Publications using the PortaLite
Treadmill walking reduces pre-frontal activation in patients with Parkinson's disease
Background: Among patients with Parkinson's disease (PD), gait is typically disturbed and less automatic. These gait changes are associated with impaired rhythmicity and increased prefrontal activation, presumably in an attempt to compensate for …
Influence of exercise duration on cardiorespiratory responses, energy cost and tissue oxygenation within a 6 hour treadmill run
Purpose. The physiological mechanisms for alterations in oxygen utilization (V˙O2) and the energy cost of running (Cr) during prolonged running are not completely understood, and could be linked with alterations in muscle and cerebral tissue …
When is Higher Level Cognitive Control Needed for Locomotor Tasks Among Patients with Parkinson's Disease?
Turning has been implicated as a complex task that requires both motor and cognitive resources. Accumulating evidence shows that patients with Parkinson's disease (PD) require more steps and more time to complete a turn, however, the role of the …
Prediction of oxygen uptake dynamics by machine learning analysis of wearable sensors during activities of daily living
Currently, oxygen uptake (VO2) is the most precise means of investigating aerobic fitness and level of physical activity; however, VO2 can only be directly measured in supervised conditions. With the advancement of new wearable sensor technologies …
Oxygenation dynamics of sepsis patients undergoing far-infrared intervention based on near-infrared spectroscopy
Near-infrared spectroscopy (NIRS; continuous wave type) is a noninvasive tool for detecting the relative change of oxyhemoglobin and deoxyhemoglobin. To make this change, intervention methods must be applied. This study determined the hemodynamics of …
Effects of aging on prefrontal brain activation during challenging walking conditions
Background Deficits in cognitive domains, in particular, those related to the prefrontal cortex, contribute to diminished walking performance in complex conditions in older age. Studies using functional near infra-red spectroscopy (fNIRS) reported …
Possible Influence of Perturbation Implication, a Neurorehabilitation Model, On Brain Plasticity Using NIRS System
Improvements in the treatment of stroke lead to an increase in the number of patients living with the consequences of stroke. Although stroke induces cognitive impairment, a lack in mobility or difficulties in walking are common problems for stroke …
Sex differences in the oxygen delivery, extraction, and uptake during moderate-walking exercise transition
Previous studies in children and older adults demonstrated faster oxygen uptake (VO2) kinetics in males compared with females, but young healthy adults have not been studied. We hypothesized that young men would have faster aerobic system dynamics in …
Measuring prefrontal cortical activity during dual task walking in patients with Parkinson's disease: Feasibility of using a new portable fNIRS device
Background: Many patients with Parkinson's disease (PD) have difficulties in performing a second task during walking (i.e., dual task walking). Functional near-infrared spectroscopy (fNIRS) is a promising approach to study the presumed contribution …
Effect of hypoxia on cerebrovascular and cognitive function during moderate intensity exercise
Exercise in hypoxia places added demands on the brain and cerebrovasculature that can impact cognitive function. The purpose of this study was to investigate the effect of acute hypoxia on cerebrovascular hemodynamics, markers of neuro-steroidal …
Forearm muscle oxidative capacity index predicts sport rock-climbing performance
Abstract: Rock-climbing performance is largely dependent on the endurance of the forearm flexors. Recently, it was reported that forearm flexor endurance in elite climbers is independent of the ability to regulate conduit artery (brachial) blood …
The validity and reliability of continuous-wave near-infrared spectroscopy for the assessment of leg blood volume during an orthostatic challenge
Near-infrared spectroscopy (NIRS) can potentially be used to assess the cardiovascular autonomic system by monitoring orthostatic challenge-induced shifts in lower limb blood volume. However, in order to be of clinical utility the test must be valid, …
Investigating the impact of passive external lower limb compression on central and peripheral hemodynamics during exercise
Purpose: The objective of this study was to assess the effectiveness of graduated compression socks (GCS) on enhancing muscle blood flow and oxygenation during exercise and recovery in healthy subjects. Methods: Twelve healthy volunteers completed a …
Effect of acute hypoxia on inspiratory muscle oxygenation during incremental inspiratory loading in healthy adults
Purpose: To non-invasively examine the effect of acute hypoxia and inspiratory threshold loading (ITL) on inspiratory muscles [sternocleidomastoid (SCM), scalene (SA) and parasternal (PS)] oxygenation in healthy adults using near-infrared …
Effects of continuous and intermittent exercise on executive function in children aged 8-10 years
Understanding the effects of acute exercise on executive function in prepubescent children may be important for the enhancement of school performance. This study assessed the effect of an acute bout of continuous (CONT) or intermittent (INT), …
Frequency domain analysis of cerebral near infrared spectroscopy signals during application of an impedance threshold device in spontaneously ventilating volunteers
Currently available near infrared spectroscopy (NIRS) devices are unable to discriminate between arterial and venous blood, a potential source of artifact. The purpose of this study was to test the hypothesis that oscillations in NIR signals at the …
MAP, cerebral Oxygenation and tes-mep variabilty's in scolios surgery
Objective: At this moment, a wake-up test needs to be done when amplitudes of TES-MEP monitoring decrease irreversible during scoliosis surgery, what mostly turns out to be a false-positive. To make TES-MEP measurements more reliable, we need to know …
The effect of active versus passive recovery periods during high intensity intermittent exercise on local tissue oxygenation in 18-30 year old sedentary men
Purpose: High intensity interval training (HIIT) has been proposed as a time-efficient format of exercise to reduce the chronic disease burden associated with sedentary behaviour. Changes in oxygen utilisation at the local tissue level during an …
The effect of short and long term endurance training on systemic, and muscle and prefrontal cortex tissue oxygen utilisation in 40-60 year old women
Purpose: Aerobic endurance training (ET) increases systemic and peripheral oxygen utilisation over time, the adaptation pattern not being linear. However, the timing and mechanisms of changes in oxygen utilisation, associated with training beyond one …
The Role of the Frontal Lobe in Complex Walking among Patients with Parkinson's Disease and Healthy Older Adults: An fNIRS Study
Background. Gait is influenced by higher order cognitive and cortical control mechanisms. Functional near infrared spectroscopy (fNIRS) has been used to examine frontal activation during walking in healthy older adults, reporting increased oxygenated …