E-Scope in a Rat (ephys + miniscope)

[Kayla Vokt]

Hello,

Has anyone been able to simultaneously record ephys and miniscope ipsilaterally? What design approaches have been successful? I would like to achieve this in the CA1 region of a rat.

I was wondering about the latest development of the E-Scope.  Would this work with Miniscope v3 and v4, or is there potentially an issue with noise from the electro-wetting lens of v4?

Thank you!
-Kayla

 

[Brandon Coventry]

Hi Kayla,

We have been able to, though in different brain regions ipsilateral. We've done imaging with single units with no discernable noise from the lens. CA1 might be broad enough to implant recording arrays and grin lenses, but it becomes tricky when trying to give enough space for baseplating.

[Nat Kinsky]

Hi Kayla,

I have done a number of recordings with a v4 scope (Labmaker, I assembled) in rat PFC and a 32 channel linear probe in CA1.  I see a lot of electrical noise from the EWL when I do so and my attempts to eliminate it by wrapping the lens in copper tape were unsuccessful. However, the noise is concentrated in a fairly narrow band (~4840-4855Hz) and its harmonics, so I have been able to remove it post-hoc with a notch filter and resolve single units.  I use a low-pass filter during recording (1-1250Hz) in OpenEphys to make sure everything looks ok, and then record the unfiltered raw data.  The only time I have not seen this noise was when the EWL was not properly powered.  See this post for more details.  I did not see any noise with the v3 scope.

I agree that things might be a bit tight for recording in the same region. I chronically attach the scope to the rat's skull without a baseplate (thanks to Evan Hart for this idea!) and then build up a protective cage. You could try something like this to save space, potentially.

Nat