Miniaturized optical neuroimaging in unrestrained animals

Area of Science:

• Neuroscience
• Biomedical Engineering
• Optical Imaging

Background:

• Traditional in vivo functional neuroimaging in rodents required anesthesia and restraint, limiting experimental possibilities.
• Technological advancements in optics, electronics, and computation have enabled new neuroimaging approaches.

Purpose of the Study:

• To review recent advances in miniaturized, head-mounted optical neuroimaging systems for studying cortical function in unrestrained, unanesthetized rodents.
• To highlight the capabilities of these systems in assessing brain activity and disease models.

Main Methods:

• Classification of systems based on exogenous contrast agents (e.g., single- and two-photon microscopy).
• Classification of systems based on endogenous contrast mechanisms (e.g., multispectral imaging, laser speckle contrast imaging).

Main Results:

• Miniaturized head-mounted optical systems now permit functional neuroimaging in awake, unrestrained rodents.
• These systems allow assessment of blood flow and oxygenation changes related to neural activity.
• Applications include imaging functional responses in disease models like stroke, seizure, and tumors.

Conclusions:

• These technological advances provide unprecedented insights into mammalian brain organization and function.
• They aid in understanding neural 'dysfunction' in various central nervous system disease models.
• Future perspectives on the strengths, weaknesses, and trajectory of optical neuroimaging are discussed.