Overtraining and the use of feature and geometric cues for reorientation

Environmental cue difference and training duration modulate spatial learning and cue preference in detour task

In this study, we investigated how different environmental cue and the proficiency of body motion influenced detour learning behaviour and cue preference in cue conflict situations. Domestic chicks were trained to detour around an obstacle and follow a fixed route to rejoin with their partners. When the environmental cue was red vs. blue vertical stripes, the chicks learned the detour task quicker, and as the number of training trials after route acquisition increased, they switched their preference from the environmental cue to a body-motion cue in the cue conflict test. On the other hand, when the environmental cue was vertical vs. horizontal blue stripes, the chicks learned the detour task slower and showed a dependence on the body-motion cue regardless of the number of training trials performed after route acquisition. When the environmental cue was removed, most chicks could still successfully detour according to the specific route on which they had been trained. Furthermore, a significant difference in detour latency was found between chicks using the environmental cue and chicks using the body-motion cue, suggesting separate neuronal circuits responsible for processing the two types of information. Our results demonstrated that young domestic chicks could use both environmental cue and body-motion cues to memorize the route during the detour learning task; however the detour route preference could be dynamically modulated by difference of the environmental cue and the number of training trials they received. Illustrated Abstract Young domestic chicks could use environmental cues and body-motion cues to memorize route in a detour learning task (a). When environmental cue was red vs. blue vertical stripes, the chicks learned the task quicker (b) and their preference on environmental cue equalled to body-motion cue in the cue conflict test. However when environmental cue was vertical vs. horizontal blue stripes, the chicks showed a preferred dependence on body-motion cue (c). Detour latency was longer for chicks using the environmental cue than chicks using the body-motion cue (d).