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Kawas MI, Atcheson KM, Flood WC, Sheridan CA, Barcus RA, Flashman LA, McAllister TW, Lipford ME, Kim J, Urban JE, Davenport EM, Vaughan CG, Sai KKS, Stitzel JD, Maldjian JA, Whitlow CT. Cognitive and Salience Network Connectivity Changes following a Single Season of Repetitive Head Impact Exposure in High School Football. AJNR Am J Neuroradiol 2024; 45:1116-1123. [PMID: 39054293 PMCID: PMC11383397 DOI: 10.3174/ajnr.a8294] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2024] [Accepted: 03/18/2024] [Indexed: 07/27/2024]
Abstract
BACKGROUND AND PURPOSE During a season of high school football, adolescents with actively developing brains experience a considerable number of head impacts. Our aim was to determine whether repetitive head impacts in the absence of a clinically diagnosed concussion during a season of high school football produce changes in cognitive performance or functional connectivity of the salience network and its central hub, the dorsal anterior cingulate cortex. MATERIALS AND METHODS Football players were instrumented with the Head Impact Telemetry System during all practices and games, and the helmet sensor data were used to compute a risk-weighted exposure metric (RWEcp), accounting for the cumulative risk during the season. Participants underwent MRI and a cognitive battery (ImPACT) before and shortly after the football season. A control group of noncontact/limited-contact-sport athletes was formed from 2 cohorts: one from the same school and protocol and another from a separate, nearly identical study. RESULTS Sixty-three football players and 34 control athletes were included in the cognitive performance analysis. Preseason, the control group scored significantly higher on the ImPACT Visual Motor (P = .04) and Reaction Time composites (P = .006). These differences increased postseason (P = .003, P < .001, respectively). Additionally, the control group had significantly higher postseason scores on the Visual Memory composite (P = .001). Compared with controls, football players showed significantly less improvement in the Verbal (P = .04) and Visual Memory composites (P = .01). A significantly greater percentage of contact athletes had lower-than-expected scores on the Verbal Memory (27% versus 6%), Visual Motor (21% versus 3%), and Reaction Time composites (24% versus 6%). Among football players, a higher RWEcp was significantly associated with greater increments in ImPACT Reaction Time (P = .03) and Total Symptom Scores postseason (P = .006). Fifty-seven football players and 13 control athletes were included in the imaging analyses. Postseason, football players showed significant decreases in interhemispheric connectivity of the dorsal anterior cingulate cortex (P = .026) and within-network connectivity of the salience network (P = .018). These decreases in dorsal anterior cingulate cortex interhemispheric connectivity and within-network connectivity of the salience network were significantly correlated with deteriorating ImPACT Total Symptom (P = .03) and Verbal Memory scores (P = .04). CONCLUSIONS Head impact exposure during a single season of high school football is negatively associated with cognitive performance and brain network connectivity. Future studies should further characterize these short-term effects and examine their relationship with long-term sequelae.
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Affiliation(s)
- Mohammad I Kawas
- From the Department of Radiology (M.I.K., K.M.A., W.C.F., C.A.S., R.A.B., M.E.L., J.K., K.K.S.S., C.T.W.), Wake Forest School of Medicine/Atrium Health Wake Forest Baptist, Winston-Salem, North Carolina
- Department of Physiology (M.I.K.), Faculty of Medicine, University of Jordan, Amman, Jordan
| | - Kyle M Atcheson
- From the Department of Radiology (M.I.K., K.M.A., W.C.F., C.A.S., R.A.B., M.E.L., J.K., K.K.S.S., C.T.W.), Wake Forest School of Medicine/Atrium Health Wake Forest Baptist, Winston-Salem, North Carolina
| | - William C Flood
- From the Department of Radiology (M.I.K., K.M.A., W.C.F., C.A.S., R.A.B., M.E.L., J.K., K.K.S.S., C.T.W.), Wake Forest School of Medicine/Atrium Health Wake Forest Baptist, Winston-Salem, North Carolina
| | - Christopher A Sheridan
- From the Department of Radiology (M.I.K., K.M.A., W.C.F., C.A.S., R.A.B., M.E.L., J.K., K.K.S.S., C.T.W.), Wake Forest School of Medicine/Atrium Health Wake Forest Baptist, Winston-Salem, North Carolina
| | - Richard A Barcus
- From the Department of Radiology (M.I.K., K.M.A., W.C.F., C.A.S., R.A.B., M.E.L., J.K., K.K.S.S., C.T.W.), Wake Forest School of Medicine/Atrium Health Wake Forest Baptist, Winston-Salem, North Carolina
| | - Laura A Flashman
- Department of Neuropsychology (L.A.F.), Wake Forest School of Medicine/Atrium Health Wake Forest Baptist, Winston-Salem, North Carolina
| | - Thomas W McAllister
- Department of Psychiatry (T.W.M.), Indiana University School of Medicine, Indianapolis, Indiana
| | - Megan E Lipford
- From the Department of Radiology (M.I.K., K.M.A., W.C.F., C.A.S., R.A.B., M.E.L., J.K., K.K.S.S., C.T.W.), Wake Forest School of Medicine/Atrium Health Wake Forest Baptist, Winston-Salem, North Carolina
| | - Jeongchul Kim
- From the Department of Radiology (M.I.K., K.M.A., W.C.F., C.A.S., R.A.B., M.E.L., J.K., K.K.S.S., C.T.W.), Wake Forest School of Medicine/Atrium Health Wake Forest Baptist, Winston-Salem, North Carolina
| | - Jillian E Urban
- Department of Biomedical Engineering (J.E.U., J.D.S.), Wake Forest School of Medicine, Winston-Salem, North Carolina
| | - Elizabeth M Davenport
- Department of Radiology (E.M.D., J.A.M), University of Texas Southwestern Medical Center, Dallas, Texas
| | - Christopher G Vaughan
- Division of Pediatric Neuropsychology (C.G.V.), Children's National Hospital, Washington, DC
| | - Kiran K Solingapuram Sai
- From the Department of Radiology (M.I.K., K.M.A., W.C.F., C.A.S., R.A.B., M.E.L., J.K., K.K.S.S., C.T.W.), Wake Forest School of Medicine/Atrium Health Wake Forest Baptist, Winston-Salem, North Carolina
| | - Joel D Stitzel
- Department of Biomedical Engineering (J.E.U., J.D.S.), Wake Forest School of Medicine, Winston-Salem, North Carolina
| | - Joseph A Maldjian
- Department of Radiology (E.M.D., J.A.M), University of Texas Southwestern Medical Center, Dallas, Texas
| | - Christopher T Whitlow
- From the Department of Radiology (M.I.K., K.M.A., W.C.F., C.A.S., R.A.B., M.E.L., J.K., K.K.S.S., C.T.W.), Wake Forest School of Medicine/Atrium Health Wake Forest Baptist, Winston-Salem, North Carolina
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Onicas AI, Deighton S, Yeates KO, Bray S, Graff K, Abdeen N, Beauchamp MH, Beaulieu C, Bjornson B, Craig W, Dehaes M, Deschenes S, Doan Q, Freedman SB, Goodyear BG, Gravel J, Lebel C, Ledoux AA, Zemek R, Ware AL. Longitudinal Functional Connectome in Pediatric Concussion: An Advancing Concussion Assessment in Pediatrics Study. J Neurotrauma 2024; 41:587-603. [PMID: 37489293 DOI: 10.1089/neu.2023.0183] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/26/2023] Open
Abstract
Advanced magnetic resonance imaging (MRI) techniques indicate that concussion (i.e., mild traumatic brain injury) disrupts brain structure and function in children. However, the functional connectivity of brain regions within global and local networks (i.e., functional connectome) is poorly understood in pediatric concussion. This prospective, longitudinal study addressed this gap using data from the largest neuroimaging study of pediatric concussion to date to study the functional connectome longitudinally after concussion as compared with mild orthopedic injury (OI). Children and adolescents (n = 967) 8-16.99 years with concussion or mild OI were recruited from pediatric emergency departments within 48 h post-injury. Pre-injury and 1-month post-injury symptom ratings were used to classify concussion with or without persistent symptoms based on reliable change. Subjects completed a post-acute (2-33 days) and chronic (3 or 6 months via random assignment) MRI scan. Graph theory metrics were derived from 918 resting-state functional MRI scans in 585 children (386 concussion/199 OI). Linear mixed-effects modeling was performed to assess group differences over time, correcting for multiple comparisons. Relative to OI, the global clustering coefficient was reduced at 3 months post-injury in older children with concussion and in females with concussion and persistent symptoms. Time post-injury and sex moderated group differences in local (regional) network metrics of several brain regions, including degree centrality, efficiency, and clustering coefficient of the angular gyrus, calcarine fissure, cuneus, and inferior occipital, lingual, middle occipital, post-central, and superior occipital gyrus. Relative to OI, degree centrality and nodal efficiency were reduced post-acutely, and nodal efficiency and clustering coefficient were reduced chronically after concussion (i.e., at 3 and 6 months post-injury in females; at 6 months post-injury in males). Functional network alterations were more robust and widespread chronically as opposed to post-acutely after concussion, and varied by sex, age, and symptom recovery at 1-month post-injury. Local network segregation reductions emerged globally (across the whole brain network) in older children and in females with poor recovery chronically after concussion. Reduced functioning between neighboring regions could negatively disrupt specialized information processing. Local network metric alterations were demonstrated in several posterior regions that are involved in vision and attention after concussion relative to OI. This indicates that functioning of superior parietal and occipital regions could be particularly susceptibile to the effects of concussion. Moreover, those regional alterations were especially apparent at later time periods post-injury, emerging after post-concussive symptoms resolved in most and persisted up to 6 months post-injury, and differed by biological sex. This indicates that neurobiological changes continue to occur up to 6 months after pediatric concussion, although changes emerge earlier in females than in males. Changes could reflect neural compensation mechanisms.
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Affiliation(s)
- Adrian I Onicas
- MoMiLab, IMT School for Advanced Studies Lucca, Lucca, LU, Italy
- Computer Vision Group, Sano Centre for Computational Medicine, Kraków, Poland. Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada
| | - Stephanie Deighton
- Department of Psychology, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada
| | - Keith Owen Yeates
- Department of Psychology, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada
| | - Signe Bray
- Department of Radiology, Alberta Children's Hospital Research Institute, and Hotchkiss Brain Institute, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada
| | - Kirk Graff
- Department of Radiology, Alberta Children's Hospital Research Institute, and Hotchkiss Brain Institute, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada
| | - Nishard Abdeen
- Department of Radiology, University of Ottawa, and Children's Hospital of Eastern Ontario Research Institute, Ottawa, Ontario, Canada
| | - Miriam H Beauchamp
- Department of Psychology, University of Montreal and CHU Sainte-Justine Hospital Research Center, Montréal, Quebec, Canada
| | - Christian Beaulieu
- Department of Biomedical Engineering, University of Alberta, Edmonton, Alberta, Canada
| | - Bruce Bjornson
- Division of Neurology, University of British Columbia, BC Children's Hospital Research Institute, Vancouver, British Columbia, Canada
| | - William Craig
- University of Alberta and Stollery Children's Hospital, Edmonton, Alberta, Canada
| | - Mathieu Dehaes
- Department of Radiology, Radio-oncology and Nuclear Medicine, Institute of Biomedical Engineering, University of Montreal and CHU Sainte-Justine Hospital Research Center, Montréal, Quebec, Canada
| | - Sylvain Deschenes
- Department of Radiology, Radio-oncology and Nuclear Medicine, Institute of Biomedical Engineering, University of Montreal and CHU Sainte-Justine Hospital Research Center, Montréal, Quebec, Canada
| | - Quynh Doan
- Department of Pediatrics, University of British Columbia, BC Children's Hospital Research Institute, Vancouver, British Columbia, Canada
| | - Stephen B Freedman
- Departments of Pediatric and Emergency Medicine, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada
| | - Bradley G Goodyear
- Department of Radiology, Alberta Children's Hospital Research Institute, and Hotchkiss Brain Institute, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada
| | - Jocelyn Gravel
- Department of Department of Pediatric Emergency Medicine, University of Montreal and CHU Sainte-Justine Hospital Research Center, Montréal, Quebec, Canada
| | - Catherine Lebel
- Department of Radiology, Alberta Children's Hospital Research Institute, and Hotchkiss Brain Institute, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada
| | - Andrée-Anne Ledoux
- Department of Cellular and Molecular Medicine, University of Ottawa, and Children's Hospital of Eastern Ontario Research Institute, Ottawa, Ontario, Canada
| | - Roger Zemek
- Department of Pediatrics and Emergency Medicine, University of Ottawa, and Children's Hospital of Eastern Ontario Research Institute, Ottawa, Ontario, Canada
| | - Ashley L Ware
- Department of Psychology, Georgia State University, Atlanta, Georgia, USA, and Department of Neurology, University of Utah, Salt Lake City, Utah, USA
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McLeod J, Chavan A, Lee H, Sattari S, Kurry S, Wake M, Janmohamed Z, Hodges NJ, Virji-Babul N. Distinct Effects of Brain Activation Using tDCS and Observational Practice: Implications for Motor Rehabilitation. Brain Sci 2024; 14:175. [PMID: 38391749 PMCID: PMC10886768 DOI: 10.3390/brainsci14020175] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2024] [Revised: 02/06/2024] [Accepted: 02/08/2024] [Indexed: 02/24/2024] Open
Abstract
Complex motor skills can be acquired while observing a model without physical practice. Transcranial direct-current stimulation (tDCS) applied to the primary motor cortex (M1) also facilitates motor learning. However, the effectiveness of observational practice for bimanual coordination skills is debated. We compared the behavioural and brain causal connectivity patterns following three interventions: primary motor cortex stimulation (M1-tDCS), action-observation (AO) and a combined group (AO+M1-tDCS) when acquiring a bimanual, two-ball juggling skill. Thirty healthy young adults with no juggling experience were randomly assigned to either video observation of a skilled juggler, anodal M1-tDCS or video observation combined with M1-tDCS. Thirty trials of juggling were performed and scored after the intervention. Resting-state EEG data were collected before and after the intervention. Information flow rate was applied to EEG source data to measure causal connectivity. The two observation groups were more accurate than the tDCS alone group. In the AO condition, there was strong information exchange from (L) parietal to (R) parietal regions, strong bidirectional information exchange between (R) parietal and (R) occipital regions and an extensive network of activity that was (L) lateralized. The M1-tDCS condition was characterized by bilateral long-range connections with the strongest information exchange from the (R) occipital region to the (R) temporal and (L) occipital regions. AO+M1-tDCS induced strong bidirectional information exchange in occipital and temporal regions in both hemispheres. Uniquely, it was the only condition that was characterized by information exchange between the (R) frontal and central regions. This study provides new results about the distinct network dynamics of stimulating the brain for skill acquisition, providing insights for motor rehabilitation.
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Affiliation(s)
- Julianne McLeod
- Rehabilitation Science, Faculty of Medicine, University of British Columbia, Vancouver, BC V6T 1Z3, Canada
| | - Anuj Chavan
- Electronics and Telecommunication Engineering, Sardar Patel Institute of Technology, Mumbai 400058, India
| | - Harvey Lee
- Schulich School of Medicine & Dentistry, Western University, London, ON N6A 5C1, Canada
| | - Sahar Sattari
- Biomedical Engineering, Faculty of Applied Science and Faculty of Medicine, University of British Columbia, Vancouver, BC V6T 2B9, Canada
| | - Simrut Kurry
- Neuroscience, Faculty of Science, University of British Columbia, Vancouver, BC V6T 1Z3, Canada
| | - Miku Wake
- Neuroscience, Faculty of Science, University of British Columbia, Vancouver, BC V6T 1Z3, Canada
| | - Zia Janmohamed
- Neuroscience, Faculty of Science, McGill University, Montreal, QC H3A 2B4, Canada
| | - Nicola Jane Hodges
- School of Kinesiology, Faculty of Education, University of British Columbia, Vancouver, BC V6T 1Z1, Canada
| | - Naznin Virji-Babul
- Physical Therapy, Faculty of Medicine, University of British Columbia, Vancouver, BC V6T 1Z3, Canada
- Djavad Mowafaghian Centre for Brain Health, Vancouver, BC V6T 1Z3, Canada
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4
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Burma JS, Lapointe AP, Wilson M, Penner LC, Kennedy CM, Newel KT, Galea OA, Miutz LN, Dunn JF, Smirl JD. Adolescent Sport-Related Concussion and the Associated Neurophysiological Changes: A Systematic Review. Pediatr Neurol 2024; 150:97-106. [PMID: 38006666 DOI: 10.1016/j.pediatrneurol.2023.10.020] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/01/2022] [Revised: 06/20/2023] [Accepted: 10/28/2023] [Indexed: 11/27/2023]
Abstract
BACKGROUND Sport-related concussion (SRC) has been shown to induce cerebral neurophysiological deficits, quantifiable with electroencephalography (EEG). As the adolescent brain is undergoing rapid neurodevelopment, it is fundamental to understand both the short- and long-term ramifications SRC may have on neuronal functioning. The current systematic review sought to amalgamate the literature regarding both acute/subacute (≤28 days) and chronic (>28 days) effects of SRC in adolescents via EEG and the diagnostic accuracy of this tool. METHODS The review was registered within the Prospero database (CRD42021275256). Search strategies were created and input into the PubMed database, where three authors completed all screening. Risk of bias assessments were completed using the Scottish Intercollegiate Guideline Network and Methodological Index for Non-Randomized Studies. RESULTS A total of 128 articles were identified; however, only seven satisfied all inclusion criteria. The studies ranged from 2012 to 2021 and included sample sizes of 21 to 81 participants, albeit only ∼14% of the included athletes were females. The studies displayed low-to-high levels of bias due to the small sample sizes and preliminary nature of most investigations. Although heterogeneous methods, tasks, and analytical techniques were used, 86% of the studies found differences compared with control athletes, in both the symptomatic and asymptomatic phases of SRC. One study used raw EEG data as a diagnostic indicator demonstrating promise; however, more research and standardization are a necessity. CONCLUSIONS Collectively, the findings highlight the utility of EEG in assessing adolescent SRC; however, future studies should consider important covariates including biological sex, maturation status, and development.
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Affiliation(s)
- Joel S Burma
- Cerebrovascular Concussion Lab, Faculty of Kinesiology, University of Calgary, Calgary, Alberta, Canada; Sport Injury Prevention Research Centre, Faculty of Kinesiology, University of Calgary, Calgary, Alberta, Canada; Human Performance Laboratory, Faculty of Kinesiology, University of Calgary, Calgary, Alberta, Canada; Libin Cardiovascular Institute of Alberta, University of Calgary, Calgary, Alberta, Canada; Alberta Children's Hospital Research Institute, University of Calgary, Calgary, Alberta, Canada; Hotchkiss Brain Institute, University of Calgary, Calgary, Alberta, Canada; Integrated Concussion Research Program, University of Calgary, Calgary, Alberta, Canada.
| | - Andrew P Lapointe
- Hotchkiss Brain Institute, University of Calgary, Calgary, Alberta, Canada; Integrated Concussion Research Program, University of Calgary, Calgary, Alberta, Canada; Department of Radiology, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada; Department of Clinical Neurosciences, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada
| | - Megan Wilson
- Faculty of Arts and Social Sciences, Carleton University, Ottawa, Ontario, Canada; Faculty of Arts, University of Alberta, Edmonton, Alberta, Canada
| | - Linden C Penner
- Cerebrovascular Concussion Lab, Faculty of Kinesiology, University of Calgary, Calgary, Alberta, Canada; Sport Injury Prevention Research Centre, Faculty of Kinesiology, University of Calgary, Calgary, Alberta, Canada; Human Performance Laboratory, Faculty of Kinesiology, University of Calgary, Calgary, Alberta, Canada; Libin Cardiovascular Institute of Alberta, University of Calgary, Calgary, Alberta, Canada; Alberta Children's Hospital Research Institute, University of Calgary, Calgary, Alberta, Canada; Hotchkiss Brain Institute, University of Calgary, Calgary, Alberta, Canada; Integrated Concussion Research Program, University of Calgary, Calgary, Alberta, Canada
| | - Courtney M Kennedy
- Cerebrovascular Concussion Lab, Faculty of Kinesiology, University of Calgary, Calgary, Alberta, Canada; Sport Injury Prevention Research Centre, Faculty of Kinesiology, University of Calgary, Calgary, Alberta, Canada; Human Performance Laboratory, Faculty of Kinesiology, University of Calgary, Calgary, Alberta, Canada; Libin Cardiovascular Institute of Alberta, University of Calgary, Calgary, Alberta, Canada; Alberta Children's Hospital Research Institute, University of Calgary, Calgary, Alberta, Canada; Hotchkiss Brain Institute, University of Calgary, Calgary, Alberta, Canada; Integrated Concussion Research Program, University of Calgary, Calgary, Alberta, Canada
| | - Kailey T Newel
- Cerebrovascular Concussion Lab, Faculty of Kinesiology, University of Calgary, Calgary, Alberta, Canada; Sport Injury Prevention Research Centre, Faculty of Kinesiology, University of Calgary, Calgary, Alberta, Canada; Integrated Concussion Research Program, University of Calgary, Calgary, Alberta, Canada; Faculty of Health and Exercise Science, University of British Columbia, Kelowna, British Columbia, Canada
| | - Olivia A Galea
- Cerebrovascular Concussion Lab, Faculty of Kinesiology, University of Calgary, Calgary, Alberta, Canada; Sport Injury Prevention Research Centre, Faculty of Kinesiology, University of Calgary, Calgary, Alberta, Canada; Human Performance Laboratory, Faculty of Kinesiology, University of Calgary, Calgary, Alberta, Canada; Libin Cardiovascular Institute of Alberta, University of Calgary, Calgary, Alberta, Canada; Alberta Children's Hospital Research Institute, University of Calgary, Calgary, Alberta, Canada; Hotchkiss Brain Institute, University of Calgary, Calgary, Alberta, Canada; Integrated Concussion Research Program, University of Calgary, Calgary, Alberta, Canada
| | - Lauren N Miutz
- Cerebrovascular Concussion Lab, Faculty of Kinesiology, University of Calgary, Calgary, Alberta, Canada; Sport Injury Prevention Research Centre, Faculty of Kinesiology, University of Calgary, Calgary, Alberta, Canada; Human Performance Laboratory, Faculty of Kinesiology, University of Calgary, Calgary, Alberta, Canada; Libin Cardiovascular Institute of Alberta, University of Calgary, Calgary, Alberta, Canada; Alberta Children's Hospital Research Institute, University of Calgary, Calgary, Alberta, Canada; Hotchkiss Brain Institute, University of Calgary, Calgary, Alberta, Canada; Integrated Concussion Research Program, University of Calgary, Calgary, Alberta, Canada
| | - Jeff F Dunn
- Alberta Children's Hospital Research Institute, University of Calgary, Calgary, Alberta, Canada; Hotchkiss Brain Institute, University of Calgary, Calgary, Alberta, Canada; Integrated Concussion Research Program, University of Calgary, Calgary, Alberta, Canada; Department of Radiology, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada; Department of Clinical Neurosciences, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada
| | - Jonathan D Smirl
- Cerebrovascular Concussion Lab, Faculty of Kinesiology, University of Calgary, Calgary, Alberta, Canada; Sport Injury Prevention Research Centre, Faculty of Kinesiology, University of Calgary, Calgary, Alberta, Canada; Human Performance Laboratory, Faculty of Kinesiology, University of Calgary, Calgary, Alberta, Canada; Libin Cardiovascular Institute of Alberta, University of Calgary, Calgary, Alberta, Canada; Alberta Children's Hospital Research Institute, University of Calgary, Calgary, Alberta, Canada; Hotchkiss Brain Institute, University of Calgary, Calgary, Alberta, Canada; Integrated Concussion Research Program, University of Calgary, Calgary, Alberta, Canada
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Sattari S, Kenny R, Liu CC, Hajra SG, Dumont GA, Virji-Babul N. Blink-related EEG oscillations are neurophysiological indicators of subconcussive head impacts in female soccer players: a preliminary study. Front Hum Neurosci 2023; 17:1208498. [PMID: 37538402 PMCID: PMC10394644 DOI: 10.3389/fnhum.2023.1208498] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2023] [Accepted: 07/03/2023] [Indexed: 08/05/2023] Open
Abstract
Introduction Repetitive subconcussive head impacts can lead to subtle neural changes and functional consequences on brain health. However, the objective assessment of these changes remains limited. Resting state blink-related oscillations (BROs), recently discovered neurological responses following spontaneous blinking, are explored in this study to evaluate changes in BRO responses in subconcussive head impacts. Methods We collected 5-min resting-state electroencephalography (EEG) data from two cohorts of collegiate athletes who were engaged in contact sports (SC) or non-contact sports (HC). Video recordings of all on-field activities were conducted to determine the number of head impacts during games and practices in the SC group. Results In both groups, we were able to detect a BRO response. Following one season of games and practice, we found a strong association between the number of head impacts sustained by the SC group and increases in delta and beta spectral power post-blink. There was also a significant difference between the two groups in the morphology of BRO responses, including decreased peak-to-peak amplitude of response over left parietal channels and differences in spectral power in delta and alpha frequency range post-blink. Discussion Our preliminary results suggest that the BRO response may be a useful biomarker for detecting subtle neural changes resulting from repetitive head impacts. The clinical utility of this biomarker will need to be validated through further research with larger sample sizes, involving both male and female participants, using a longitudinal design.
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Affiliation(s)
- Sahar Sattari
- School of Biomedical Engineering, The University of British Columbia, Vancouver, BC, Canada
| | - Rebecca Kenny
- Department of Rehabilitation Sciences, The University of British Columbia, Vancouver, BC, Canada
| | - Careesa Chang Liu
- Department of Biomedical Engineering and Science, Florida Institute of Technology, Melbourne, FL, United States
| | - Sujoy Ghosh Hajra
- Department of Biomedical Engineering and Science, Florida Institute of Technology, Melbourne, FL, United States
| | - Guy A. Dumont
- School of Biomedical Engineering, The University of British Columbia, Vancouver, BC, Canada
- Department of Electrical and Computer Engineering, The University of British Columbia, Vancouver, BC, Canada
- BC Children’s Hospital Research Institute, Vancouver, BC, Canada
| | - Naznin Virji-Babul
- Department of Rehabilitation Sciences, The University of British Columbia, Vancouver, BC, Canada
- Department of Physical Therapy, Djavad Mowafaghian Centre for Brain Health, The University of British Columbia, Vancouver, BC, Canada
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Cong J, Zhuang W, Liu Y, Yin S, Jia H, Yi C, Chen K, Xue K, Li F, Yao D, Xu P, Zhang T. Altered default mode network causal connectivity patterns in autism spectrum disorder revealed by Liang information flow analysis. Hum Brain Mapp 2023; 44:2279-2293. [PMID: 36661190 PMCID: PMC10028659 DOI: 10.1002/hbm.26209] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2022] [Revised: 12/26/2022] [Accepted: 01/05/2023] [Indexed: 01/21/2023] Open
Abstract
Autism spectrum disorder (ASD) is a pervasive developmental disorder with severe cognitive impairment in social communication and interaction. Previous studies have reported that abnormal functional connectivity patterns within the default mode network (DMN) were associated with social dysfunction in ASD. However, how the altered causal connectivity pattern within the DMN affects the social functioning in ASD remains largely unclear. Here, we introduced the Liang information flow method, widely applied to climate science and quantum mechanics, to uncover the brain causal network patterns in ASD. Compared with the healthy controls (HC), we observed that the interactions among the dorsal medial prefrontal cortex (dMPFC), ventral medial prefrontal cortex (vMPFC), hippocampal formation, and temporo-parietal junction showed more inter-regional causal connectivity differences in ASD. For the topological property analysis, we also found the clustering coefficient of DMN and the In-Out degree of anterior medial prefrontal cortex were significantly decreased in ASD. Furthermore, we found that the causal connectivity from dMPFC to vMPFC was correlated with the clinical symptoms of ASD. These altered causal connectivity patterns indicated that the DMN inter-regions information processing was perturbed in ASD. In particular, we found that the dMPFC acts as a causal source in the DMN in HC, whereas it plays a causal target in ASD. Overall, our findings indicated that the Liang information flow method could serve as an important way to explore the DMN causal connectivity patterns, and it also can provide novel insights into the nueromechanisms underlying DMN dysfunction in ASD.
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Affiliation(s)
- Jing Cong
- Mental Health Education Center and School of Science, Xihua University, Chengdu, China
| | - Wenwen Zhuang
- Mental Health Education Center and School of Science, Xihua University, Chengdu, China
| | - Yunhong Liu
- Mental Health Education Center and School of Science, Xihua University, Chengdu, China
| | - Shunjie Yin
- Mental Health Education Center and School of Science, Xihua University, Chengdu, China
| | - Hai Jia
- Mental Health Education Center and School of Science, Xihua University, Chengdu, China
| | - Chanlin Yi
- The Clinical Hospital of Chengdu Brain Science Institute, MOE Key Lab for Neuroinformation, University of Electronic Science and Technology of China, Chengdu, China
| | - Kai Chen
- Mental Health Education Center and School of Science, Xihua University, Chengdu, China
| | - Kaiqing Xue
- School of Computer and Software Engineering, Xihua University, Chengdu, China
| | - Fali Li
- The Clinical Hospital of Chengdu Brain Science Institute, MOE Key Lab for Neuroinformation, University of Electronic Science and Technology of China, Chengdu, China
| | - Dezhong Yao
- The Clinical Hospital of Chengdu Brain Science Institute, MOE Key Lab for Neuroinformation, University of Electronic Science and Technology of China, Chengdu, China
| | - Peng Xu
- The Clinical Hospital of Chengdu Brain Science Institute, MOE Key Lab for Neuroinformation, University of Electronic Science and Technology of China, Chengdu, China
| | - Tao Zhang
- Mental Health Education Center and School of Science, Xihua University, Chengdu, China
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Lu X, Liu K, Liang XS, Lai KK, Cui H. The dynamic causality in sporadic bursts between CO 2 emission allowance prices and clean energy index. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2022; 29:77724-77736. [PMID: 35687289 PMCID: PMC9186288 DOI: 10.1007/s11356-022-21316-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/12/2021] [Accepted: 06/02/2022] [Indexed: 06/15/2023]
Abstract
This study examines the dynamic causality between the carbon emission market and the clean energy market, using an information flow-based, quantitative Liang causality analysis which is firmly grounded on physics and derived from first principles. The dynamic causal relationships between European Union Allowance (EUA) prices and clean energy index allow us to explore whether the causality in return or in variance from CO2 emission allowances to the clean energy index is time-varying. The results show that the causal relationships in return and in variance between EUA and Clean Energy Index (CEI) are drastically time-varying. For the causality in return, a significant unidirectional long-term and stable causality from CEI to EUA is identified after March 2020. For that in variance, a bidirectional causality is found after March 2020, but values after 2020 are opposite to those in return. It seems when fluctuations in the clean energy market are low, the clean energy market has a weak causal effect on the carbon emission market but when volatility in the clean energy market is increasing, causalities between the two markets are significantly strengthened. These results obtained through this rigorous causality analysis can serve as a reference for academics, market participants, and policymakers to understand the underlying links between EUA prices and clean energy index.
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Affiliation(s)
- Xunfa Lu
- School of Management Science and Engineering, Nanjing University of Information Science and Technology, No. 219, Ningliu Road, Pukou District, Nanjing, 210044 China
| | - Kai Liu
- Center for Economics, Finance and Management Studies, Hunan University, Changsha, 410006 China
| | | | - Kin Keung Lai
- International Business School, Shaanxi Normal University, Xi’an, 710062 China
| | - Hairong Cui
- School of Management Science and Engineering, Nanjing University of Information Science and Technology, No. 219, Ningliu Road, Pukou District, Nanjing, 210044 China
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8
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Yi B, Bose S. Quantum Liang Information Flow as Causation Quantifier. PHYSICAL REVIEW LETTERS 2022; 129:020501. [PMID: 35867429 DOI: 10.1103/physrevlett.129.020501] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/30/2022] [Accepted: 06/22/2022] [Indexed: 06/15/2023]
Abstract
Liang information flow is widely used in classical systems and network theory for causality quantification and has been applied widely, for example, to finance, neuroscience, and climate studies. The key part of the theory is to freeze a node of a network to ascertain its causal influence on other nodes. Such a theory is yet to be applied to quantum network dynamics. Here, we generalize the Liang information flow to the quantum domain with respect to von Neumann entropy and exemplify its usage by applying it to a variety of small quantum networks.
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Affiliation(s)
- Bin Yi
- Department of Physics and Astronomy, University College London, Gower Street, WC1E 6BT London, United Kingdom
| | - Sougato Bose
- Department of Physics and Astronomy, University College London, Gower Street, WC1E 6BT London, United Kingdom
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9
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Thanjavur K, Hristopulos DT, Babul A, Yi KM, Virji-Babul N. Deep Learning Recurrent Neural Network for Concussion Classification in Adolescents Using Raw Electroencephalography Signals: Toward a Minimal Number of Sensors. Front Hum Neurosci 2021; 15:734501. [PMID: 34899212 PMCID: PMC8654150 DOI: 10.3389/fnhum.2021.734501] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2021] [Accepted: 11/01/2021] [Indexed: 11/13/2022] Open
Abstract
Artificial neural networks (ANNs) are showing increasing promise as decision support tools in medicine and particularly in neuroscience and neuroimaging. Recently, there has been increasing work on using neural networks to classify individuals with concussion using electroencephalography (EEG) data. However, to date the need for research grade equipment has limited the applications to clinical environments. We recently developed a deep learning long short-term memory (LSTM) based recurrent neural network to classify concussion using raw, resting state data using 64 EEG channels and achieved high accuracy in classifying concussion. Here, we report on our efforts to develop a clinically practical system using a minimal subset of EEG sensors. EEG data from 23 athletes who had suffered a sport-related concussion and 35 non-concussed, control athletes were used for this study. We tested and ranked each of the original 64 channels based on its contribution toward the concussion classification performed by the original LSTM network. The top scoring channels were used to train and test a network with the same architecture as the previously trained network. We found that with only six of the top scoring channels the classifier identified concussions with an accuracy of 94%. These results show that it is possible to classify concussion using raw, resting state data from a small number of EEG sensors, constituting a first step toward developing portable, easy to use EEG systems that can be used in a clinical setting.
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Affiliation(s)
- Karun Thanjavur
- Department of Physics and Astronomy, University of Victoria, Victoria, BC, Canada
| | | | - Arif Babul
- Department of Physics and Astronomy, University of Victoria, Victoria, BC, Canada
| | - Kwang Moo Yi
- Department of Computer Science, University of British Columbia, Vancouver, BC, Canada
| | - Naznin Virji-Babul
- Djavad Mowafaghian Centre for Brain Health, University of British Columbia, Vancouver, BC, Canada.,Department of Physical Therapy, Faculty of Medicine, University of British Columbia, Vancouver, BC, Canada
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10
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Reddy DD, Davenport EM, Yu FF, Wagner B, Urban JE, Whitlow CT, Stitzel JD, Maldjian JA. Alterations in the Magnetoencephalography Default Mode Effective Connectivity following Concussion. AJNR Am J Neuroradiol 2021; 42:1776-1782. [PMID: 34503943 DOI: 10.3174/ajnr.a7232] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2020] [Accepted: 05/05/2021] [Indexed: 11/07/2022]
Abstract
BACKGROUND AND PURPOSE Magnetoencephalography is sensitive to functional connectivity changes associated with concussion. However, the directional influences between functionally related regions remain unexplored. In this study, we therefore evaluated concussion-related magnetoencephalography-based effective connectivity changes within resting-state default mode network regions. MATERIALS AND METHODS Resting-state magnetoencephalography was acquired for 8 high school football players with concussion at 3 time points (preseason, postconcussion, postseason), as well as 8 high school football players without concussion and 8 age-matched controls at 2 time points (preseason, postseason). Time-series from the default mode network regions were extracted, and effective connectivity between them was computed for 5 different frequency bands. The default mode network regions were grouped into anterior and posterior default mode networks. The combined posterior-to-anterior and anterior-to-posterior effective connectivity values were averaged to generate 2 sets of values for each subject. The effective connectivity values were compared using a repeated measures ANOVA across time points for the concussed, nonconcussed, and control groups, separately. RESULTS A significant increase in posterior-to-anterior effective connectivity from preseason to postconcussion (corrected P value = .013) and a significant decrease in posterior-to-anterior effective connectivity from postconcussion to postseason (corrected P value = .028) were observed in the concussed group. Changes in effective connectivity were only significant within the delta band. Anterior-to-posterior connectivity demonstrated no significant change. Effective connectivity in the nonconcussed group and controls did not show significant differences. CONCLUSIONS The unidirectional increase in effective connectivity postconcussion may elucidate compensatory processes, invoking use of posterior regions to aid the function of susceptible anterior regions following brain injury. These findings support the potential value of magnetoencephalography in exploring directional changes of the brain network following concussion.
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Affiliation(s)
- D D Reddy
- From the Department of Radiology (D.D.R., E.M.D., F.F.Y., B.W., J.A.M.), University of Texas Southwestern, Dallas, Texas
| | - E M Davenport
- From the Department of Radiology (D.D.R., E.M.D., F.F.Y., B.W., J.A.M.), University of Texas Southwestern, Dallas, Texas
| | - F F Yu
- From the Department of Radiology (D.D.R., E.M.D., F.F.Y., B.W., J.A.M.), University of Texas Southwestern, Dallas, Texas
| | - B Wagner
- From the Department of Radiology (D.D.R., E.M.D., F.F.Y., B.W., J.A.M.), University of Texas Southwestern, Dallas, Texas
| | - J E Urban
- Wake Forest School of Medicine (J.E.U. C.T.W., J.D.S.), Winston-Salem, North Carolina
| | - C T Whitlow
- Wake Forest School of Medicine (J.E.U. C.T.W., J.D.S.), Winston-Salem, North Carolina
| | - J D Stitzel
- Wake Forest School of Medicine (J.E.U. C.T.W., J.D.S.), Winston-Salem, North Carolina
| | - J A Maldjian
- From the Department of Radiology (D.D.R., E.M.D., F.F.Y., B.W., J.A.M.), University of Texas Southwestern, Dallas, Texas
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11
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El Niño Modoki can be mostly predicted more than 10 years ahead of time. Sci Rep 2021; 11:17860. [PMID: 34504151 PMCID: PMC8429568 DOI: 10.1038/s41598-021-97111-y] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2020] [Accepted: 08/20/2021] [Indexed: 11/09/2022] Open
Abstract
The 2014-2015 "Monster"/"Super" El Niño failed to be predicted one year earlier due to the growing importance of a new type of El Niño, El Niño Modoki, which reportedly has much lower forecast skill with the classical models. In this study, we show that, so far as of today, this new El Niño actually can be mostly predicted at a lead time of more than 10 years. This is achieved through tracing the predictability source with an information flow-based causality analysis, which has been rigorously established from first principles during the past 16 years (e.g., Liang in Phys Rev E 94:052201, 2016). We show that the information flowing from the solar activity 45 years ago to the sea surface temperature results in a causal structure resembling the El Niño Modoki mode. Based on this, a multidimensional system is constructed out of the sunspot number series with time delays of 22-50 years. The first 25 principal components are then taken as the predictors to fulfill the prediction, which through causal AI based on the Liang-Kleeman information flow reproduces rather accurately the events thus far 12 years in advance.
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12
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Thanjavur K, Babul A, Foran B, Bielecki M, Gilchrist A, Hristopulos DT, Brucar LR, Virji-Babul N. Recurrent neural network-based acute concussion classifier using raw resting state EEG data. Sci Rep 2021; 11:12353. [PMID: 34117309 PMCID: PMC8196170 DOI: 10.1038/s41598-021-91614-4] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2020] [Accepted: 05/24/2021] [Indexed: 02/05/2023] Open
Abstract
Concussion is a global health concern. Despite its high prevalence, a sound understanding of the mechanisms underlying this type of diffuse brain injury remains elusive. It is, however, well established that concussions cause significant functional deficits; that children and youths are disproportionately affected and have longer recovery time than adults; and that individuals suffering from a concussion are more prone to experience additional concussions, with each successive injury increasing the risk of long term neurological and mental health complications. Currently, the most significant challenge in concussion management is the lack of objective, clinically- accepted, brain-based approaches for determining whether an athlete has suffered a concussion. Here, we report on our efforts to address this challenge. Specifically, we introduce a deep learning long short-term memory (LSTM)-based recurrent neural network that is able to distinguish between non-concussed and acute post-concussed adolescent athletes using only short (i.e. 90 s long) samples of resting state EEG data as input. The athletes were neither required to perform a specific task nor expected to respond to a stimulus during data collection. The acquired EEG data were neither filtered, cleaned of artefacts, nor subjected to explicit feature extraction. The LSTM network was trained and validated using data from 27 male, adolescent athletes with sports related concussion, benchmarked against 35 non-concussed adolescent athletes. During rigorous testing, the classifier consistently identified concussions with an accuracy of > 90% and achieved an ensemble median Area Under the Receiver Operating Characteristic Curve (ROC/AUC) equal to 0.971. This is the first instance of a high-performing classifier that relies only on easy-to-acquire resting state, raw EEG data. Our concussion classifier represents a promising first step towards the development of an easy-to-use, objective, brain-based, automatic classification of concussion at an individual level.
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Affiliation(s)
- Karun Thanjavur
- Department of Physics and Astronomy, University of Victoria, Victoria, BC, V8P 5C2, Canada.
| | - Arif Babul
- Department of Physics and Astronomy, University of Victoria, Victoria, BC, V8P 5C2, Canada
| | - Brandon Foran
- Department of Computer Science, Middlesex College, Western University, London, ON, N6A 5B7, Canada
| | - Maya Bielecki
- Department of Computer Science, Middlesex College, Western University, London, ON, N6A 5B7, Canada
| | - Adam Gilchrist
- Department of Computer Science, Middlesex College, Western University, London, ON, N6A 5B7, Canada
| | - Dionissios T Hristopulos
- School of Electrical and Computer Engineering, Technical University of Crete, 73100, Chania, Greece
| | - Leyla R Brucar
- Djavad Mowafaghian Centre for Brain Health, University of British Columbia, Vancouver, BC, V6T 1Z3, Canada
| | - Naznin Virji-Babul
- Djavad Mowafaghian Centre for Brain Health, University of British Columbia, Vancouver, BC, V6T 1Z3, Canada
- Department of Physical Therapy, Faculty of Medicine, University of British Columbia, Vancouver, BC, V6T 1Z3, Canada
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13
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Liang XS. Normalized Multivariate Time Series Causality Analysis and Causal Graph Reconstruction. ENTROPY 2021; 23:e23060679. [PMID: 34071323 PMCID: PMC8228659 DOI: 10.3390/e23060679] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/23/2021] [Revised: 05/13/2021] [Accepted: 05/18/2021] [Indexed: 01/02/2023]
Abstract
Causality analysis is an important problem lying at the heart of science, and is of particular importance in data science and machine learning. An endeavor during the past 16 years viewing causality as a real physical notion so as to formulate it from first principles, however, seems to have gone unnoticed. This study introduces to the community this line of work, with a long-due generalization of the information flow-based bivariate time series causal inference to multivariate series, based on the recent advance in theoretical development. The resulting formula is transparent, and can be implemented as a computationally very efficient algorithm for application. It can be normalized and tested for statistical significance. Different from the previous work along this line where only information flows are estimated, here an algorithm is also implemented to quantify the influence of a unit to itself. While this forms a challenge in some causal inferences, here it comes naturally, and hence the identification of self-loops in a causal graph is fulfilled automatically as the causalities along edges are inferred. To demonstrate the power of the approach, presented here are two applications in extreme situations. The first is a network of multivariate processes buried in heavy noises (with the noise-to-signal ratio exceeding 100), and the second a network with nearly synchronized chaotic oscillators. In both graphs, confounding processes exist. While it seems to be a challenge to reconstruct from given series these causal graphs, an easy application of the algorithm immediately reveals the desideratum. Particularly, the confounding processes have been accurately differentiated. Considering the surge of interest in the community, this study is very timely.
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Affiliation(s)
- X. San Liang
- Nanjing Institute of Meteorology, Nanjing 210044, China;
- Shanghai Qizhi (Andrew C. Yao) Institute, Shanghai 200030, China
- China Institute for Advanced Study, Central University of Finance and Economics, Beijing 100081, China
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14
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A Note on Causation versus Correlation in an Extreme Situation. ENTROPY 2021; 23:e23030316. [PMID: 33799929 PMCID: PMC8001367 DOI: 10.3390/e23030316] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 02/10/2021] [Revised: 03/02/2021] [Accepted: 03/04/2021] [Indexed: 11/16/2022]
Abstract
Recently, it has been shown that the information flow and causality between two time series can be inferred in a rigorous and quantitative sense, and, besides, the resulting causality can be normalized. A corollary that follows is, in the linear limit, causation implies correlation, while correlation does not imply causation. Now suppose there is an event A taking a harmonic form (sine/cosine), and it generates through some process another event B so that B always lags A by a phase of π/2. Here the causality is obviously seen, while by computation the correlation is, however, zero. This apparent contradiction is rooted in the fact that a harmonic system always leaves a single point on the Poincaré section; it does not add information. That is to say, though the absolute information flow from A to B is zero, i.e., TA→B=0, the total information increase of B is also zero, so the normalized TA→B, denoted as τA→B, takes the form of 00. By slightly perturbing the system with some noise, solving a stochastic differential equation, and letting the perturbation go to zero, it can be shown that τA→B approaches 100%, just as one would have expected.
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15
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Sergio LE, Gorbet DJ, Adams MS, Dobney DM. The Effects of Mild Traumatic Brain Injury on Cognitive-Motor Integration for Skilled Performance. Front Neurol 2020; 11:541630. [PMID: 33041992 PMCID: PMC7525090 DOI: 10.3389/fneur.2020.541630] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2020] [Accepted: 08/12/2020] [Indexed: 01/01/2023] Open
Abstract
Adults exposed to blast and blunt impact often experience mild traumatic brain injury, affecting neural functions related to sensory, cognitive, and motor function. In this perspective article, we will review the effects of impact and blast exposure on functional performance that requires the integration of these sensory, cognitive, and motor control systems. We describe cognitive-motor integration and how it relates to successfully navigating skilled activities crucial for work, duty, sport, and even daily life. We review our research on the behavioral effects of traumatic impact and blast exposure on cognitive-motor integration in both younger and older adults, and the neural networks that are involved in these types of skills. Overall, we have observed impairments in rule-based skilled performance as a function of both physical impact and blast exposure. The extent of these impairments depended on the age at injury and the sex of the individual. It appears, however, that cognitive-motor integration deficits can be mitigated by the level of skill expertise of the affected individual, suggesting that such experience imparts resiliency in the brain networks that underly the control of complex visuomotor performance. Finally, we discuss the next steps needed to comprehensively understand the impact of trauma and blast exposure on functional movement control.
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Affiliation(s)
- Lauren E. Sergio
- School of Kinesiology and Health Science, York University, Toronto, ON, Canada
- Centre for Vision Research, York University, Toronto, ON, Canada
| | - Diana J. Gorbet
- School of Kinesiology and Health Science, York University, Toronto, ON, Canada
- Centre for Vision Research, York University, Toronto, ON, Canada
| | - Meaghan S. Adams
- School of Kinesiology and Health Science, York University, Toronto, ON, Canada
- Vision-Science to Application (VISTA) Program, York University, Toronto, ON, Canada
- Toronto Rehabilitation Institute, University Health Network, Toronto, ON, Canada
| | - Danielle M. Dobney
- School of Kinesiology and Health Science, York University, Toronto, ON, Canada
- Vision-Science to Application (VISTA) Program, York University, Toronto, ON, Canada
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