Task and behavior.

A. Task timeline. Each trial started with an auditory start cue, followed by a 0.5 s delay. Next, the stimulus could occur anytime during a 2 s stimulation window. After a variable 0.5 to 1 s delay, a response cue prompted patients to answer whether or not they detected the stimulus. B. Two example sets of 1 s long microelectrode recordings along the surgical tract showing specific firing for the subthalamic nucleus (left) and the motor thalamus (right). The depth at which the research data was collected is represented as a red dot (see Supplementary Figure 1 for anatomical correspondence). C. Number of hits, misses, correct rejections (C.R.), and false alarms (F.A.) collected during the main experiment. D. Averages of the absolute vibrotactile intensity in hits and misses in arbitrary units (values cannot be compared between participants). In panels C and D, each small dot represents a participant with Parkinson’s Disease (PD, in green) or essential tremor (ET, in orange). Big dots represent averages; error bars represent 95% confidence intervals.

Representative cue- and task-responsive neurons in distinct patients.

A-C. Upper panels: firing rates time-locked to the onset of a trial (300 ms long auditory cue; vertical purple shade), compared to a 500 ms pre-cue baseline (“B”). Two significance windows were tested: the post-cue window (500 ms after cue offset; grey horizontal bar; cue-selective neurons) or the stimulation window (800 ms to 2800 ms post-cue; black horizontal bar; task-selective neurons). Asterisks represent statistical significance (p < 0.05). Shaded areas indicate bootstrapped standard errors. Inset: corresponding action potentials (shaded area indicates standard deviation; vertical bar corresponds to 100 μV). Lower panels: raster plot with trials sorted by stimulus onset (dashed lines) and type: hits (blue), misses (red), correct rejections (C.R.; green), and false alarms (F.A.; black). A. Cue-selective neuron in the thalamus. B. Cue- and task-selective neurons in the STN. C. Task-selective neuron in the thalamus. D. Sagittal view of recording locations for thalamic (squares) and subthalamic (circles) targets (see Figure S3A for a coronal view). Filled circles or squares are cue/task-selective neurons. Legend: VL: ventral lateral thalamus, VPlm: ventral posterior lateral and medial thalamus, VPi: ventral posterior inferior thalamus, STN: subthalamic nucleus, SN: substentia nigra, GPi/e: globus pallidus internalis / externalis,

Representative stimulus-responsive neurons in distinct patients.

A-C. Upper panels: firing rate time-locked to the onset of the stimulus (100 ms vibrotactile stimulation; blue sinusoid) for all trials. Green trace represents corresponding activity for catch trials. Thick horizontal black segments show significant time windows. Shaded areas indicate bootstrapped standard errors. Inset: corresponding action potentials (shaded area indicates standard deviation; vertical bar corresponds to 100 μV). Lower panels: raster plot. The 300 ms pre-stimulus baseline was used only for statistics. D. Sagittal view of recording locations for thalamic (squares) and subthalamic (circles) targets (see Figure S3B for a coronal view). Filled circles or squares are sensory-selective neurons. Legend: VL: ventral lateral thalamus, VPlm: ventral posterior lateral and medial thalamus, VPi: ventral posterior inferior thalamus, STN: subthalamic nucleus, SN: substentia nigra, GPi/e: globus pallidus internalis / externalis,

Representative perception-selective neurons in distinct patients.

A-C Upper panels: firing rate time-locked to the onset of the stimulus (100 ms vibrotactile stimulation; blue sinusoid) for hits (light blue) and misses (red). Thick horizontal black segments show significant time windows. Shaded areas indicate bootstrapped standard errors. Inset: corresponding action potentials (shaded area indicates standard deviation; vertical bar corresponds to 100 μV). Lower panels: raster plot for hits (light blue) and misses (red). D. Sagittal view of recording locations for thalamic (squares) and subthalamic (circles) targets (see Figure S3C for a coronal view). Filled circles or squares are perception-selective neurons. Legend: VL: ventral lateral thalamus, VPlm: ventral posterior lateral and medial thalamus, VPi: ventral posterior inferior thalamus, STN: subthalamic nucleus, SN: substentia GPi/e: globus pallidus internalis / externalis,

Neurons from Figure 4, for different stimulus intensities and onsets.

We used the same trials as in Figure 4 but segregated in high versus low stimulus intensities (upper panel) or short and long stimulus onsets (lower panel). We found only 5 / 32 neurons sensitive to stimulus intensity (16%; p = 0.13; permutation test) and no neurons sensitive to stimulus onset (0 / 35). None of the 5 intensity-selective neuron corresponded to a perception-sensitive neuron. A-C. Firing rate time-locked to the onset of the stimulus (100 ms vibrotactile stimulation; blue sinusoid) for high intensity (light blue) and low intensity (dark blue) trials (upper panel) or early (green) and late (orange) stimulus onsets. Shaded areas indicate bootstrapped standard errors. Inset: corresponding action potentials (shaded area indicates standard deviation; vertical bar corresponds to 100 μV).