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Biology subjects

Mastik, F.

Publications and source records attributed to Mastik, F..

2 recordsLinked to original sources

Mobile Human Brain Imaging using Functional Ultrasound

Imagine being able to study the human brain in real-world scenarios while the subject displays natural behaviors such as locomotion, social interaction, or spatial navigation. The advent of ultrafast ultrasound imaging brings us closer to this goal with functional Ultrasound imaging (fUSi), a new mobile neuroimaging technique. Here, we present real-time fUSi monitoring of brain activity during walking in a subject with a clinically approved sonolucent skull implant. Our approach utilizes personalized 3D-printed fUSi-helmets for stability, optical tracking for cross-modal validation with fMRI, advanced signal processing to estimate hemodynamic responses and facial tracking of a lick licking paradigm. These combined efforts allowed us to show consistent fUSi signals over 20 months, even during high-motion activities like walking. These results demonstrate the feasibility of fUSi for monitoring brain activity in real-world contexts, marking an important milestone for fUSi-based insights in clinical and neuroscientific research.

neuroscience↗

3D Functional Ultrasound Imaging of Pigeons

Recent advances in ultrasound Doppler imaging have allowed to visualize brain activity in small mammalian species such as rats and mice. In birds, this type of functional ultrasound imaging was impossible up to now because birds have physiological characteristics that are unfavorable for current functional ultrasound acquisition schemes. Here, we introduce a high-definition functional ultrasound acquisition method (HDfUS) acquiring 20,000 frames per second continuously. This enabled first successful functional studies on awake pigeons subjected to auditory and visual stimulation. We show that the improved spatiotemporal resolution and sensitivity of HDfUS allows to visualize and investigate the temporally resolved 3D neural activity evoked by a complex stimulation pattern, such as a moving light source. This illustrates the enormous potential of HDfUS imaging to become a new standard functional brain imaging method revealing unknown, stimulus related hemodynamics at excellent signal-to-noise ratio and spatiotemporal resolution.

neuroscience↗