hiding spot, but despite the growing popularity of snakes as pets, their capacity for learning is largely unexplored. We used reinforcement with food rewards to train two cohorts of corn snakes ( Pantherophis guttatus , 15 snakes in total), on olfactory and visual cues in two separate experiments. We applied a criterion for acquisition of at least 7 correct decisions in any 8 consecutive trials, and for the first cohort tested for reversal learning of olfactory and then visual cues once the criterion was met. Error rates and latencies to correct choices declined significantly in cohort 1, a group of eight three-year-old snakes. The response of a second cohort of seven three-year-olds was more subtle: all but one reached criteria, but with no overall decline in error rates. When subjected to repeated reversals, in which the identity of the reinforced cue was switched, cohort 1 responded increasingly quickly to each successive reversal, demonstrating the cognitive abilities to inhibit learned responses and to switch their attention to the previously irrelevant cue. Corn snakes show promise as a representative species for learning in reptiles.