Revealing the biological bases of speech and language by studying bat vocal learning

Project Information

BATSPEAK

Grant agreement ID: 101001702

DOI

10.3030/101001702

EC signature date 12 October 2021

Start date 1 May 2022

End date 30 April 2029

Funded under

• EXCELLENT SCIENCE - European Research Council (ERC)

Total cost

€ 1 935 402,99

EU contribution

€ 1 935 402,99

Coordinated by

THE UNIVERSITY COURT OF THE UNIVERSITY OF ST ANDREWS
United Kingdom

Periodic Reporting for period 2 - BATSPEAK (Revealing the biological bases of speech and language by studying bat vocal learning)

Reporting period: 2023-11-01 to 2025-04-30

Summary of the context and overall objectives of the project

The biological origins of speech and language are not fully understood. Scientists are intrigued by how the capacity for speech and language evolved in humans. The BATSPEAK project aims to uncover the biological basis of speech by studying how bats learn to produce sounds (known as vocal learning). A trait they share with humans, but few other mammals, bats can modify their vocalizations based on experience, making them a valuable model for understanding the foundations of human spoken language. By studying bats, the ERC-funded BATSPEAK project aims to shed light on the neuromolecular mechanisms that support vocal learning and are affected by language disorders.
Understanding vocal learning is crucial not only for tracing the evolution of speech but also for addressing communication disorders. Millions of people worldwide suffer from conditions such as autism, developmental language disorder, and speech apraxia, which impact their ability to communicate effectively. By identifying the molecular and neural mechanisms behind vocal learning, BATSPEAK could help improve the diagnosis and treatment of these disorders. This research may also lead to the development of new therapies for speech-related impairments.
To achieve this, scientists will study the genetic and brain mechanisms that allow bats to learn new sounds. By analysing bat DNA, they hope to identify key genes that play a role in vocal learning. They will also examine how different parts of the bat brain work together to produce sounds and compare these findings to what is known about human speech. Finally, researchers will test how specific genes influence vocal behaviour by making temporary genetic changes in bats and observing how this affects their ability to learn sounds.
By combining studies of genetics, brain activity, and behaviour, BATSPEAK will provide new insights into the origins of speech. This knowledge could help researchers better understand speech-related disorders and explore new ways to treat them. The project will also offer clues about how vocal communication evolved in mammals, bringing us one step closer to understanding the deep biological roots of human language.

Work performed from the beginning of the project to the end of the period covered by the report and main results achieved so far

The BATSPEAK project is breaking new ground in understanding how bats learn to communicate. Our research has focused on uncovering the neurogenetic mechanisms that enable vocal learning, a rare ability shared by humans, songbirds, and some bat species. By studying these animals, we hope to reveal fundamental insights into speech and language development and associated disorders.
In the initial period, we have established the groundwork to achieve the goals of the BATSPEAK project. To better understand how bats acquire and modify their calls, we have developed new tests of behaviour, including automated training systems that allow bats to learn vocal modifications in a controlled setting. In addition we are developing hand-training techniques where human experimenters work directly with bats to shape their vocal behaviors, and Y-maze tasks to test their perception and decision-making. These innovations provide us with unprecedented precision in studying the learning process.
In parallel, we have pioneered the world’s first transgenic bat models—bats that have been genetically modified to help us understand how specific genes influence their ability to learn new sounds. Alongside this, we are developing cutting-edge neural techniques such as electrophysiological recordings and calcium imaging, which allow us to observe real-time brain activity in vocal learning-related areas. By combining these neural recordings with behavioral experiments, we are gaining deeper insights into how the bat brain processes and adapts to new vocal patterns.
By integrating genetics, neuroscience, and behavior studies, BATSPEAK is pushing the boundaries of what we know about vocal learning. The insights gained from this research have the potential to improve our understanding of speech disorders and the evolution of language.

Progress beyond the state of the art and expected potential impact (including the socio-economic impact and the wider societal implications of the project so far)

The BATSPEAK project is poised to make new discoveries in the study of vocal learning, which could have implications for understanding and treating language disorders in humans. By the end of the project, we expect to have significantly advanced our knowledge in three key areas: identifying the genetic foundations of vocal learning, mapping neural circuits responsible for this ability, and experimentally testing the role of these factors in vocal learning behaviour.
Through evolutionary and functional genomics, we will pinpoint key genes that contribute to vocal learning in mammals. By investigating their functions we will generate hypotheses about how these genes influence speech-related neural processes. This knowledge is critical in identifying genetic variants that may be linked to language disorders, providing a foundation for future studies on therapeutic interventions.
We will focus on characterizing the neural mechanisms underlying mammalian vocal learning. By investigating a key brain circuit responsible for vocal control, we will uncover parallels between bats and humans. This research will use neurophysiological and transcriptomic approaches to investigate how neurons in this pathway communicate to produce learned vocalizations. Comparing these findings to human brain data will highlight conserved neural structures and functions relevant to speech. Identifying commonalities in vocal learning across species will provide valuable insights into disorders such as stuttering, apraxia, and other speech impairments that result from disruptions in neural circuits controlling vocal production.
By employing our successful transgenic bat models we will be able to understand how genes involved in speech disorders contribute to vocal learning behaviour. Behavioral assays—including automated vocal training, hand training, and Y-maze discrimination tasks—will be used to evaluate how genetic changes involved in disorders influence the ability of bats to modify their vocalizations in response to social cues. Additionally, neural techniques such as calcium imaging will allow us to observe real-time brain activity associated with vocal learning. These models will provide an unprecedented opportunity to test hypotheses about speech disorders.
The long-term impact of BATSPEAK will extend beyond the immediate discoveries in vocal learning. By elucidating the genetic and neural foundations of this ability, the project will create new pathways for research into human speech and its disorders. The insights gained may contribute to the development of novel strategies to understand and address communication deficits in individuals with speech disorders. Ultimately, BATSPEAK will not only transform our understanding of mammalian vocal learning but also provide critical knowledge that could improve the lives of those affected by language impairments.

Structure and expression patterns in the brain of the vocal learning bat, P. discolor