Different Time Evolution of Oxyhemoglobin and Deoxyhemoglobin Concentration Changes in the Visual and Motor Cortices during Functional Stimulation: A Near-Infrared Spectroscopy Study

Wolf, Martin; Wolf, Ursula; Toronov, Vladislav; Michalos, Antonios; Paunescu, Lelia Adelina; Choi, Jee Hyun; Gratton, Enrico

doi:10.1006/nimg.2002.1128

Cited by 175 publications

(147 citation statements)

References 27 publications

Supporting

Mentioning

133

Contrasting

Order By: Relevance

“…Our data are also consistent with simultaneous fMRI and fNIRS experiments showing a high correlation between the BOLD signal and deoxy-Hb (Kida et al, 1996;Mehagnoul-Schipper et al, 2002;Punwani et al, 1997Punwani et al, , 1998Toronov et al, 2003) and with Pouratian et al (2002) who showed a high temporal and spatial correlation between the BOLD signal and optical intrinsic signals measured at 610 nm (particularly sensitive to deoxy-Hb) in humans. Differences to Strangman et al (2002), who found a lower correlation of the BOLD signal with deoxy-compared with oxy-Hb during finger flexion/ extension motor activation, may be explained by their less (three) subjects, different (block) design, their shorter emitter -detector separation (Germon et al, 1999), and non-linear changes of oxyHb in relation to deoxy-Hb in the motor cortex (Wolf et al, 2002). Because of the known linear relationship between changes of oxyand deoxy-Hb in the visual cortex ( Fig.…”

Section: Discussionmentioning

confidence: 86%

See 1 more Smart Citation

Investigating the post-stimulus undershoot of the BOLD signal—a simultaneous fMRI and fNIRS study

et al. 2006

View full text Add to dashboard Cite

Measuring the hemodynamic response with functional magnetic resonance imaging (fMRI) together with functional near-infrared spectroscopy (fNIRS) may overcome limitations of single-method approaches. Accordingly, we measured the event-related hemodynamic response with both imaging methods simultaneously in young subjects during visual stimulation. An intertrial interval of 60 s was chosen to include the prolonged post-stimulus undershoot of the blood oxygenation level dependent (BOLD) signal. During visual stimulation, the BOLD signal, oxy-, and total hemoglobin (Hb) increased, whereas deoxy-Hb decreased. The post-stimulus period was characterized by an undershoot of the BOLD signal, oxy-Hb, and an overshoot of deoxy-Hb. Total Hb as measured by fNIRS returned to baseline immediately after the end of stimulation. Results suggest that the post-stimulus events as measured by fNIRS are dominated by a prolonged high-level oxygen consumption in the microvasculature. The contribution of a delayed return of blood volume to the BOLD post-stimulus undershoot in post-capillary veins as suggested by the Balloon and Windkessel models remains ambiguous. Temporal changes in the BOLD signal were highly correlated with deoxy-Hb, with lower correlation values for oxy-and total Hb. Furthermore, data show that fNIRS covers the outer 1 cm of the brain cortex. These results were confirmed by simultaneous fMRI/fNIRS measurements during rest. In conclusion, multimodal imaging approaches may contribute to the understanding of neurovascular coupling. D

show abstract

Section: Discussionmentioning

confidence: 86%

“…Because of the known linear relationship between changes of oxyand deoxy-Hb in the visual cortex ( Fig. 3; Wolf et al, 2002), we decided to apply a visual paradigm in contrast to their study.…”

Section: Discussionmentioning

confidence: 99%

Investigating the post-stimulus undershoot of the BOLD signal—a simultaneous fMRI and fNIRS study

et al. 2006

View full text Add to dashboard Cite

show abstract

“…Franceschini et al, 2003;Maki et al, 1995;Wolf et al, 2002). These approaches employed a simple backprojection algorithm, which offered a resolution in the order of the average distance between the midpoints of light bundles (Yamamoto et al, 2002).…”

Section: Probe Designmentioning

confidence: 99%

“…Functional brain activity (SC1) in fNIRI signals originates from evoked local neurovascular coupling (Buxton, 2012;Devor et al, 2012) and is directly related to functional brain activity (see Table 4). The signal changes associated with this component are small (i.e.~0.5 μM for [O 2 Hb],~−0.2 μM for [HHb] (Wolf et al, 2002)) in relation to the overall variability of the fNIRI signals (in general~1 μM for [O 2 Hb] as well as [HHb]). The component is generally termed "stimulus/(or task)-evoked hemodynamic response" and its extraction from the fNIRI signals is of primary interest in most fNIRI studies.…”

Section: Classification Of Signal Componentsmentioning

confidence: 99%

“…Brain activity leads to an increase in oxygen consumption, which is accompanied by an increase in cerebral blood flow due to neurovascular coupling. This leads to a change in the local [O 2 Hb] and [HHb] (Wolf et al, 2002), which can be detected non-invasively by fNIRS. These first measurements were carried out with simple instruments, which measured at one or a few locations.…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

A review on continuous wave functional near-infrared spectroscopy and imaging instrumentation and methodology

Scholkmann¹,

Kleiser²,

Metz³

et al. 2014

NeuroImage

Self Cite

1,418

1,394

View full text Add to dashboard Cite

This year marks the 20th anniversary of functional near-infrared spectroscopy and imaging (fNIRS/fNIRI). As the vast majority of commercial instruments developed until now are based on continuous wave technology, the aim of this publication is to review the current state of instrumentation and methodology of continuous wave fNIRI. For this purpose we provide an overview of the commercially available instruments and address instrumental aspects such as light sources, detectors and sensor arrangements. Methodological aspects, algorithms to calculate the concentrations of oxy-and deoxyhemoglobin and approaches for data analysis are also reviewed. From the single-location measurements of the early years, instrumentation has progressed to imaging initially in two dimensions (topography) and then three (tomography). The methods of analysis have also changed tremendously, from the simple modified Beer-Lambert law to sophisticated image reconstruction and data analysis methods used today. Due to these advances, fNIRI has become a modality that is widely used in neuroscience research and several manufacturers provide commercial instrumentation. It seems likely that fNIRI will become a clinical tool in the foreseeable future, which will enable diagnosis in single subjects. This year marks the 20th anniversary of functional near-infrared spectroscopy and imaging (fNIRS/fNIRI). As the vast majority of commercial instruments developed until now are based on continuous wave technology, the aim of this publication is to review the current state of instrumentation and methodology of continuous wave fNIRI. For this purpose we provide an overview of the commercially available instruments and address instrumental aspects such as light sources, detectors and sensor arrangements. Methodological aspects, algorithms to calculate the concentrations of oxy-and deoxyhemoglobin and approaches for data analysis are also reviewed. From the single-location measurements of the early years, instrumentation has progressed to imaging initially in two dimensions (topography) and then three (tomography). The methods of analysis have also changed tremendously, from the simple modified Beer-Lambert law to sophisticated image reconstruction and data analysis methods used today. Due to these advances, fNIRI has become a modality that is widely used in neuroscience research and several manufacturers provide commercial instrumentation. It seems likely that fNIRI will become a clinical tool in the foreseeable future, which will enable diagnosis in single subjects. Contents

show abstract

Assessment of intermittent UMTS electromagnetic field effects on blood circulation in the human auditory region using a near‐infrared system

Spichtig

Scholkmann

Chin

et al. 2011

Bioelectromagnetics

Self Cite

View full text Add to dashboard Cite

The aim of the present study was to assess the potential effects of intermittent Universal Mobile Telecommunications System electromagnetic fields (UMTS-EMF) on blood circulation in the human head (auditory region) using near-infrared spectroscopy (NIRS) on two different timescales: short-term (effects occurring within 80 s) and medium-term (effects occurring within 80 s to 30 min). For the first time, we measured potential immediate effects of UMTS-EMF in real-time without any interference during exposure. Three different exposures (sham, 0.18 W/kg, and 1.8 W/kg) were applied in a controlled, randomized, crossover, and double-blind paradigm on 16 healthy volunteers. In addition to oxy-, deoxy-, and total haemoglobin concentrations ([O(2) Hb], [HHb], and [tHb], respectively), the heart rate (HR), subjective well-being, tiredness, and counting speed were recorded. During exposure to 0.18 W/kg, we found a significant short-term increase in Δ[O(2) Hb] and Δ[tHb], which is small (17%) compared to a functional brain activation. A significant decrease in the medium-term response of Δ[HHb] at 0.18 and 1.8 W/kg exposures was detected, which is in the range of physiological fluctuations. The medium-term ΔHR was significantly higher (+1.84 bpm) at 1.8 W/kg than for sham exposure. The other parameters showed no significant effects. Our results suggest that intermittent exposure to UMTS-EMF has small short-and medium-term effects on cerebral blood circulation and HR. The aim of the present study was to assess the potential effects of intermittent Universal Mobile Telecommunications System electromagnetic fields (UMTS-EMF) on blood circulation in the human head (auditory region) using near-infrared spectroscopy (NIRS) on two different time-scales: short-term (effects occurring within 80 s) and medium-term (effects occurring within 80 s to 30 min

show abstract

Different Time Evolution of Oxyhemoglobin and Deoxyhemoglobin Concentration Changes in the Visual and Motor Cortices during Functional Stimulation: A Near-Infrared Spectroscopy Study

Cited by 175 publications

References 27 publications

Investigating the post-stimulus undershoot of the BOLD signal—a simultaneous fMRI and fNIRS study

Investigating the post-stimulus undershoot of the BOLD signal—a simultaneous fMRI and fNIRS study

A review on continuous wave functional near-infrared spectroscopy and imaging instrumentation and methodology

Assessment of intermittent UMTS electromagnetic field effects on blood circulation in the human auditory region using a near‐infrared system

Contact Info

Product

Resources

About