Abstract Preclinical small animal imaging makes valuable contributions to improving our understanding of human brain. Multi-modal imaging approaches to combine functional Magnetic Resonance Imaging (fMRI) with Intracranial Electroencephalogram (iEEG) provides an unparalleled view of the global network activity across cortical areas, revealing information at high temporal and spatial scales about functional connectivity and their intrinsic oscillatory properties, which is of vital importance in many branches of neuroscience and medicine. Despite this clear advantage, the use of iEEG-fMRI is limited in small animal research. The existing MRI compatible headstages on the market for small animals are inadequate to acquire high-fidelity iEEG-fMRI. Working within this premise, the long-term goal of this project is to develop a headstage for high-fidelity recording and stimulation in small animals. We propose to unlock high-fidelity iEEG-fMRI imaging paradigm leveraging our patented innovative MRI-compatible electrode- grid (PTFOS) which is based on organic-absorbable, stretchable, and conformable substrate for optimal safety, flexibility and performance with distinct advantages over other neural grids. Phase I of this application proposes to develop HF-2 acquisition prototype which will fit into animal MRI bore recording constraints and tests its feasibility in rats during high-field MRI (9.4Tesla) at Massachusetts General Hospital. Phase II focuses on adding stimulation module, commercialization and miniaturization of HF-2 into a tiny headstage.