Publications using the PortaLite
Home-based monitoring of cerebral oxygenation in response to postural changes using near-infrared spectroscopy
Orthostatic hypotension (OH) is prevalent in older adults and can cause falls and hospitalization. Diagnostic intermittent blood pressure (BP) measurements are only a proxy for cerebral perfusion and do not reflect daily-life BP fluctuations. …
Prefrontal cortex oxygenation during a mentally fatiguing task in normoxia and hypoxia
Mental fatigue (MF) and hypoxia impair cognitive performance through changes in brain hemodynamics. We want to elucidate the role of prefrontal cortex (PFC)-oxygenation in MF. Twelve participants (22.9 ± 3.5 years) completed four experimental trials, …
Impact of acute hypoxic exposure on neuromuscular and hemodynamic responses during step intensity dynamic constant external resistance leg extension exercise
Objectives This study examined the effects of acute normoxic and hypoxic exposure on neuromuscular and hemodynamic physiological responses performed during dynamic step muscle actions. Methods Thirteen recreationally active men (mean ± SD age: 21.2 …
A single exposure to 100% normo-baric oxygen therapy appears to improve sequence learning processes by increasing prefrontal cortex oxygen saturation
Previously, we showed that a normo-baric 100 % oxygen treatment (NbOxTr) enhances motor learning processes, e.g., visuomotor adaptation (VMA) and sequence learning (SL). However, this work was limited to behavioral outcomes and did not identify the …
Assessment of Microvascular Hemodynamic Adaptations in Finger Flexors of Climbers
Climbing performance is greatly dependent on the endurance of the finger flexors which, in turn, depends on the ability to deliver and use oxygen within the muscle. Near-infrared spectroscopy (NIRS) and diffuse correlation spectroscopy (DCS) have …
Defecation after magnesium supplementation enhances cognitive performance in triathletes
Constipation is correlated with diminished cognitive function, revealing a possible rectum-brain connection. In this counter-balanced crossover trial, 13 elite triathletes underwent a Stroop test to assess cognitive function and executive control. …
Near-Infrared Spectroscopy Does Not Track Forearm Blood Flow during Venous Occlusion Plethysmography
Background: Venous occlusion plethysmography (VOP) non-invasively measures forearm blood flow (FBF), whereas near-infrared spectroscopy (NIRS) assesses skeletal muscle oxygenation. Using these techniques has revealed sex differences in microvascular …
Near-Infrared Spectroscopy During Reactive Hyperemia for the Assessment of Lower Limb Vascular Function
Vascular diseases of the lower limb contribute substantially to the global burden of cardiovascular disease and comorbidities such as diabetes. Importantly, microvascular dysfunction can occur prior to, or alongside, macrovascular pathology, and both …
Insight into brain-muscle oxygenation relationship before and after anaerobic threshold using near-infrared spectroscopy: a feasibility study
Monitoring the oxygenation levels of the prefrontal cortex during exercise is crucial in assessing decision-making abilities and cognitive responsibilities. Near-infrared spectroscopy (NIRS) is a non-invasive optical technique that measures and …
Near Infrared Spectroscopy (NIRS) Observation of Vastus Lateralis (Muscle) and Prefrontal Cortex (Brain) Tissue Oxygenation During Synchronised Swimming Routines in Elite Athletes
The development of underwater Near-Infrared Spectroscopy (uNIRS) has enabled the measurement of tissue oxygenation within the swim environment. Unique physiological responses, such as the diving reflex, have been shown to occur during synchronized …
The effect of cardiorespiratory fitness and habitual physical activity on cardiovascular responses to 2-hours of uninterrupted sitting
Prolonged uninterrupted sitting of textgreater3-hours has been shown to acutely cause central and peripheral cardiovascular dysfunction. However, individuals rarely sit uninterrupted for textgreater2-hours, and the cardiovascular response to this …
Impaired hemodynamics of the patella in patients with patellofemoral pain: A case–control study
Purpose: According to the homeostasis model, patellofemoral pain (PFP) arises as a consequence of disturbed homeostasis of anterior structures of the knee due to vascular insufficiency. Near‐infrared spectroscopy (NIRS) allows to measure changes of …
Myoelectric, Myo-Oxygenation, and Myotonometry Changes during Robot-Assisted Bilateral Arm Exercises with Varying Resistances
Robot-assisted bilateral arm training has demonstrated its effectiveness in improving motor function in individuals post-stroke, showing significant enhancements with increased repetitions. However, prolonged training sessions may lead to both mental …
Myofascial release induces declines in heart rate and changes to microvascular reactivity in young healthy adults
Objectives The purpose of this study was to compare physiological responses to myofascial release (MFR) and passive limb movement (PLM). Design Nineteen (23 ± 2.6yrs) adults (10 men and 9 women) completed two experiments on separate days: MFR and …
Sex‐specific microvascular and hemodynamic responses to passive limb heating in young adults
Objective: We examined sex‐specific microvascular reactivity and hemodynamic responses under conditions of augmented resting blood flow induced by passive heating compared to normal blood flow. Methods:Thirty‐eight adults (19 females) completed a …
Sport-related concussion alters cerebral hemodynamic activity during controlled respiration
Sport-related concussion (SRC) is known to disrupt neuro-hemodynamic activity, cardiac function, and blood pressure (BP) autoregulation. This study aims to observe changes in cerebrovascular and cardiovascular responses during controlled respiration …
Standing middle cerebral artery velocity predicts cognitive function and gait speed in older adults with cognitive impairment, and is impacted by sex differences
Upright posture challenges the cerebrovascular system, leading to changes in middle cerebral artery velocity (MCAv) dynamics which are less evident at supine rest. Chronic alterations in MCAv have been linked to hypoperfusion states and the effect …
Were Frailty Identification Criteria Created Equal? A Comparative Case Study on Continuous Non-Invasively Collected Neurocardiovascular Signals during an Active Standing Test in the Irish Longitudinal Study on Ageing (TILDA)
Background: In this observational study, we compared continuous physiological signals during an active standing test in adults aged 50 years and over, characterised as frail by three different criteria, using data from The Irish Longitudinal Study on …
Long-term effects of multiple concussions on prefrontal cortex oxygenation during a hypercapnic challenge in retired contact sport athletes
This exploratory study aimed to investigate the long-term effects of multiple concussions on prefrontal cortex oxygenation during a five-minute hypercapnic challenge using Near Infrared Spectroscopy (NIRS). 55 physically active retired contact sport …
Prefrontal cortex hemodynamic activity during a test of lower extremity functional muscle strength in children with cerebral palsy: A functional near‐infrared spectroscopy study
Abstract Children with cerebral palsy (CP) exhibit impaired motor control and significant muscle weakness due to a brain lesion. However, studies that assess the relationship between brain activity and performance on dynamic functional muscle …