Neural excitability and sensory input determine intensity perception with opposing directions in initial cortical responses

eLife

Alice Hodapp¹  Arno Villringer²  Vadim V Nikulin³  Tilman Stephani⁴  Mina Jamshidi Idaji⁵ 

[1] Department of Neurology, Max Planck Institute for Human Cognitive and Brain Sciences, Leipzig, Germany;Department of Neurology, Max Planck Institute for Human Cognitive and Brain Sciences, Leipzig, Germany;Berlin School of Mind and Brain, Humboldt-Universität zu Berlin, Berlin, Germany;Clinic for Cognitive Neurology, University Hospital Leipzig, Leipzig, Germany;Department of Neurology, Max Planck Institute for Human Cognitive and Brain Sciences, Leipzig, Germany;Institute for Cognitive Neuroscience, National Research University Higher School of Economics, Moscow, Russian Federation;Department of Neurology, Max Planck Institute for Human Cognitive and Brain Sciences, Leipzig, Germany;International Max Planck Research School NeuroCom, Leipzig, Germany;Department of Neurology, Max Planck Institute for Human Cognitive and Brain Sciences, Leipzig, Germany;International Max Planck Research School NeuroCom, Leipzig, Germany;Machine Learning Group, Technical University of Berlin, Berlin, Germany;

关键词: somatosensory;    EEG;    alpha;    oscillations;    excitability;    intensity perception;    Human;   

DOI  :  10.7554/eLife.67838

来源: eLife Sciences Publications, Ltd

【 摘 要 】

Perception of sensory information is determined by stimulus features (e.g., intensity) and instantaneous neural states (e.g., excitability). Commonly, it is assumed that both are reflected similarly in evoked brain potentials, that is, larger amplitudes are associated with a stronger percept of a stimulus. We tested this assumption in a somatosensory discrimination task in humans, simultaneously assessing (i) single-trial excitatory post-synaptic currents inferred from short-latency somatosensory evoked potentials (SEPs), (ii) pre-stimulus alpha oscillations (8–13 Hz), and (iii) peripheral nerve measures. Fluctuations of neural excitability shaped the perceived stimulus intensity already during the very first cortical response (at ~20 ms) yet demonstrating opposite neural signatures as compared to the effect of presented stimulus intensity. We reconcile this discrepancy via a common framework based on the modulation of electro-chemical membrane gradients linking neural states and responses, which calls for reconsidering conventional interpretations of brain potential magnitudes in stimulus intensity encoding.

【 授权许可】

CC BY