BOLD MRI response to optogenetic activation of cerebral blood vessel cells in intact mouse brains

Motivation: The ultimate objective of this work is to develop novel tools for studying neurovascular coupling and manipulating cerebral blood flow in vivo, with potential therapeutic intervention applications on cerebral vascular-related disease. Goal(s): We present a novel, non-invasive approach to non-invasively modulating brain hemodynamics. Approach: by leveraging an ultra-sensitive opsin channel to photosensitize cerebral blood vessels in genetically - targeted brain regions. Results: Using light stimulation, we achieved targeted vasoconstriction and induced a negative BOLD MRI response without the need for invasive optical implants. SOUL opsin's high light sensitivity allows for effective activation at low power densities, demonstrating its potential for precise neuromodulation. Impact: This work is the first to showcase the use of an ultrasensitive opsin to modulate hemodynamic signals transcranially without the need for invasive optical cannula implantation, marking a significant advancement in non-invasive genetically targeted hemodynamic modulation strategies.