[See the thinking brain: a story about water]

Area of Science:

• Physics
• Neuroscience
• Medical Imaging

Context:

• Einstein's 1905 work on molecular diffusion laid the foundation for advanced brain imaging techniques.
• Magnetic Resonance Imaging (MRI) in the 1980s enabled the visualization of water diffusion in the brain.
• Water molecule diffusion probes microscopic tissue structures, revealing functional architecture.

Purpose:

• To explore the brain's functional architecture using molecular diffusion principles.
• To apply diffusion MRI for diagnosing conditions like brain ischemia and understanding white matter organization.
• To investigate diffusion MRI's potential for detecting early neuronal activation.

Summary:

• Diffusion MRI leverages Einstein's molecular diffusion theory to image brain tissue at a microscopic level.
• It detects acute brain ischemia by observing reduced water diffusion due to cytotoxic edema.
• Anisotropic water diffusion in white matter allows mapping of nerve fiber tracts and brain connectivity.

Impact:

• Diffusion MRI provides a non-invasive method to study brain ischemia and white matter structure.
• It offers a potential direct physiological marker for neuronal activation, preceding hemodynamic changes.
• This technique bridges the gap between cellular imaging and human functional neuroimaging.