Subcortical correlates of consciousness with human single neuron recordings
Michael Pereira, Nathan Faivre, Fosco Bernasconi, Nicholas Brandmeir, Jacob Suffridge, Kaylee Tran, Shuo Wang, Victor Finomore, Peter Konrad, Ali Rezai, Olaf Blanke
bioRxiv Preprint Server January 27, 2023 preprint DOI: 10.1101/2023.01.27.525684 via bioRxiv
Summary
Neurons in the subthalamic nucleus and thalamus, subcortical brain structures, modulate their activity during expectation of a weak vibrotactile stimulus on the hand, and 23% of these neurons show firing rates that differ between detected and undetected stimuli. This provides direct neurophysiological evidence that these subcortical regions are involved in perceptual consciousness, challenging the prevailing cortico-centric view.
Study at a glance
| Characteristics | Observational cohort |
|---|---|
| Population | Neurological patients undergoing surgery for deep brain stimulation |
| Key finding | The firing rate of 23% of neurons in the subthalamic nucleus and thalamus differed between detected and undetected vibrotactile stimuli. |
Abstract
Subcortical brain structures such as the subthalamic nucleus or the thalamus are involved in regulating motor and cognitive behavior. However, their contribution to perceptual consciousness is still unclear, due to the inherent difficulties of recording subcortical neuronal activity in humans. Here, we asked neurological patients undergoing surgery for deep brain stimulation to detect weak vibrotactile stimuli applied on their hand while recording single neuron activity from the tip of a microelectrode. We isolated putative single neurons in the subthalamic nucleus and thalamus. A significant proportion of neurons modulated their activity while participants were expecting a stimulus. We found that the firing rate of 23% of these neurons differed between detected and undetected stimuli. Our results provide direct neurophysiological evidence of the involvement of the subthalamic nucleus and the thalamus for the detection of vibrotactile stimuli, thereby calling for a less cortico-centric view of the neural correlates of consciousness.