Voiced sound production is the primary form of communication in mammals and birds and essential to human identity and artistic expression. The Vocal Neuromechanics Lab aims to understand the physical principals and motor control of sound production for vocal communication. We strive to build an integrated model of vocal motor control in mammals and songbirds.

With a main focus on the songbird system, we are interested in how all vertebrates transform neural code into extremely precise behaviors using the fastest muscles evolved. Our work therefore lies at the fascinating interface of neuroscience, biomechanics, muscle physiology, morphology and evolution.

We integrate comparative laboratory and computational model studies and have developed several innovative experimental setups to study voice production and muscle physiology from in vitro and ex vivo (whole organ) to in vivo.

Recent discoveries from the lab

Physical mechanisms for making sound

• We found that birds make sound using the same physical mechanisms as mammals do. In songbirds we have a much more detailed understanding how neurons in the brain contribute to song compared to human, but we didn't know how sound was produced and still don't know much about how sound is actually controlled. Our finding allows us to tap into over 60 years of knowledge on the human voice to jumpstart our understanding of sound production and control in birds.
• We discovered that mice make their ultrasonic courtship songs by tiny whistles in their larynx, a mechanism that has only been observed by supersonic jet engines. It is important to understand how mice make their ultrasonic love songs because they are a vital tool for linking gene mutations to behavior in mouse models of communication disorders, such as autism.
• How do you make sound with a larynx when you return to water and have no airflow available? We discovered that the fully aquatic African clawed frogs evolved a novel mechanism of sound production using a heavily modified larynx.

Superfast motor control of sound production

Superfast muscles are the fastest synchronous vertebrate muscles known and due to their extreme performance have provided valuable insights in basic muscle cell functions, such as rate-limiting steps during excitation-contraction coupling. The phenotype was thought to be extremely rare, but work from our lab has showed it to be ubiquitous in vocal control in birds and mammals and crucial for their communication and survival. In 2017 we showed that SFM operate at a maximum operational speed set by fundamental constraints in synchronous muscle. These constraints set a fundamental limit to the maximum speed of fine motor control.

Innovations

In the lab we use a variety of in vivo, ex vivo and in vitro experimental physiological techniques combined with various forms of high-speed imaging, such as high-speed imaging, calcium imaging and microCT.

• To study the physiology and mechanical performance of muscle we have developed several novel experimental in vitro setups specially adapted to record from so-called superfast muscles, the fastest vertebrate synchronous muscle phenotype.
• Furthermore we designed and developed novel paradigms to study perfused vocal organs of small vertebrates in vitro and ex vivo, which allows unprecedented experimental control and high-resolution imaging during sound production events. * Recently we developed methods to quantify force on and motion of elements, finally allowing application of the powerful toolbox of biomechanics to avian vocal motor control.