Interpreting the BOLD Signal
Annual Review of PhysiologyPublished 11 February 2004
Nikos K. Logothetis, Brian A. Wandell
Citations1,589
SJR quartileQ1
SJR score7.82
SNIP4.62
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TL;DR
The current understanding of the causal relationships between neural activity and the blood-oxygen-level-dependent (BOLD) signal is described, and how these analyses have challenged some basic assumptions that have guided neuroscience are reviewed.
Abstract
The development of functional magnetic resonance imaging (fMRI) has brought together a broad community of scientists interested in measuring the neural basis of the human mind. Because fMRI signals are an indirect measure of neural activity, interpreting these signals to make deductions about the nervous system requires some understanding of the signaling mechanisms. We describe our current understanding of the causal relationships between neural activity and the blood-oxygen-level-dependent (BOLD) signal, and we review how these analyses have challenged some basic assumptions that have guided neuroscience. We conclude with a discussion of how to use the BOLD signal to make inferences about the neural signal.
Keywords
MedicineNeuroscience
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NeuroImageMeasurements of the Temporal fMRI Response of the Human Auditory Cortex to Trains of Tones
181 Citations1998Matthew D. Robson, Jennifer L. Dorosz +1 more
It was found, with the aid of computer simulation that a sampling rate of one image per second is adequate to distinguish temporal responses, and the temporal response to 700-ms tone stimuli is modified when performed in the presence of scanner gradient noise.
The Journal of PhysiologyDelayed depolarization and the repetitive response to intracellular stimulation of mammalian motoneurones
176 Citations1963Raǵnar Granit, Daniel Kernell +1 more
The present work was undertaken in order to investigate quantitative and qualitative aspects of tonic firing of motoneurones by the intracellular technique, being in this respect a sequence to studies of maintained unit discharges in ventral roots pursued over some years.
Echo-Planar Imaging: Theory, Technique and Application
175 Citations2012Franz Schmitt, Michael K. Stehling +2 more
E Echo-Planar Magnetic Resonance Imaging of Human Brain Activation and its Applications: Clinical Applications of Neuroimaging Using Echo- planar Imaging and Research Issues using Echo-planar Imaging for Functional Brain Imaging.
Proceedings of the National Academy of SciencesFunctional MRI at 1.5 tesla: A comparison of the blood oxygenation level-dependent signal and electrophysiology
174 Citations2000Elizabeth A. Disbrow, Daniel A. Slutsky +2 more
It is shown that fMRI can be used to determine the topographic organization of cortical fields with 55% concordance to electrophysiological maps and the variance in the location of fMRI activation was greatest in the plane perpendicular to local vessels.
Journal of NeurophysiologyInterhemispheric Transmission of Visuomotor Information in Humans: fMRI Evidence
159 Citations2002Marco Tettamanti, Eraldo Paulesu +5 more
The aim of the experiment was to test the hypothesis that IT of visuomotor information requires the corpus callosum and to identify the cortical areas specifically activated during IT, and to discover whether IT occurs mainly at premotor or perceptual stages of information processing.
Experimental Brain ResearchVisual stimulation elicits locked and induced gamma oscillations in monkey intracortical- and EEG-potentials, but not in human EEG
157 Citations1999Egbert Juergens, Andreas Guettler +1 more
It is concluded that visually evoked γ-modulations in humans EEG are not as accessible as in the monkey, and stimulus-relatedγ-Modulation in human subjects contradicts several published findings.
Proceedings of the National Academy of SciencesInterpreting functional imaging studies in terms of neurotransmitter cycling
153 Citations1998Robert G. Shulman, Douglas L. Rothman
The quantitation of neuronal activity proposed has implications for the psychological design and interpretation of functional imaging experiments and neurobiological processes responsible for the signals.
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