Hi there,
I normally record from both mouse brain hemispheres (dorsomedial and dorsolateral striatum) and have noticed that when my ground pin (closer to the cerebellum) is on the same hemisphere as the electrophysiology recording there is more overall noise. Is that typical? The farther the ground pin the less noise using Neuropixels?
Thanks!
Selena
Hi Selena – in principle the hemisphere of the ground pin should not make much of a difference, but grounding is of course notoriously finicky. Are you doing acute or chronic recordings? The troubleshooting procedure will differ a lot depending on which approach you’re taking.
I would also recommend posting this question on the Neuropixels slack channel – that’s the best place to get feedback about specific details of Neuropixels experiments.
Thanks Josh for your quick response! I am doing acute recordings. Thanks for the slack channel recommendation. I will definitely be posting this question there.
For our acute recordings, we don’t use a ground pin at all – if the ground pin is slightly unstable, this can result in noise. Instead, we cover the brain with an agarose mixture made with ACSF, and make sure the ground wire is in contact with this. The full protocol is available here: Acute head-fixed recordings in awake mice with multiple Neuropixels probes | Nature Protocols