Table 1.
Characteristics of 37 papers included in review.
| Reference | Country and study design | Study mTBI population | Mechanism of mTBI | Number of mTBI participants | Mean time post-injury (Days) | Mean age of mTBI participants (Years) | Sex of mTBI participants (% male) | Control type | Analysis type | Risk of bias |
|---|---|---|---|---|---|---|---|---|---|---|
| Delayed and disorganised brain activation detected with magnetoencephalography after mild traumatic brain injury (da Costa et al., 2015) | Canada, case-control | ED department, non-consecutive | Not specified | 16 | 33 | 31 | 100 | 16 HC | Task-based source analysis | Highest |
| Low-frequency connectivity is associated with mild traumatic brain injury (Dunkley et al., 2015) | Canada, case-control | ED department, non-consecutive | 7 Sports, 13 Civilian | 20 | 32 | 31 | 100 | 21 HC | RS source analysis, RS connectivity analysis | Intermediate |
| Default mode network oscillatory coupling is increased following concussion (Dunkley et al., 2018) | Canada, case-control | ED department, non-consecutive | Not specified | 26 | 32 | 31 | 100 | 24 HC | RS connectivity analysis | Lowest |
| Post-Traumatic stress constrains the dynamic repertoire of neural activity (Mišić et al., 2016) | Canada, case-control | ED department, non-consecutive | Not specified | 20 | 32 | 31 | 100 | 20 control soldiers, 20 civilian HC, 23 soldiers with PTSD | RS source analysis, RS connectivity analysis. | Intermediate |
| Reduced brain connectivity and mental flexibility in mild traumatic brain injury (Pang et al., 2016) | Canada, case-control | ED department, non-consecutive | Not specified | 16 | 33 | 31 | 100 | 16 HC | Task-based connectivity analysis (sensor space) | |
| Detecting Mild Traumatic Brain Injury Using Resting State Magnetoencephalographic Connectivity (Vakorin et al., 2016) | Canada, case-control | ED department, non-consecutive | Not specified | 20 | 32 | 31 | 100 | 21 HC | RS connectivity analysis, machine learning algorithm. | Lowest |
| Concussion Alters the Functional Brain Processes of Visual Attention and Working Memory (Shah-Basak et al., 2018) | Canada, case-control | ED department, non-consecutive | 4 Sports, 14 Civilian | 18 | 36 | 30 | 100 | 19 HC | Task-based source analysis | Intermediate |
| Activation of dominant hemisphere association cortex during naming as a function of cognitive performance in mild traumatic brain injury: Insights into mechanisms of lexical access (Popescu et al., 2017) | USA, cohort | PCS outpatient programme | Not specified | 57 | 1920 | 39 | 99 | None | Task-based source analysis | Highest |
| Reduced prefrontal MEG alpha-band power in mild traumatic brain injury with associated posttraumatic stress disorder symptoms (Popescu et al., 2016) | USA, cohort | PCS outpatient programme | Not specified | 32 | 1590 | 40 | 100 | None | RS source analysis | Highest |
| Post-traumatic stress disorder is associated with altered modulation of prefrontal alpha band oscillations during working memory (Popescu et al., 2019) | USA, cohort | PCS outpatient programme | Not specified | 35 | Not specified | 42 | 100 | None | Task-based source analysis | Highest |
| Altered cross-frequency coupling in resting-state MEG after mild traumatic brain injury (Antonakakis et al., 2016) | USA, case-control | Texas trauma centres | 2 Sports, 28 Civilian | 30 | Not specified | 29 | 60 | 50 HC | Connectivity analysis (sensor space), machine learning algorithm | Highest |
| Altered rich-club and frequency-dependent subnetwork organization in mild traumatic brain injury: A MEG resting-state study (Antonakakis et al., 2017) | USA, case-control | Texas trauma centres | 2 Sports, 28 Civilian | 30 | Not specified | 29 | 60 | 50 HC | Connectivity analysis (sensor space), network metrics, machine learning algorithm | Highest |
| Reconfiguration of dominant coupling modes in mild traumatic brain injury mediated by delta-band activity: A resting state MEG study (Antonakakis et al., 2017) | USA, case-control | Texas trauma centres | 2 Sports, 28 Civilian | 30 | Not specified | 29 | 60 | 50 HC | Connectivity analysis (sensor space), network metrics, machine learning algorithm | Highest |
| Data-Driven Topological Filtering Based on Orthogonal Minimal Spanning Trees: Application to Multigroup Magnetoencephalography Resting-State Connectivity (Dimitriadis et al., 2017) | USA, case-control | Texas trauma centres | 2 Sports, 28 Civilian | 30 | Not specified | 29 | 60 | 50 HC | Network metrics, machine learning algorithms | Highest |
| Functional connectivity changes detected with magnetoencephalography after mild traumatic brain injury (Dimitriadis et al., 2015) | USA, case-control | Texas trauma centres | 2 Sports, 29 Civilian | 31 | Not specified | 29 | 58 | 50 HC | Connectivity analysis (sensor space), network metrics, machine learning algorithm | Highest |
| Improving the Detection of mTBI Via Complexity Analysis in Resting - State Magnetoencephalography (Antonakakis et al., 2016) | USA, case-control | Texas trauma centres | 2 Sports, 28 Civilian | 30 | Not specified | 29 | 60 | 50 HC | Network metrics, machine learning algorithm | Highest |
| Functional connectivity changes in mild traumatic brain injury assessed using magnetoencephalography (Zouridakis et al., 2012) | USA, case-control | Texas trauma centres | Not specified | 10 | Not specified | 31 | 70 | 50 HC | Connectivity analysis (sensor space), machine learning algorithm | Highest |
| Magnetoencephalography slow-wave detection in patients with mild traumatic brain injury and ongoing symptoms correlated with long-term neuropsychological outcome (Robb Swan et al., 2015) | USA, case-control | TBI clinics with persistent PCS > 3 months | 6 Sports, 20 Blast related, 5 Civilian | 31 | 97 | 27 | 90 | 33 HC | RS source analysis | Intermediate |
| An automatic MEG low-frequency source imaging approach for detecting injuries in mild and moderate TBI patients with blast and non-blast causes (Huang et al., 2012) | USA, case-control | Veterans brain injury centre with persistent PCS | 23 Military, 22 Civilian | 45 | 250 | 28 | 84 | 44 HC | RS source analysis | Intermediate |
| Theta-Band Oscillations as an Indicator of Mild Traumatic Brain Injury (Kaltiainen et al., 2018) | Finland, case-control | Not specified | Not specified | 26 | Longitudinal | 41 | 58 | 139 HC from previous study dataset | RS source analysis | Highest |
| Mild traumatic brain injury affects cognitive processing and modifies oscillatory brain activity during attentional tasks (Kaltiainen et al., 2019) | Finland, case-control | Not specified | 4 Sports, 21 Civilian | 25 | Longitudinal | 42 | 56 | 20 HC | Task-based sensor space and source analyses | Intermediate |
| Source Connectivity Analysis Can Assess Recovery of Acute Mild Traumatic Brain Injury Patients (Li et al., 2018) | USA, case-control | Not specified | Not specified | 13 | Longitudinal | 26 | 54 | 8 orthopaedic trauma controls | RS connectivity analysis | Highest |
| Brain Activation Profiles in mTBI: Evidence from Combined Resting-State EEG and MEG Activity (Li et al., 2015) | USA, case-control | Not specified | Not specified | 6 | Not specified | 28 | 66 | 5 orthopaedic trauma controls | RS analysis (sensor space) | Highest |
| Contrasting Effects of Posttraumatic Stress Disorder and Mild Traumatic Brain Injury on the Whole-Brain Resting-State Network: A Magnetoencephalography Study (Rowland et al., 2017) | USA, case-control | Veterans | Military | 12 | 2265 | 39 | 100 | 10 HC | Network metrics | Highest |
| Increased Small-World Network Topology Following Deployment-Acquired Traumatic Brain Injury Associated with the Development of Post-Traumatic Stress Disorder (Rowland et al., 2018) | USA, cohort | Veterans | Military | 16 | 4138 | 40 | 100 | None | Network metrics | Highest |
| MEG Working Memory N-Back Task Reveals Functional Deficits in Combat-Related Mild Traumatic Brain Injury (Huang et al., 2019) | USA, case-control | Veterans or active-duty military personnel with persistent PCS | Military | 25 | 315 | 27 | 100 | 20 veterans or active-duty military personnel | Task-based source analysis | Lowest |
| Marked Increases in Resting-State MEG Gamma-Band Activity in Combat-Related Mild Traumatic Brain Injury (Huang et al., 2019) | USA, case-control | Veterans or active-duty military personnel with persistent PCS | Military | 25 | 594 | 28 | 100 | 35 veterans or active-duty military personnel | RS source analysis | Highest |
| Single-subject-based whole-brain MEG slow-wave imaging approach for detecting abnormality in patients with mild traumatic brain injury (Huang et al., 2014) | USA, case-control | Persistent PCS | 36 Military, 48 Civilian | 84 | 265 | 29 | 83 | 11 veterans or active-duty military personnel 68 civilian HC | RS source analysis | Highest |
| Resting-State Magnetoencephalography Reveals Different Patterns of Aberrant Functional Connectivity in Combat-Related Mild Traumatic Brain Injury (Huang et al., 2017) | USA, case-control | Veterans or active-duty military personnel | 26 Military | 26 | 508 | 28 | 100 | 22 veterans or active-duty military personnel | RS connectivity analysis | Highest |
| Integrated imaging approach with MEG and DTI to detect mild traumatic brain injury in military and civilian patients (Huang et al., 2009) | USA, case-control | Persistent PCS | 4 Sports, 4 Military, 2 Civilian | 10 | 353 | 25 | 90 | 14 HC | RS source analysis. | Highest |
| Attentional dysfunction and recovery in concussion: effects on the P300m and contingent magnetic variation (Petley et al., 2018) | Canada, case-control | Consecutive ED mTBI patients | 2 Sports, 11 Civilian | 13 | Longitudinal | 26 | 31 | 13 HC | Task-based ERFs | Highest |
| Complexity analysis of resting state magnetoencephalography activity in traumatic brain injury patients (Luo et al., 2013) | USA, case-control | Not specified | 15 Military, 3 Civilian | 18 | 1859 | 29 | 100 | 18 HC | Network metrics | Highest |
| Filling in the gaps: Anticipatory control of eye movements in chronic mild traumatic brain injury (Diwakar et al., 2015) | USA, case-control | mTBI clinic or neurology referrals with persistent PCS | 13 Sports, 12 Civilian | 25 | 968 | 33 | 84 | 25 HC including from other studies | Task-based source analysis | Highest |
| Objective documentation of traumatic brain injury subsequent to mild head trauma: Multimodal brain imaging with MEG, SPECT, and MRI (Lewine et al., 2007) | USA, cohort | Outpatient clinics with persistent PCS > 1 year | 30 Civilian | 30 | 1011 | 38 | 53 | None | RS source analysis | Highest |
| Neuromagnetic assessment of pathophysiologic brain activity induced by minor head trauma (Lewine et al., 1999) | USA, case-control, longitudinal | mTBI with or without PCS | Not specified | 30 | 345 | 36 | 60 | 20 HC | RS source analysis | Highest |
| Aberrant Whole-Brain Transitions and Dynamics of Spontaneous Network Microstates in Mild Traumatic Brain Injury (Antonakakis et al., 2020) | USA, case-control | Texas trauma centres | 2 Sports, 28 various | 30 | Not specified | 29 | 60 | 50 HC | Network metrics | Highest |
| Local and large-scale beta oscillatory dysfunction in males with mild traumatic brain injury (Zhang et al., 2020) | Canada, case-control | Non-consecutive ED mTBI patients | 12 Sports, 15 Civilian | 27 | 39 | 30 | 100 | 23 HC | RS source analysis, RS connectivity analysis | Intermediate |