With the central ability to visualize a variety of endogenous chromophores and biomarkers or exogenous contrast agents, optoacoustic (photoacoustic) imaging empowers new experimental capabilities for investigating brain mechanisms and functions. Here, the operational principles of optoacoustic neuroimaging are reviewed in conjunction with recent advances enabling high-resolution and real-time observation, which extend beyond the reach of optical imaging methods. Multiple implementations of optoacoustics for monitoring hemodynamics and neuro-vascular responses in the brain are showcased. The unique capabilities of optoacoustic imaging for multi-spectral cellular and molecular sensing are discussed with reference to recent application for visualizing healthy and diseased brains. Outstanding challenges in the field are considered in the context of current and future applications of optoacoustic neuroimaging for basic and translational neuroscience research. In pushing the boundaries of brain imaging, optoacoustic methods afford major insights into the neuronal mechanisms of brain functions and organization of behavior.
