Extended Data Fig. 14: Posture of the animal during data collection.

a, Site-Localization. The chambers for deep brain recordings were designed to be positioned at an optimum angle to prevent possible injuries to large blood vessels. In more than 30 reversible experiments with electrodes under anaesthesia, the animals – with few exceptions – did not show any complications as a result of the electrode placement in the pons region. Figure: Example design of a pons chamber using MR angiography. The Brainsight system (Rogue Research, https://www.rogue-research.com/) was used for the precise implantation of electrophysiology chambers aimed to explore deep brain structures (for example, the lateral geniculate nucleus, and the parabrachial nucleus). Before the surgery, anatomical scans of the animal’s head were produced with markers to obtain data on the skull shape and pertinent target structures for tailor-made implants. The brain-vasculature was reconstructed, and a path with lowest probability of hitting large vessels/arteries was chosen. During the surgery, the position of the implant was determined by the Brainsight computer programme, which can superimpose a virtual implant with its trajectory and targets on the reconstructed skull using the pointer tool. These techniques can prevent the undesirable misplacement of recording chambers, which could be the case when there is a small difference in shape between the skull and the implant (for example, an angle of 5 degrees causes a shift of about 2.6 mm under a 30-mm chamber. This shift would be sufficient to miss a smaller deep brain structure). At right of panel a, is an example of multisite/multilaminar electrode in two magnifications. b, Placement of the electrodes before the combined physiology-fMRI experiments. c, It shows the posture of the animal during the experiment. Due to the fact that all magnets were vertical for reducing any stress to the animal in alert monkey experiments, the anaesthetized monkeys were prepared with all measure for maintaining normal blood pressure (foot-bandage), and temperature, as well as for measuring of physiological parameters. During the maintenance of aneesthesia, as well as data collection, the animal was always in a “sitting” position with closed eyes with all necessary items for the maintenance of anaesthesia and measurement of physiological parameters. d, The animal before shifting the chair into the magnet.