Subcortical fMRI signals are degraded by cardiac pulsatile motion effects

Evidence

At low frequencies it is assumed that the subject produces his/her own noise as a consequence of the blood supply in the inner ear and of vibrations produced by the heart and muscles. We adapt to this noise because it is always there and therefore we don’t usually hear it, particularly in our normal surroundings. This kind of internal noise is especially strong at low frequencies. At medium and high frequencies there may be noise produced in the neural processing. — Professor Dr.-Ing. Hugo Fastl, Professor Dr.-Ing. Eberhard, Psychoacoustics- Facts and Models, 1148 (#corroborates, via linked claim)

Categorization

• corroborated: 2 independent passages support this claim
• XREF: connects to: fMRI measures slow metabolic changes and is noisy, complicating auditory research; Internal physiological noise from blood flow and heartbeat raises low-frequency thresholds — Professor Dr.-Ing. Hugo Fastl, Professor Dr.-Ing. Eberhard, Psychoacoustics- Facts and Models, 1148

Related

• Internal physiological noise from blood flow and heartbeat raises low-frequency thresholds (similarity 0.87)
• Resting-state connectivity analysis must filter physiological noise that inflates correlations (similarity 0.86)
• Small subcortical auditory structures suffer poor fMRI signal noise (similarity 0.84)
• fMRI measures slow metabolic changes and is noisy, complicating auditory research (similarity 0.83)
• Subcortical BOLD reflects loudness slightly more than intensity, but noise is severe (similarity 0.83)
• Subcortical auditory structures encode sound intensity linearly while cortex compresses it. (similarity 0.82)
• Internal body noise, dominated by heartbeats and muscles, masks quiet sounds at low frequencies. (similarity 0.82)
• fMRI can map how sound intensity and loudness interact across the auditory pathway (similarity 0.82)
• Loudness growth is linear up to 80 dB then steepens near 90 dB (similarity 0.81)
• Internal bodily noise raises the hearing threshold at low frequencies (similarity 0.80)
• Inner-ear blood-flow noise is adapted out because it never stops (similarity 0.79)
• fMRI identifies active brain regions well but is noisy and time-slow for auditory study. (similarity 0.79)
• Noise harms the cardiovascular system even without disturbing sleep (similarity 0.79)
• Narrow-band noise produces substantial loudness in critical-band regions where no physical sound exists (similarity 0.79)

Broader Connections

• Internal physiological noise from blood flow and heartbeat raises low-frequency thresholds #corroborates (0.85) — Professor Dr.-Ing. Hugo Fastl, Professor Dr.-Ing. Eberhard, Psychoacoustics- Facts and Models, 1148