title: Changes in thalamo-frontal interaction under different levels of anesthesia in rats.
abstract: Anesthesia is thought to be mediated by inhibiting the integration of information between different areas of the brain. Long-range thalamo-cortical interaction plays a critical role in inducing anesthesia-related unconsciousness. However, it remains unclear how this interaction change according to anesthetic depth. In this study, we aimed to investigate how different levels of anesthesia affect thalamo-frontal interactions. Prior to the experiment, electrodes were implanted to record local field potentials (LFPs). Isoflurane (ISO) was administered and LFPs were measured in rats from four different brain areas (left frontal, right frontal, left thalamus and right thalamus) at four different anesthesia levels: awake, deep (ISO 2.5vol%), light (ISO 1vol%) and recovery. Spectral granger causality (Spectral-GC) were calculated at the measured areas in accordance with anesthetic levels. Anesthesia led to a decrease in connectivity in the thalamo-frontal direction and an increase in connectivity in the frontal-thalamic direction. The changes in thalamo-frontal functional connectivity were prominent during deep anesthesia at high frequency bands. The connection strengths between the thalamus and the frontal area changed depending on the depth of anesthesia. The relationships between anesthetic levels and thalamo-frontal activity may shed light on the neural mechanism by which different levels of anesthesia act.
authors.affiliation: Department of Pediatric Dentistry and Dental Research Institute, School of Dentistry, Seoul National University, Seoul, South Korea.
authors.forename: Teo Jeon
authors.initials: TJ
authors.lastname: Shin
authors.affiliation: Department of Biomedical Science and Engineering (BMSE), Gwangju Institute of Science and Technology (GIST), South Korea.
authors.forename: Dongrae
authors.initials: D
authors.lastname: Cho
authors.affiliation: Department of Biomedical Science and Engineering (BMSE), Gwangju Institute of Science and Technology (GIST), South Korea.
authors.forename: Jinsil
authors.initials: J
authors.lastname: Ham
authors.affiliation: Department of Biomedical Science and Engineering (BMSE), Gwangju Institute of Science and Technology (GIST), South Korea.
authors.forename: Dong-Hyuk
authors.initials: DH
authors.lastname: Choi
authors.affiliation: Department of Biomedical Science and Engineering (BMSE), Gwangju Institute of Science and Technology (GIST), South Korea.
authors.forename: Seonghyun
authors.initials: S
authors.lastname: Kim
authors.affiliation: Department of Anesthesiology and Pain Medicine, Chonnam National University Medical School, South Korea.
authors.forename: Seongwook
authors.initials: S
authors.lastname: Jeong
authors.affiliation: Department of Biomedical Science and Engineering (BMSE), Gwangju Institute of Science and Technology (GIST), South Korea.
authors.forename: Hyoung-Ihl
authors.initials: HI
authors.lastname: Kim
authors.affiliation: Department of Biomedical Science and Engineering (BMSE), Gwangju Institute of Science and Technology (GIST), South Korea. Electronic address: jaekim@gist.ac.kr.
authors.forename: Jae Gwan
authors.initials: JG
authors.lastname: Kim
authors.affiliation: Department of Biomedical Science and Engineering (BMSE), Gwangju Institute of Science and Technology (GIST), South Korea. Electronic address: leebr@gist.ac.kr.
authors.forename: Boreom
authors.initials: B
authors.lastname: Lee
mesh_terms: D018685:Anesthetics, Inhalation / Q000008:administration & dosage*; D000818:Animals; D058256:Brain Waves / Q000187:drug effects; D005625:Frontal Lobe / Q000187:drug effects* / Q000502:physiology*; D007530:Isoflurane / Q000008:administration & dosage*; D008297:Male; D051381:Rats; D020318:Rats, Long-Evans; D012815:Signal Processing, Computer-Assisted; D013788:Thalamus / Q000187:drug effects* / Q000502:physiology*
chemical_list: D018685:Anesthetics, Inhalation; D007530:Isoflurane
keywords: Anesthesia; Causality; Consciousness; Isoflurane