Biology subjects

Calhoun, A. J.

Publications and source records attributed to Calhoun, A. J..

4 recordsLinked to original sources

bioRxiv2025

Recent social experience alters song behavior in Drosophila

Innate behaviors are hardwired into the nervous system, allowing animals to produce them instinctively and without prior learning. This includes social behaviors (e.g., aggression, courtship) in most animals. If and how learning shapes such innate behaviors has not been systematically explored. Here, we investigate learning from social feedback in Drosophila. We use closed-loop optogenetics to systematically perturb the social experience of individual flies during courtship, and find that altered feedback changes the male flys innate courtship strategy, opening the door for investigating the neural and molecular basis of social plasticity in flies. TeaserMale flies adjust their innate communication strategy in response to systematic perturbation of social experience.

neuroscience↗

bioRxiv2022

One-to-one mapping between deep network units and real neurons uncovers a visual population code for social behavior

The rich variety of behaviors observed in animals arises through the complex interplay between sensory processing and motor control. To understand these sensorimotor transformations, it is useful to build models that predict not only neural responses to sensory input [1, 2, 3, 4, 5] but also how each neuron causally contributes to behavior [6, 7]. Here we demonstrate a novel modeling approach to identify a one-to-one mapping between internal units in a deep neural network and real neurons by predicting the behavioral changes arising from systematic perturbations of more than a dozen neuron types. A key ingredient we introduce is "knockout training", which involves perturb-ing the network during training to match the perturbations of the real neurons during behavioral experiments. We apply this approach to model the sensorimotor transformation of Drosophila melanogaster males during a com-plex, visually-guided social behavior [8, 9, 10]. The visual projection neurons at the interface between the eye and brain form a set of discrete channels, suggesting each channel encodes a single visual feature [11, 12, 13]. Our model reaches a different conclusion: The visual projection neurons form a highly distributed population code that collectively sculpts social behavior. Overall, our framework consolidates behavioral effects elicited from various neural perturbations into a single, unified model, providing a detailed map from stimulus to neuron to behavior.

neuroscience↗

bioRxiv2020

The Neural Basis for a Persistent Internal State in Drosophila Females

Sustained changes in mood or action require persistent changes in neural activity, but it has been difficult to identify and characterize the neural circuit mechanisms that underlie persistent activity and contribute to long-lasting changes in behavior. Here, we focus on changes in the behavioral state of Drosophila females that persist for minutes following optogenetic activation of a single class of central brain neurons termed pC1. We find that female pC1 neurons drive a variety of persistent behaviors in the presence of males, including increased receptivity, shoving, and chasing. By reconstructing cells in a volume electron microscopic image of the female brain, we classify 7 different pC1 cell types and, using cell type specific driver lines, determine that one of these, pC1-Alpha, is responsible for driving persistent female shoving and chasing. Using calcium imaging, we locate sites of minutes-long persistent neural activity in the brain, which include pC1 neurons themselves. Finally, we exhaustively reconstruct all synaptic partners of a single pC1-Alpha neuron, and find recurrent connectivity that could support the persistent neural activity. Our work thus links minutes-long persistent changes in behavior with persistent neural activity and recurrent circuit architecture in the female brain.

neuroscience↗

bioRxiv2019

Unsupervised identification of the internal states that shape natural behavior

Internal states can shape stimulus responses and decision-making, but we lack methods to identify internal states and how they evolve over time. To address this gap, we have developed an unsupervised method to identify internal states from behavioral data, and have applied it to the study of a dynamic social interaction. During courtship, Drosophila melanogaster males pattern their songs using feedback cues from their partner. Our model uncovers three latent states underlying this behavior, and is able to predict the moment-to-moment variation in natural song patterning decisions. These distinct behavioral states correspond to different sensorimotor strategies, each of which is characterized by different mappings from feedback cues to song modes. Using the model, we show that a pair of neurons previously thought to be command neurons for song production are sufficient to drive switching between states. Our results reveal how animals compose behavior from previously unidentified internal states, a necessary step for quantitative descriptions of animal behavior that link environmental cues, internal needs, neuronal activity, and motor outputs.

neuroscience↗