Acoustic, psychophysical, and neuroimaging measurements of the effectiveness of active cancellation during auditory functional magnetic resonance imaging
| Autor: | Alan R. Palmer, Deborah A. Hall, Ron Coxon, John R. Foster, Michael A. Akeroyd, John Chambers |
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| Rok vydání: | 2009 |
| Předmět: |
Adult
Male Auditory perception Adolescent Acoustics and Ultrasonics Computer science Microphone Auditory response Noise reduction Acoustics Perceptual Masking Young Adult Arts and Humanities (miscellaneous) Neuroimaging Psychophysics otorhinolaryngologic diseases medicine Humans Active listening Sound pressure Active noise control medicine.diagnostic_test Auditory Threshold Magnetic Resonance Imaging Sound Auditory Perception Female Functional magnetic resonance imaging Electromagnetic Phenomena Acoustic attenuation |
| Zdroj: | Journal of the Acoustical Society of America |
| ISSN: | 0001-4966 |
| Popis: | Functional magnetic resonance imaging (fMRI) is one of the principal neuroimaging techniques for studying human audition, but it generates an intense background sound which hinders listening performance and confounds measures of the auditory response. This paper reports the perceptual effects of an active noise control (ANC) system that operates in the electromagnetically hostile and physically compact neuroimaging environment to provide significant noise reduction, without interfering with image quality. Cancellation was first evaluated at 600 Hz, corresponding to the dominant peak in the power spectrum of the background sound and at which cancellation is maximally effective. Microphone measurements at the ear demonstrated 35 dB of acoustic attenuation [from 93 to 58 dB sound pressure level (SPL)], while masked detection thresholds improved by 20 dB (from 74 to 54 dB SPL). Considerable perceptual benefits were also obtained across other frequencies, including those corresponding to dips in the spectrum of the background sound. Cancellation also improved the statistical detection of sound-related cortical activation, especially for sounds presented at low intensities. These results confirm that ANC offers substantial benefits for fMRI research. |
| Databáze: | OpenAIRE |
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