Periodic Reporting for period 1 - WORD (Wireless Optogenetics to elucidate the function of corticostriatal neurons in biRDsong)
Berichtszeitraum: 2022-02-01 bis 2024-01-31
Birdsong has long been used as a model for human speech due to their many shared attributes: both are acquired from conspecifics through processes involving repeated vocal practice and auditory-feedback-guided adjustments. Also, both humans and songbirds have specialized brain circuits for vocal learning and production. These circuits involve corticostriatal neurons that are associated with speech impairments and that underlie diseases such as autism spectrum disorder and Huntington’s and Parkinson's diseases. Despite these parallels, the functional roles of this neuron population in vocal behaviors are not well understood.
To research this neuron circuit, new viral tools are needed capable of targeting corticostriatal neuron populations in songbirds. Furthermore, to research these circuits in animals that freely behave and that live in naturalistic environments, new engineered devices are needed to interrogate the brain such as wireless animal-borne sensors and stimulators. Such devices promise to allow tether-free experiments without imposing any movement restriction of experimental animals.
To research this neuron circuit, new viral tools are needed capable of targeting corticostriatal neuron populations in songbirds. Furthermore, to research these circuits in animals that freely behave and that live in naturalistic environments, new engineered devices are needed to interrogate the brain such as wireless animal-borne sensors and stimulators. Such devices promise to allow tether-free experiments without imposing any movement restriction of experimental animals.
To make progress with viral circuit targeting, a new virus for optogenetic inhibition was constructed in collaboration with the Viral Vector Facility of the University of Zurich, scAAV-DJ/9/2-hSyn1-chI-eArchT3.0-SV40p(A). To advance tether-free experiments in freely behaving zebra finches, a new Bluetooth Low Energy wireless device was produced in collaboration with the Center for Project-based Learning of the ETH Zurich. Furthermore, new algorithms for real-time detection of song components were developed capable of running on the on-board processor of the wireless device.
Previous animal-borne sensor devices required frequent wireless communication between the freely moving animal and a host computer, which introduces signal latencies and consumes a lot of energy. To avoid these shortcoming, the newly developed device allows performing the required computations merely using the on-board processing capabilities, which eliminates communication delays and increases the longevity of the battery-powered device, which now for the first-time achieves a day-long operation. Given this progress, the main barrier towards research on brain circuits in freely behaving songbirds has been lifted, which constitutes an important advance with beneficial impact on the welfare of animals in experiments.