Publications using the OxyMon
Investigating online effects of transcranial direct current stimulation from NIRS-EEG joint-imaging using Kalman Filter based online parameter estimation of an autoregressive model Investigating online effects of transcranial direct current stimulation fr
Although, there has been a significant improvement in neuroimaging technologies and analysis methods, the fundamental relationship between local changes in cerebral hemodynamics and the underlying neural activity remains largely unknown. The focus of …
Muscle VO2 and forearm blood flow repeatability during venous and arterial occlusions in healthy and coronary heart disease subjects
This study aims were: 1) to assess forearm blood flow (FBF) and muscle oxygen consumption (mVO2) repeatability assessed with near-infra red spectroscopy (NIRS) during venous occlusions (VO) in middle aged healthy subjects and patients with stable …
Subcutaneous and intramuscular hemodynamics and oxygenation after cold-spray application as monitored by near-infrared spectroscopy
Context: Vapocoolant spray, commonly known as cold spray (CS), is a cryotherapy modality used in sports medicine, athletic training, and rehabilitation settings. Proposed physiologic effects of cryotherapy modalities include reductions in tissue …
The Influence of Music on Prefrontal Cortex during Episodic Encoding and Retrieval of Verbal Information: A Multichannel fNIRS Study
Music can be thought of as a complex stimulus able to enrich the encoding of an event thus boosting its subsequent retrieval. However, several findings suggest that music can also interfere with memory performance. A better understanding of the …
Measurement of regional forearm muscle haemodynamics via the near-infrared spectroscopy venous occlusion technique: The impact of hand circulatory occlusion
The purpose of this study was to examine whether circulatory occlusion of the hand impacts on regional forearm muscle haemodynamics as determined by the near-infrared spectroscopy (NIRS) venous occlusion technique (NIRSVOT). Twenty-five young, …
Systemic oxidative-nitrosative-inflammatory stress during acute exercise in hypoxia; implications for microvascular oxygenation and aerobic capacity
New Findings: What is the central question of this study? Exercise performance is limited during hypoxia by a critical reduction in cerebral and skeletal tissue oxygenation. To what extent an elevation in systemic free radical accumulation …
Cortical implication in lower voluntary muscle force production in non-hypoxemic COPD patients
Recent studies have shown that muscle alterations cannot totally explain peripheral muscle weakness in COPD. Cerebral abnormalities in COPD are well documented but have never been implicated in muscle torque production. The purpose of this study was …
Electromyographic, cerebral, and muscle hemodynamic responses during intermittent, isometric contractions of the biceps brachii at three submaximal intensities
This study examined the electromyographic, cerebral and muscle hemodynamic responses during intermittent isometric contractions of biceps brachii at 20, 40, and 60% of maximal voluntary contraction (MVC). Eleven volunteers completed 2 min of …
Cerebral oxygenation during the Richalet hypoxia sensitivity test and cycling time-trial performance in severe hypoxia
Background: The Richalet hypoxia sensitivity test (RT), which quantifies the cardiorespiratory response to acute hypoxia during exercise at an intensity corresponding to a heart rate of $∼$130 bpm in normoxia, can predict susceptibility of altitude …
Less effort, better results: How does music act on prefrontal cortex in older adults during verbal encoding? an fNIRS study
Several neuroimaging studies of cognitive aging revealed deficits in episodic memory abilities as a result of prefrontal cortex (PFC) limitations. Improving episodic memory performance despite PFC deficits is thus a critical issue in aging research. …
Prefrontal cortex haemodynamics and affective responses during exercise: A multi-channel near infrared spectroscopy study
The dose-response effects of the intensity of exercise upon the potential regulation (through top-down processes) of affective (pleasure-displeasure) responses in the prefrontal cortex during an incremental exercise protocol have not been explored. …
AltitudeOmics: Exercise-induced supraspinal fatigue is attenuated in healthy humans after acclimatization to high altitude
Aims: We asked whether acclimatization to chronic hypoxia (CH) attenuates the level of supraspinal fatigue that is observed after locomotor exercise in acute hypoxia (AH). Methods: Seven recreationally active participants performed identical bouts of …
Breakpoints in ventilation, cerebral and muscle oxygenation, and muscle activity during an incremental cycling exercise
The aim of this study was to locate the breakpoints of cerebral and muscle oxygenation and muscle electrical activity during a ramp exercise in reference to the first and second ventilatory thresholds. Twenty-five cyclists completed a maximal ramp …
Assessment of dynamic cerebral autoregulation and cerebrovascular CO2 reactivity in ageing by measurements of cerebral blood flow and cortical oxygenation
New Findings: What is the central question in this study? It is unknown to what extent increasing age influences the dynamic adaptations of cerebral blood flow velocity and cortical oxygenation in response to changes in blood pressure (cerebral …
Influence of dietary nitrate supplementation on physiological and cognitive responses to incremental cycle exercise
Dietary inorganic nitrate supplementation causes physiological effects which may enhance exercise tolerance. However it is not known whether nitrate might alter cognitive function during exercise. In a double-blind, cross-over study, sixteen subjects …
Optical diagnosis of testicular torsion: feasibility and methodology
Background: Torsion of the testis compromises blood flow through the spermatic cord; testicular ischemia results which if not diagnosed promptly and corrected surgically irrevocably damages the testis. Current diagnostic modalities aimed at …
Repeated pre-syncope from increased inspired co2 in a background of severe hypoxia
We describe a case of experimentally induced pre-syncope in a healthy young man when exposed to increased inspired CO2 in a background of hypoxia. Acute severe hypoxia (FIO2=0.10) was tolerated, but adding CO2 to the inspirate caused pre-syncope …
Towards a near infrared spectroscopy-based estimation of operator attentional state
Given the critical risks to public health and safety that can involve lapses in attention (e.g., through implication in workplace accidents), researchers have sought to develop cognitive-state tracking technologies, capable of alerting individuals …
Acute exercise stress reveals cerebrovascular benefits associated with moderate gains in cardiorespiratory fitness
Elevated cardiorespiratory fitness improves resting cerebral perfusion, although to what extent this is further amplified during acute exposure to exercise stress and the corresponding implications for cerebral oxygenation remain unknown. To examine …
Acute oxygenation changes on ischemic foot of a novel intermittent pneumatic compression device and of an existing sequential device in severe peripheral arterial disease
Background: Intermittent pneumatic compression (IPC) improves haemodynamics in peripheral arterial disease (PAD), but its effects on foot perfusion were scarcely studied. In severe PAD patients we measured the foot oxygenation changes evoked by a …