title: Thalamic Responses to Nociceptive-Specific Input in Humans: Functional Dichotomies and Thalamo-Cortical Connectivity.
abstract: While nociceptive cortical activation is now well characterized in humans, understanding of the nociceptive thalamus remains largely fragmentary. We used laser stimuli and intracerebral electrodes in 17 human subjects to record nociceptive-specific field responses in 4 human thalamic nuclei and a number of cortical areas. Three nuclei known to receive spinothalamic (STT) projections in primates (ventro-postero-lateral [VPL], anterior pulvinar [PuA], and central lateral [CL]) exhibited responses with similar latency, indicating their parallel activation by nociceptive afferents. Phase coherence analysis, however, revealed major differences in their functional connectivity: while VPL and PuA drove a limited set of cortical targets, CL activities were synchronized with a large network including temporal, parietal, and frontal areas. Our data suggest that STT afferents reach simultaneously a set of lateral and medial thalamic regions unconstrained by traditional nuclear borders. The broad pattern of associated cortical networks suggests that a single nociceptive volley is able to trigger the sensory, cognitive, and emotional activities that underlie the complex pain experience. The medial pulvinar, an associative nucleus devoid of STT input, exhibited delayed responses suggesting its dependence on descending cortico-thalamic projections. Its widespread cortical connectivity suggests a role in synchronizing parietal, temporal, and frontal activities, hence contributing to the access of noxious input to conscious awareness.
authors.affiliation: Central Integration of Pain (NeuroPain) Lab-Lyon Neuroscience Research Center, INSERM U1028, CNRS, UMR5292, Université Claude Bernard, Bron F-69677, France Unité D'Hypnologie, Service de Neurologie Fonctionnelle et D'Épileptologie, Hôpital Neurologique, Hospices Civils de Lyon, Bron F-69677, France.
authors.forename: Hélène
authors.initials: H
authors.lastname: Bastuji
authors.affiliation: Central Integration of Pain (NeuroPain) Lab-Lyon Neuroscience Research Center, INSERM U1028, CNRS, UMR5292, Université Claude Bernard, Bron F-69677, France.
authors.forename: Maud
authors.initials: M
authors.lastname: Frot
authors.affiliation: Université Lumière Lyon 2, Laboratoire D'Etude des Mécanismes Cognitifs (EMC), Bron F-69676, France.
authors.forename: Stéphanie
authors.initials: S
authors.lastname: Mazza
authors.affiliation: Central Integration of Pain (NeuroPain) Lab-Lyon Neuroscience Research Center, INSERM U1028, CNRS, UMR5292, Université Claude Bernard, Bron F-69677, France.
authors.forename: Caroline
authors.initials: C
authors.lastname: Perchet
authors.affiliation: Central Integration of Pain (NeuroPain) Lab-Lyon Neuroscience Research Center, INSERM U1028, CNRS, UMR5292, Université Claude Bernard, Bron F-69677, France.
authors.forename: Michel
authors.initials: M
authors.lastname: Magnin
authors.affiliation: Central Integration of Pain (NeuroPain) Lab-Lyon Neuroscience Research Center, INSERM U1028, CNRS, UMR5292, Université Claude Bernard, Bron F-69677, France Centre D'évaluation et de Traitement de la Douleur, Hôpital Neurologique, Lyon, France.
authors.forename: Luis
authors.initials: L
authors.lastname: Garcia-Larrea
mesh_terms: D000328:Adult; D002540:Cerebral Cortex / Q000502:physiology*; D000069279:Drug Resistant Epilepsy / Q000188:drug therapy / Q000503:physiopathology / Q000601:surgery; D000069280:Electrocorticography; D004567:Electrodes, Implanted; D005071:Evoked Potentials; D005260:Female; D006801:Humans; D007834:Lasers; D008297:Male; D008875:Middle Aged; D009434:Neural Pathways / Q000502:physiology; D059225:Nociception / Q000502:physiology*; D010812:Physical Stimulation; D013787:Thalamic Nuclei / Q000502:physiology*; D055815:Young Adult
keywords: cortex; human; intracerebral EEG; nociceptive stimulus; thalamus