Jonathan D. Smirl
YOU?
Author Swipe
View article: Exercise intolerance and time to medical clearance to return to sport following sport-related concussion in adolescents
Exercise intolerance and time to medical clearance to return to sport following sport-related concussion in adolescents Open
Objective Recovery duration following adolescent sport-related concussion (SRC) is variable. Previous research revealed exercise intolerance is associated with delayed recovery (predominantly male Australian cohort). Additional sport conte…
View article: Advocates, Academics, Survivors and Clinicians to END Intimate Partner Violence (ASCEND-IPV) initiative: a prospective observational case–control study protocol to identify plasma biomarkers of intimate partner violence (IPV)-caused brain injury (BI)
Advocates, Academics, Survivors and Clinicians to END Intimate Partner Violence (ASCEND-IPV) initiative: a prospective observational case–control study protocol to identify plasma biomarkers of intimate partner violence (IPV)-caused brain injury (BI) Open
Introduction Although as many as 92% of survivors of physical intimate partner violence (IPV) report impacts to the head and/or non-fatal strangulation (NFS) that raise clinical suspicion of brain injury (BI), there are no evidence-based m…
View article: Neurophysiology of Downhill Mountain Bike Athletes—Benchmark Assessments of Event-Related Potentials
Neurophysiology of Downhill Mountain Bike Athletes—Benchmark Assessments of Event-Related Potentials Open
Background: Downhill mountain biking (MTB) is a high-velocity sport where riders are potentially exposed to impacts and concussion. Rapidly obtained Event-Related Potentials (ERPs) are a promising use of portable electroencephalography for…
View article: Quantification of the cerebral pressure–flow relationship directional sensitivity: Reliability of shorter repeated squat–stand durations
Quantification of the cerebral pressure–flow relationship directional sensitivity: Reliability of shorter repeated squat–stand durations Open
The magnitude of changes in middle cerebral artery mean blood velocity (MCAv) is attenuated when mean arterial pressure (MAP) increases compared with when MAP decreases. This directional sensitivity has been characterized using a time‐corr…
View article: Effects of interval exercise and diurnal variation on blood biomarkers for sport-related concussion: A crossover cohort study
Effects of interval exercise and diurnal variation on blood biomarkers for sport-related concussion: A crossover cohort study Open
These preliminary findings highlight potential considerations for future sport-related concussion biomarker investigations collecting acute post-injury data in a sports context, as exercise may have immediate transient effects, and diurnal…
View article: Altered autonomic cardiovascular function in adults with persisting post‐concussive symptoms and exercise intolerance
Altered autonomic cardiovascular function in adults with persisting post‐concussive symptoms and exercise intolerance Open
Alterations in autonomic cardiovascular function may result following mild traumatic brain injury (mTBI), but there is a lack of data evaluating autonomic function in adults with persisting post‐concussive symptoms (PPCS). We collected res…
View article: Directional sensitivity analysis of the cerebral pressure-flow relationship during normothermia and moderate hyperthermia
Directional sensitivity analysis of the cerebral pressure-flow relationship during normothermia and moderate hyperthermia Open
Recent evidence highlights the importance of considering directional sensitivity in dynamic cerebral autoregulation. The current analysis found no directional sensitivity in the cerebral pressure-flow relationship during 0.03- and 0.10-Hz …
View article: Hypocapnia, eucapnia and hypercapnia during “Where’s Waldo” search paradigms: Neurovascular coupling across the cardiac cycle and biological sexes
Hypocapnia, eucapnia and hypercapnia during “Where’s Waldo” search paradigms: Neurovascular coupling across the cardiac cycle and biological sexes Open
This investigation explored the impact of partial pressure of end-tidal carbon dioxide (P ET CO 2 ) alterations on temporal neurovascular coupling (NVC) responses across the cardiac cycle and the influence of biological sex via a complex v…
View article: A multimodal neuroimaging study of cerebrovascular regulation: protocols and insights of combining electroencephalography, functional near-infrared spectroscopy, transcranial Doppler ultrasound, and physiological parameters
A multimodal neuroimaging study of cerebrovascular regulation: protocols and insights of combining electroencephalography, functional near-infrared spectroscopy, transcranial Doppler ultrasound, and physiological parameters Open
Objective . The current paper describes the creation of a simultaneous trimodal neuroimaging protocol. The authors detail their methodological design for a subsequent large-scale study, demonstrate the ability to obtain the expected physio…
View article: Quiet Stance Postural Control in Women Who Have a History of Brain Injury from Intimate Partner Violence: A Preliminary Study
Quiet Stance Postural Control in Women Who Have a History of Brain Injury from Intimate Partner Violence: A Preliminary Study Open
Intimate partner violence (IPV) frequently results in brain injury (IPV-BI) among survivors, with potential long-term effects for both physical and psychological health. This study aimed to examine the impact of chronic IPV-BI on postural …
View article: Evaluating a 12-week aerobic exercise intervention in adults with persisting post-concussive symptoms
Evaluating a 12-week aerobic exercise intervention in adults with persisting post-concussive symptoms Open
Background Although guidelines support aerobic exercise in sub-acute mild traumatic brain injury (mTBI), evidence for adults with persisting post-concussive symptoms (PPCS) after mTBI is lacking. The objective was to evaluate the impact of…
View article: Consequences of adolescent sport-related concussion: exploring long-term cardiorespiratory fitness and adiposity
Consequences of adolescent sport-related concussion: exploring long-term cardiorespiratory fitness and adiposity Open
It is possible to maintain adequate long-term cardiorespiratory fitness and adiposity following adolescent SRC relative to those who only sustained sport related MSK injuries or did not sustain significant injuries as adolescents/adults.
View article: Challenging dynamic cerebral autoregulation across the physiological CO<sub>2</sub> spectrum: Influence of biological sex and cardiac cycle
Challenging dynamic cerebral autoregulation across the physiological CO<sub>2</sub> spectrum: Influence of biological sex and cardiac cycle Open
This study applied alterations in partial pressure of end‐tidal carbon dioxide () to challenge dynamic cerebral autoregulation (dCA) responses across the cardiac cycle in both biological sexes. A total of 20 participants (10 females and 10…
View article: Quantifying neurovascular coupling through a concurrent assessment of arterial, capillary, and neuronal activation in humans: A multimodal EEG-fNIRS-TCD investigation
Quantifying neurovascular coupling through a concurrent assessment of arterial, capillary, and neuronal activation in humans: A multimodal EEG-fNIRS-TCD investigation Open
This investigation demonstrated the feasibility of the proposed EEG-fNIRS-TCD response to comprehensively assess the NVC response within human, specifically quantifying the real-time temporal synchrony between neuronal activation (EEG), mi…
View article: Physiological influences on neurovascular coupling: A systematic review of multimodal imaging approaches and recommendations for future study designs
Physiological influences on neurovascular coupling: A systematic review of multimodal imaging approaches and recommendations for future study designs Open
In this review, we have amalgamated the literature, taking a multimodal neuroimaging approach to quantify the relationship between neuronal firing and haemodynamics during a task paradigm (i.e., neurovascular coupling response), while cons…
View article: Examining the upper frequency limit of dynamic cerebral autoregulation: Considerations across the cardiac cycle during eucapnia
Examining the upper frequency limit of dynamic cerebral autoregulation: Considerations across the cardiac cycle during eucapnia Open
There are differences within the literature regarding the upper frequency cut‐off point of the dynamic cerebral autoregulation (CA) high‐pass filter. The projection pursuit regression approach has demonstrated that the upper frequency limi…
View article: Plasma Biomarkers of Traumatic Brain Injury in Adolescents With Sport-Related Concussion
Plasma Biomarkers of Traumatic Brain Injury in Adolescents With Sport-Related Concussion Open
Importance Blood-based biomarkers may clarify underlying neuropathology and potentially assist in clinical management of adolescents with sport-related concussion (SRC). Objective To investigate the association between SRC and plasma bioma…
View article: Neurovascular coupling methods in healthy individuals using transcranial doppler ultrasonography: A systematic review and consensus agreement
Neurovascular coupling methods in healthy individuals using transcranial doppler ultrasonography: A systematic review and consensus agreement Open
Neurovascular coupling (NVC) is the perturbation of cerebral blood flow (CBF) to meet varying metabolic demands induced by various levels of neural activity. NVC may be assessed by Transcranial Doppler ultrasonography (TCD), using task act…
View article: Feasibility of superimposed supine cycling and lower body negative pressure as an effective means of prolonging exercise tolerance in individuals experiencing persisting post‐concussive symptoms: Preliminary results
Feasibility of superimposed supine cycling and lower body negative pressure as an effective means of prolonging exercise tolerance in individuals experiencing persisting post‐concussive symptoms: Preliminary results Open
To examine the feasibility, utility and safety of superimposed lower body negative pressure (LBNP) and tilt during supine cycling in individuals suffering from persisting post‐concussive symptoms (PPCS). Eleven individuals aged 17–31 (6 fe…
View article: Sensor-Assisted Analysis of Autonomic and Cerebrovascular Dysregulation following Concussion in an Individual with a History of Ten Concussions: A Case Study
Sensor-Assisted Analysis of Autonomic and Cerebrovascular Dysregulation following Concussion in an Individual with a History of Ten Concussions: A Case Study Open
Introduction: Concussion is known to cause transient autonomic and cerebrovascular dysregulation that generally recovers; however, few studies have focused on individuals with an extensive concussion history. Method: The case was a 26-year…
View article: On the challenge of assessing dynamic cerebral autoregulation
On the challenge of assessing dynamic cerebral autoregulation Open
Connections link a sequence of three related research papers. The central article which links the other two papers has been published in Experimental Physiology. In a Connections article, an author (or authors) of the central article outli…
View article: Time-domain methods for quantifying dynamic cerebral blood flow autoregulation: Review and recommendations. A white paper from the Cerebrovascular Research Network (CARNet)
Time-domain methods for quantifying dynamic cerebral blood flow autoregulation: Review and recommendations. A white paper from the Cerebrovascular Research Network (CARNet) Open
Cerebral Autoregulation (CA) is an important physiological mechanism stabilizing cerebral blood flow (CBF) in response to changes in cerebral perfusion pressure (CPP). By maintaining an adequate, relatively constant supply of blood flow, C…
View article: A Four-Country Study of Strangulation-Related Alterations in Consciousness in Women Who Have Experienced Intimate Partner Violence: Co-Occurrence with Traumatic Brain Injuries and Measures of Psychological Distress
A Four-Country Study of Strangulation-Related Alterations in Consciousness in Women Who Have Experienced Intimate Partner Violence: Co-Occurrence with Traumatic Brain Injuries and Measures of Psychological Distress Open
At least one in three women experience intimate partner violence (IPV) in their lifetime. The most commonly sustained IPV-related brain injuries include strangulation-related alterations in consciousness (S-AICs) and traumatic brain injuri…
View article: Maximizing the Reliability and Precision of Measures of Prefrontal Cortical Oxygenation Using Frequency-Domain Near-Infrared Spectroscopy
Maximizing the Reliability and Precision of Measures of Prefrontal Cortical Oxygenation Using Frequency-Domain Near-Infrared Spectroscopy Open
Frequency-domain near-infrared spectroscopy (FD-NIRS) has been used for non-invasive assessment of cortical oxygenation since the late 1990s. However, there is limited research demonstrating clinical validity and general reproducibility. T…
View article: A systematic review, meta-analysis <i>and</i> meta-regression amalgamating the driven approaches used <i>to</i> quantify dynamic cerebral autoregulation
A systematic review, meta-analysis <i>and</i> meta-regression amalgamating the driven approaches used <i>to</i> quantify dynamic cerebral autoregulation Open
Numerous driven techniques have been utilized to assess dynamic cerebral autoregulation (dCA) in healthy and clinical populations. The current review aimed to amalgamate this literature and provide recommendations to create greater standar…
View article: Dynamic cerebral autoregulation quantification with spontaneous arterial blood pressure oscillations: Is transfer function analysis our best option?
Dynamic cerebral autoregulation quantification with spontaneous arterial blood pressure oscillations: Is transfer function analysis our best option? Open
Transfer function analysis (TFA) is a widely used analytical method to quantify dynamic cerebral autoregulation (dCA), which represents the ability of the cerebrovasculature to buffer transient changes in arterial blood pressure (ABP). Thi…