Disparity of activation onset in sensory cortex from simultaneous auditory and visual stimulation: Differences between perfusion and blood oxygenation level‐dependent functional magnetic resonance imaging

Liu, Ho-Ling Anthony; Feng, Ching Mei; Li, Jinqi; Su, Fan; Li, Ning; Glahn, David C.; Gao, Jia

doi:10.1002/jmri.20242

Cited by 5 publications

(4 citation statements)

References 30 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Among the three timing indices, TTH showed the smallest variance (Table 1). Therefore, analogous to several previous studies (Descamps et al, 2012; Liu et al, 2005; Waugh et al, 2008; Weilke et al, 2001) and consistent with our prediction that TTH may offer more robust estimates than Onset and TTP , TTH was considered the most reliable measure of HDR latency (results for Onset and TTP are, however, reported as well; see Tables 1 and 2). …”

Section: Resultssupporting

confidence: 92%

fMRI hemodynamics accurately reflects neuronal timing in the human brain measured by MEG

et al. 2013

View full text Add to dashboard Cite

Neuronal activation sequence information is essential for understanding brain functions. Extracting such timing information from blood oxygenation level dependent (BOLD) fMRI is confounded by interregional neurovascular differences and poorly understood relations between BOLD and electrophysiological response delays. Here, we recorded whole-head BOLD fMRI at 100 ms resolution and magnetoencephalography (MEG) during a visuomotor reaction-time task. Both methods detected the same activation sequence across five regions, from visual towards motor cortices, with linearly correlated interregional BOLD and MEG response delays. The smallest significant interregional BOLD delay was 100 ms; all delays ≥400 ms were significant. Switching the order of external events reversed the sequence of BOLD activations, indicating that interregional neurovascular differences did not confound the results. This may open new avenues for using fMRI to follow rapid activation sequences in the brain.

show abstract

Section: Resultssupporting

confidence: 92%

fMRI hemodynamics accurately reflects neuronal timing in the human brain measured by MEG

et al. 2013

View full text Add to dashboard Cite

show abstract

“…In humans, there is evidence for a faster increase in CBF than in BOLD in response to focal brain activation (10). However, most of the data assessing the early aspects of the temporal response of hemodynamic signals have been obtained in rat somatosensory cortex.…”

mentioning

confidence: 99%

Functional MRI impulse response for BOLD and CBV contrast in rat somatosensory cortex

Silva

Koretsky

Duyn

2007

Magnetic Resonance in Med

125

118

View full text Add to dashboard Cite

The contrast mechanism in functional MRI (fMRI) results from several vascular processes with different time scales, thus establishing a finite temporal resolution to fMRI experiments. In this work we measured the blood oxygen level-dependent (BOLD) and iron-oxide-derived cerebral blood volume (CBV) impulse response (IR) in a rat model of somatosensory brain activation at 11.7T. A binary m-sequence probe method was used to obtain high-sensitivity single-pixel estimates of the IR, from which two parameters-the full width at half maximum (FWHM) and the time to peak (TTP)-were determined as indices of the temporal resolution of the hemodynamic response ( The coupling between electrical activity and cerebral hemodynamics forms the basis of modern functional neuroimaging techniques (1). Through the cerebrovascular coupling, local increases in electrical activity are accompanied by measurable local changes in cerebral blood flow (CBF), blood volume (CBV), and blood oxygenation. These physiological quantities act as surrogate markers of increased brain activity during functional neuroimaging.This ensuing functional hemodynamic response (HDR) can be thought of as consisting of several concomitant and consecutive processes with different time scales. Through the cerebrovascular coupling, local decreases in vascular resistance lead to an increase in local blood volume and flow. This is mediated by smooth muscle cells and pericytes on the walls of arterioles and capillaries, which relax their tone in response to local increases in synaptic activity (2,3). The increase in blood flow results in a local inflow of oxyhemoglobin and a decrease in deoxyhemoglobin in the capillaries and veins. The latter causes an MRI signal and forms the basis of blood oxygen leveldependent (BOLD) contrast (4). Upon cessation of the increased electrical activity, the neurovascular coupling process causes restoration of the capillary and arteriolar volume, resulting in the restoration of local blood flow and thus the MRI signal once the transit of a bolus with reduced deoxyhemoglobin concentration across the local cerebral vasculature is completed. Therefore, the temporal resolution of BOLD fMRI is limited by the transit times through the vasculature. In humans, the full width at half maximum (FWHM) of the BOLD response is about 4 -6 s (5-8). In BOLD fMRI experiments that suppress the macrovascular contribution, the resolution can be improved to 3-4 s FWHM (9).In humans, there is evidence for a faster increase in CBF than in BOLD in response to focal brain activation (10). However, most of the data assessing the early aspects of the temporal response of hemodynamic signals have been obtained in rat somatosensory cortex. It has been shown that CBF increases before BOLD (11). In addition, measurements of CBV using iron-oxide-based contrast also have shown faster onset responses than BOLD (12,13), even though CBV takes longer to reach steady state (14). These studies were all performed using long stimuli and did not characterize the response to short...

show abstract

“…For example, the temporal resolving power of the GRE BOLD has been reported to be superior to the SE BOLD in visual cortex, although the latter exhibited earlier TTP (Hulvershorn et al, ). Another study found that perfusion‐based fMRI performed better than the GRE BOLD in detecting temporal differences between visual and auditory cortices (Liu et al, , pp. 111–117), although the former had lower contrast‐to‐noise ratio (CNR).…”

Section: Introductionmentioning

confidence: 99%

“…Advances in functional magnetic resonance imaging (fMRI) techniques have greatly enhanced our understanding toward functional organizations of the human brain (Menon et al, ; Hulvershorn et al, , , pp. 247–258; Liu et al, ; Smirnakis et al, ). Conventional fMRI based on the blood oxygenation level‐dependent (BOLD) gradient‐recalled echo (GRE) signal measures regional variations in cerebral hemodynamics to infer the spatial localization of neural activity (Belliveau et al, ; Kwong et al, ; Ogawa et al, ).…”

Section: Introductionmentioning

confidence: 99%

Variations in BOLD response latency estimated from event‐related fMRI at 3T: Comparisons between gradient‐echo and Spin‐echo

Yeh¹,

Kuan³

et al. 2013

Int J Imaging Syst Tech

Self Cite

View full text Add to dashboard Cite

Functional magnetic resonance imaging (fMRI) commonly uses gradient-recalled echo (GRE) signals to detect regional hemodynamic variations originating from neural activities. While the spatial localization of activation shows promising applications, indexing temporal response remains a poor mechanism for detecting the timing of neural activity. Particularly, the hemodynamic response may fail to resolve sub-second temporal differences between brain regions because of its signal origin or noise in data, or both. This study aimed at evaluating the performance of latency estimation using different fMRI techniques, with two event-related experiments at 3T. Experiment I evaluated latency variations within the visual cortex and their relationship with contrast-to-noise ratios (CNRs) for GRE, spin echo (SE), and diffusion-weighted SE (DWSE). Experiment II used delayed visual stimuli between two hemifields (delay time 5 0, 250, and 500 ms, respectively) to assess the temporal resolving power of three protocols: GRE TR1000 , GRE TR500 , and SE TR1000 . The results of experiment I showed the earliest latency with DWSE, followed by SE, and then GRE. Latency variations decreased as CNR increased. However, similar variations were found between GRE and SE, when the latter had lower CNR. In experiment II, measured stimulus delays from all conditions were significantly correlated with preset stimulus delays. Inter-subject variation in the measured delay was found to be greatest with GRE TR1000 , followed by GRE TR500 , and the least with SE TR1000 . Conclusively, blood oxygenation level-dependent responses obtained from GRE exhibit greater CNR but no compromised latency variations in the visual cortex. SE is potentially capable of improving the performance of latency estimation, especially for group analysis.

show abstract

Disparity of activation onset in sensory cortex from simultaneous auditory and visual stimulation: Differences between perfusion and blood oxygenation level‐dependent functional magnetic resonance imaging

Cited by 5 publications

References 30 publications

fMRI hemodynamics accurately reflects neuronal timing in the human brain measured by MEG

fMRI hemodynamics accurately reflects neuronal timing in the human brain measured by MEG

Functional MRI impulse response for BOLD and CBV contrast in rat somatosensory cortex

Variations in BOLD response latency estimated from event‐related fMRI at 3T: Comparisons between gradient‐echo and Spin‐echo

Contact Info

Product

Resources

About