Activation mapping in multi-center retrospective rat sensory-evoked functional MRI datasets using a unified pipeline

Area of Science:

• Neuroscience
• Medical Imaging
• Animal Models

Background:

• Functional Magnetic Resonance Imaging (fMRI) is crucial for studying brain function and disease models in rodents.
• Comparing rodent fMRI data across research institutions is hindered by diverse experimental protocols.
• Standardization is needed to enhance the reliability and comparability of rodent fMRI studies.

Purpose of the Study:

• To analyze current rodent fMRI acquisition practices across multiple imaging centers.
• To identify sources of variability in sensory-evoked fMRI datasets.
• To inform efforts toward standardizing rodent fMRI protocols for improved cross-laboratory comparability.

Main Methods:

• Aggregated and analyzed 22 sensory-evoked rat fMRI datasets from 12 imaging centers (220 rats total).
• Applied a standardized preprocessing pipeline to all datasets.
• Evaluated the impact of different hemodynamic response function models on activity patterns.

Main Results:

• Identified significant inter-dataset variability due to differences in experimental design, anesthesia, and imaging parameters.
• Confirmed robust activation clusters across all analyzed datasets.
• Demonstrated significant variations in statistical maps when comparing human versus rat-specific hemodynamic models.

Conclusions:

• Rodent fMRI studies exhibit considerable variability, impacting reproducibility.
• Standardized protocols and collaborative efforts are essential for enhancing the reliability of rodent fMRI.
• Open access to datasets and code promotes transparency and future research in the field.