In "So Much Things to Say," Steffens fixes on more mundane details: the date and the location of recording sessions, the exact occupation of Marley's estranged father (a "ferro-cement engineer," not a naval officer, as is often reported), the jug of mysterious juice that Marley toured with late in life.
There was no significant difference between the location of recording: left (Pz3) vs. right (Pz4) vs. midline (Pz).
The final location of recording and stimulating electrodes was checked histologically at the end of the experiments (Fig. S2).
Fresh-frozen brains were cryostat-cut into 20 µm coronal sections for further validation of the location of recording track into the GP, STN and SNr as previously described [15], [18].
In order to define the location of recording electrodes along the caudo-rostral and medio-lateral axes, a 150 square, mesh gilded nickel grid (Electron Microscopy Sciences, Fort Washington, PA) was glued over the skull opening (inter-hole distance: 170 microns).
The first latency times likely reflected the method of drug administration employed in this study (drugs were added to ACSF), the speed of ACSF perfusion (1 ml/min), the volume of the recording chamber (∼2 ml), the location of recorded neurons within the slice and the location of slices within the recording chamber.
(C ) Location of recording sites as in (B ).
We pooled cells in this way because it was difficult to define the precise location of recording electrodes on each particular recording session.
In the 24 h after electrode implantation, a second MRI 3D T1 sequence was obtained to show the exact location of recording contacts.
(A ) Brain atlas image (Paxinos and Franklin, 2013 ) illustrating bilateral tetrode implantation (top) and location of recording electrodes in Ctrl and KO mice.
