Multi-scale measurement of stiffness in the developing ferret brain

Area of Science:

• Neuroscience
• Developmental Biology
• Biophysics

Background:

• Cortical folding is crucial for brain development.
• Aberrant folding is associated with neurological disorders like autism and schizophrenia.
• Cellular changes influence brain tissue mechanics, but stiffness changes during folding remain unknown.

Purpose of the Study:

• To measure and characterize the mechanical stiffness of developing ferret brain tissue.
• To understand how tissue stiffness evolves during the period of cortical folding.
• To elucidate the biomechanical factors underlying cortical development.

Main Methods:

• Rheometry was used to assess bulk brain tissue properties.
• Atomic force microscopy (AFM) was employed to measure stiffness at the cortical plate level.
• Measurements were taken across multiple length scales in the developing ferret brain.

Main Results:

• Overall brain stiffness significantly increases with age during cortical folding.
• The occipital cortex shows increased stiffness and stiffness heterogeneity during development.
• These findings reveal concurrent changes in tissue properties and folding.

Conclusions:

• Developing brain tissue mechanical properties, specifically stiffness, evolve during cortical folding.
• Quantifying stiffness changes provides critical data for understanding the biomechanics of brain development.
• This research offers a foundation for investigating the role of mechanical properties in neurodevelopmental disorders.