Place avoidance learning and memory in a jumping spider

Abstract

Using a conditioned passive place avoidance paradigm, we investigated the relative importance of three experimental parameters on learning and memory in a salticid, Servaea incana. Spiders encountered an aversive electric shock stimulus paired with one side of a two-sided arena. Our three parameters were the ecological relevance of the visual stimulus, the time interval between trials and the time interval before test. We paired electric shock with either a black or white visual stimulus, as prior studies in our laboratory have demonstrated that S. incana prefer dark 'safe' regions to light ones. We additionally evaluated the influence of two temporal features (time interval between trials and time interval before test) on learning and memory. Spiders exposed to the shock stimulus learned to associate shock with the visual background cue, but the extent to which they did so was dependent on which visual stimulus was present and the time interval between trials. Spiders trained with a long interval between trials (24h) maintained performance throughout training, whereas spiders trained with a short interval (10min) maintained performance only when the safe side was black. When the safe side was white, performance worsened steadily over time. There was no difference between spiders tested after a short (10min) or long (24h) interval before test. These results suggest that the ecological relevance of the stimuli used and the duration of the interval between trials can influence learning and memory in jumping spiders.