Biology subjects

Vallentin, D.

Publications and source records attributed to Vallentin, D..

5 recordsLinked to original sources

bioRxiv2025

Attuning to song duels facilitates song-matching in nightingales

Complex vocal communication requires precise, flexible adjustments to vocal-motor commands for the production of coherent responses to auditory inputs. The mechanisms underlying how such sensorimotor integration controls vocal production is poorly understood. Here, we investigate the dynamics of territorial vocal duels and song-matching in common nightingales (Luscinia megarhynchos). Using a combination of field observations, playback experiments and accelerometry, we find that wild nightingales readily modified the acoustic features of their song, matched the rivals song and engaged more vigorously against vocal opponents with a shared song repertoire. Furthermore, we demonstrate that neurons in the sensorimotor nucleus HVC are tuned to specific song stimuli, potentially enabling context-specific integration of auditory information to facilitate matched song production. These findings highlight the crucial role of song recognition in allowing nightingales to adjust their vocalizations in response to specific social situations, demonstrating the complexity and adaptability of their communication system. Moreover, this study provides a new framework and model system for investigating online sensorimotor processing during dynamic vocal interactions.

neuroscience↗

bioRxiv2025

Nightingales imitate the duration of whistle syllables

While real-time vocal adjustments are crucial for interactive communication, not much is known about the spectral and temporal vocal flexibility of animals. Here, using a combination of field song recordings and controlled playback experiments, we show that wild nightingales imitate whistle song syllable durations in real time. However, when exposed to playbacks with variations in whistle pitch and duration that are beyond their natural range of vocalizations, nightingales emulated temporal or spectral features, approximating the whistle playbacks within the constraints of their natural whistle song repertoire. Our findings reveal a previously unknown dimension of real-time vocal flexibility in songbirds and suggest complex auditory-motor integration during song interactions.

animal behavior and cognition↗

bioRxiv2024

Disinhibition enables vocal repertoire expansion after a critical period

The efficiency of motor skill acquisition is age-dependent, making it increasingly challenging to learn complex maneuvers later in life 1-6. Zebra finches, for instance, acquire a complex vocal motor program during a developmental critical period 7,8 after which the learned song is essentially impervious to modification 9. Although inhibitory interneurons are implicated in critical period closure 10-13, it is unclear whether manipulating them can reopen heightened motor plasticity windows. Using pharmacology and a novel cell-type specific optogenetic approach, we manipulated inhibitory neuron activity in a premotor area of adult zebra finches beyond their critical period. When exposed to auditory stimulation in the form of novel song, manipulated birds added new vocal syllables to their stable song sequence. By lifting inhibition in a premotor area during sensory experience, we reintroduced vocal plasticity, promoting an expansion of the syllable repertoire without compromising pre-existing song production. Our findings provide insights into motor skill learning capacities, offer potential for motor recovery after injury, and suggest avenues for treating neurodevelopmental disorders involving inhibitory dysfunctions.

neuroscience↗

bioRxiv2021

Strong and specific connections between retinal axon mosaics and midbrain neurons revealed by large scale paired recordings

The superior colliculus (SC) is a midbrain structure that plays important roles in visually guided behaviors. Neurons in the SC receive afferent inputs from retinal ganglion cells (RGC), the output cells of the retina, but how SC neurons integrate RGC activity in vivo is unknown. SC neurons might be driven by strong but sparse retinal inputs, thereby reliably transmitting specific retinal functional channels. Alternatively, SC neurons could sum numerous but weak inputs, thereby extracting new features by combining a diversity of retinal signals. Here, we discovered that high-density electrodes simultaneously capture the activity and the location of large populations of retinal axons and their postsynaptic SC target neurons, permitting us to investigate the retinocollicular circuit on a structural and functional level in vivo. We show that RGC axons in the mouse are organized in mosaics that provide a single cell precise representation of the retina as input to SC. This isomorphic mapping between retina and SC builds the scaffold for highly specific wiring in the retinocollicular circuit which we show is characterized by strong connections and limited functional convergence, established in log-normally distributed connection strength. Because our novel method of large-scale paired recordings is broadly applicable for investigating functional connectivity across brain regions, we were also able to identify retinal inputs to the avian optic tectum of the zebra finch. We found common wiring rules in mammals and birds that provide a precise and reliable representation of the visual world encoded in RGCs to neurons in retinorecipient areas. HIGHLIGHTSO_LIHigh-density electrodes capture the activity of afferent axons and target neurons in vivo C_LIO_LIRetinal ganglion cells axons are organized in mosaics C_LIO_LISingle cell precise isomorphism between dendritic and axonal RGC mosaics C_LIO_LIMidbrain neurons are driven by sparse but strong retinal inputs C_LIO_LIFunctional wiring of the retinotectal circuit is similar in mammals and birds C_LI

neuroscience↗

bioRxiv2021

Feed-forward inhibition fine-tunes response timing in auditory-vocal interactions

The ability to regulate vocal timing is a fundamental aspect of communicative interactions for many species, including conversational speech among humans, yet little is known about the neural circuitry that regulates the input-dependent timing of vocal replies. Exploring this topic in the zebra finch premotor area HVC, we identify feed-forward inhibition as a key regulator of vocal response timing. Based on a spiking network model informed by behavioral and electrophysiological data from communicating zebra finches, we predicted that two different patterns of inhibition regulate vocal-motor responses. In one scenario, the strength of production-related premotor inhibition translates into plasticity in vocal response delays. In the other scenario, fast transient interneuron activity in response to auditory input results in the suppression of call production while a call is heard, thereby reducing acoustic overlap between callers. Extracellular recordings in HVC during the listening phase confirm the presence of auditory-evoked response patterns in putative inhibitory interneurons, along with corresponding signatures of auditory-evoked activity suppression. The proposed model provides a parsimonious framework to explain how auditory-vocal transformations can give rise to vocal turn-taking and highlights multiple roles of local inhibition for behavioral modulation at different time scales.

neuroscience↗