PT - JOURNAL ARTICLE AU - Jeeun Kang AU - Haichong K. Zhang AU - Shilpa D. Kadam AU - Julie Fedorko AU - Heather Valentine AU - Adarsha P. Malla AU - Ping Yan AU - Maged M. Harraz AU - Jin U. Kang AU - Arman Rahmim AU - Albert Gjedde AU - Leslie M. Loew AU - Dean F. Wong AU - Emad M. Boctor TI - Transcranial recording of electrophysiological neural activity in the rodent brain <em>in vivo</em> using functional photoacoustic imaging of near-infrared voltage-sensitive dye AID - 10.1101/202408 DP - 2019 Jan 01 TA - bioRxiv PG - 202408 4099 - http://biorxiv.org/content/early/2019/01/14/202408.short 4100 - http://biorxiv.org/content/early/2019/01/14/202408.full AB - Minimally-invasive monitoring of electrophysiological neural activities in real-time—that enables quantification of neural functions without a need for invasive craniotomy and the longer time constants of fMRI and PET—presents a very challenging yet significant task for neuroimaging. In this paper, we present in vivo functional PA (fPA) imaging of chemoconvulsant rat seizure model with intact scalp using a fluorescence quenching-based cyanine voltage-sensitive dye (VSD) characterized by a lipid vesicle model mimicking different levels of membrane potential variation. The framework also involves use of a near-infrared VSD delivered through the blood-brain barrier (BBB), opened by pharmacological modulation of adenosine receptor signaling. Our normalized time-frequency analysis presented in vivo VSD response in the seizure group significantly distinguishable from those of the control groups at sub-mm spatial resolution. Electroencephalogram (EEG) recording confirmed the changes of severity and frequency of brain activities, induced by chemoconvulsant seizures of the rat brain. The findings demonstrate that the near-infrared fPA VSD imaging is a promising tool for in vivo recording of brain activities through intact scalp, which would pave a way to its future translation.