A Protocol for Microprism-Based Two-Photon Imaging Of The Lateral Cortex In The Mouse Inferior Colliculus.

Area of Science:

• Neuroscience
• Auditory System Research
• Brain Imaging Techniques

Background:

• The inferior colliculus (IC) is crucial for auditory processing, with subdivisions like the lateral cortex (LC) receiving multisensory inputs.
• The LC's deep location within a sulcus hinders in vivo imaging, limiting studies on its functional organization.
• Understanding LC function is vital for deciphering complex auditory information processing.

Purpose of the Study:

• To introduce a novel protocol for imaging the LC in behaving animals using two-photon microscopy and a microprism.
• To investigate neuronal responses and functional organization within the LC in relation to its molecular motifs.
• To enable functional mapping of previously inaccessible brain regions.

Main Methods:

• Developed a protocol combining two-photon microscopy with a microprism for cellular-resolution sagittal imaging of the LC.
• Performed craniotomy and microprism implantation in animal models.
• Acquired data from sound-responsive neurons and analyzed neuronal responses to pure tones.
• Generated best-frequency tuning maps to assess functional organization.

Main Results:

• Successfully obtained cellular-resolution sagittal views of functional LC maps.
• Investigated neuronal responses to pure tones, revealing insights into LC organization.
• Demonstrated the feasibility of imaging deep, previously inaccessible brain regions.

Conclusions:

• The microprism-based two-photon microscopy technique provides a powerful new tool for studying the LC.
• This method offers unprecedented insights into the auditory system's functional organization.
• The technique has broad applicability for imaging other hidden brain structures.