@phdthesis{oai:oist.repo.nii.ac.jp:00001138,
 author = {Dalphin, Neil},
 month = {2019-11-06, 2019-11-06},
 note = {The supragranular layers of cortex are key information integration and computation areas with dominant cortico-cortical connections. While layers 2 and 3 are densely packed with somata, layer 1 is almost free of somata. The absence of somata makes the analysis of layer 1 difficult. Electrical recording from small processes within layer 1 are not possible and electric field recordings are difficult due to the low seal resistance. Imaging processes of layer 1 remains difficult as cells project into it from many distant areas and due to the dense and intermingled packing.
Here, I record sensory signals in supragranular layers, including layer 1 through a combination of voltage sensitive dye imaging, and an intracellular calcium indicator. Optical sectioning with two-photon microscopy allowed resolution in depth, showing changes in the sensory signal within layer 1. Additionally, cortical oscillations were detected with the voltage-sensitive dye in the delta, theta, and beta bands, and, for the first time with voltage imaging, also in the slow-gamma (35 Hz) band, in vivo. Delta, theta, and gamma oscillations were modulated by sensory stimuli.
As very little is known about membrane voltage oscillations in layer 1 and to optimize optical voltage recordings in layer 1, I developed a novel surgery to apply voltage dye primarily to layer 1, without removing the dura or injecting dye within the brain. I also applied a new voltage-sensitive dye optimized for tissue diffusion with this surgery. I imaged cortical membrane potential oscillations with two-photon microscopy depth-resolved (25 to 100 µm below dura) in anesthetized and awake mice. Again, I found delta (0.5-4 Hz), theta (4-10 Hz), low beta (10-20 Hz), and low gamma (30-40 Hz) oscillations. All oscillation bands were stronger in awake animals. While the power of delta, theta, and low beta oscillations increased with depth, the power of low gamma was more constant throughout layer 1. These findings identify layer 1 as an important coordination hub for the dynamic binding process of neurons mediated by oscillations.},
 school = {Okinawa Institute of Science and Technology Graduate University},
 title = {マウスバレル皮質顆粒上層における二光子膜電位イメージング：振動と応答},
 year = {}
}