Rhd usb interface board

Extracellular voltage recordings were performed using an open source microfabricated silicon electrode array [106 (link),107 (link)] comprised of 128 recording channels spread across four shanks, each of which was spaced 50 μm apart. The probes were coated with a fluorescent dye (Alexa Fluor, Thermo Fisher Scientific, Waltham, MA) and connected to an Intan RHD 128-channel headstage and RHD USB interface board (Intan Technologies, Los Angeles, CA).
After the recovery period, animals were head-fixed into the run-wheel in the virtual reality rig. The electrode array was placed on a stereotactic frame and guided to the location of the craniotomies. For dCA1, the probe was lowered 1–1.2 mm from the brain surface and for vCA1, the probe was lowered 4–4.2 mm from the brain surface. Two days of recordings were performed for each mouse. For most animals, each day of recording comprised of one 1-2h session in dCA1 and one 1-2h session in vCA1. Signals were acquired at 30kHz in the 0.1–3500 Hz frequency band.

After the implantation of the probe in the acute surgery, the animal was placed inside a TEM cell and the depth of the silicon probe was fine-tuned using the micro-drive. Once the target depth (4 mm from surface of the brain) was reached, we waited at least 30 minutes before data collection. We recorded 30 min pre-stimulation baseline, 300 trials of intermittent RF stimulation (three different intensities were applied at 950 MHz, 5.4, 8.9 and 37.5 W, respectively; 3 s RF-ON was followed by 3 s RF-OFF epoch for each intensity) and 30 min post-stimulation baseline. The recorded signals (n = 64 channels) were amplified and stored after digitization at 20 kHz sampling rate per channel (RHD USB Interface Board, Intan Technologies). After the experiment, the silicon probe was recovered and cleaned in distilled water. Animals were humanely euthanized after the end of the post-surgery experiments.