Mechanobiology of Brain Function
Classic electrochemical models of action potentials and neuronal information processing, integration, and transfer do not account for the influence of physical factors (mechanobiology) on cellular communication and plasticity in the brain. New insights into how the physical properties of neurons govern their communication will expand our understanding of the 'neural code'.
The brain, its neural circuits, and molecular cellular components are mechanically sensitive. Cellular membranes, cytoskeletal elements, other scaffolding proteins, ion channels, and even synapses sense, generate, and transduce micromechanical forces during ongoing brain activity (above). These physical forces must cooperate with electrical and biochemical cues in the brain to regulate function, growth/development, and plasticity. However, neuroscience has yet to address how the basic mechanosensitive features and viscoelastic properties of the brain, glia, and neurons give rise to functional outcomes. Our interests in these problems gave rise to our observations that pulsed ultrasound can be used to stimulate brain circuit activity.
Mechanobiology & Sites of Action for Ultrasonic Neuromodulation
To understand better how ultrasound stimulates and modulates neuronal activity, we have been investigating how low-intensity pulsed ultrasound acts upon membrane and cytoskeletal dynamics, as well as ion channel activity.
Pulsed ultrasound modulates the lateral pressure profile and surface tension of phospholipid membranes.
Pulsed ultrasound modulates the stress-strain profile of actin cytoskeleton elements.
The mechanical pressures exerted by low-intensity pulsed ultrasound modulates the activity of individual ion channels.