ABS 2022
Neural basis of turn-taking in the duetting plain-tailed wren
Melissa J Coleman1, Nancy Day2, Eric Fortune3. 1Scripps College, Claremont, California, United States; 2Whitman College, Walla Walla , Washington, United States; 3New Jersey Institute of Technology, Newark, New Jersey, United States

Plain-tailed wrens live on the slopes of the Andes in Ecuador. Female and male wrens coordinate alternation of their syllables so precisely it sounds as if a single bird is singing. To understand the neural basis of this turn-taking behavior, my collaborators and I conducted research at remote field sites in Ecuador. Initial field audio recordings revealed that female and male wrens sing solo and duet song. The basic pattern of syllables in solo song was similar to that during duets, but the inter-syllable interval timing was altered. This suggested the brain of each bird produced the pattern for song, and that auditory feedback from the partner modulated the timing of the pattern. To determine if this was the case, we made wireless, electrophysiological recordings from pairs of wrens while they sang duets. We found that neurons in a specific area of the brain, HVC, were active when the bird was singing, and were inhibited while the bird listened to its partner. That is, the timing of the ongoing motor pattern was inhibited by input from the partner. Therefore, this cooperative, turn-taking behavior is produced by a single neural circuit that is shared across two individuals.