title: Effects of scanner acoustic noise on intrinsic brain activity during auditory stimulation.
abstract: BACKGROUND
  Although the effects of scanner background noise (SBN) during functional magnetic resonance imaging (fMRI) have been extensively investigated for the brain regions involved in auditory processing, its impact on other types of intrinsic brain activity has largely been neglected. The present study evaluated the influence of SBN on a number of intrinsic connectivity networks (ICNs) during auditory stimulation by comparing the results obtained using sparse temporal acquisition (STA) with those using continuous acquisition (CA).
  
  
  METHODS
  Fourteen healthy subjects were presented with classical music pieces in a block paradigm during two sessions of STA and CA. A volume-matched CA dataset (CAm) was generated by subsampling the CA dataset to temporally match it with the STA data. Independent component analysis was performed on the concatenated STA-CAm datasets, and voxel data, time courses, power spectra, and functional connectivity were compared.
  
  
  RESULTS
  The ICA revealed 19 ICNs; the auditory, default mode, salience, and frontoparietal networks showed greater activity in the STA. The spectral peaks in 17 networks corresponded to the stimulation cycles in the STA, while only five networks displayed this correspondence in the CA. The dorsal default mode and salience networks exhibited stronger correlations with the stimulus waveform in the STA.
  
  
  CONCLUSIONS
  SBN appeared to influence not only the areas of auditory response but also the majority of other ICNs, including attention and sensory networks. Therefore, SBN should be regarded as a serious nuisance factor during fMRI studies investigating intrinsic brain activity under external stimulation or task loads.
authors.affiliation: Institute of Medical Science, School of Medicine, Kangwon National University, Chuncheon, Republic of Korea.|Neuroscience Research Institute, Kangwon National University Hospital, Chuncheon, Republic of Korea.
authors.forename: Natalia
authors.initials: N
authors.lastname: Yakunina
authors.affiliation: Department of Rehabilitation Medicine, Kangwon National University Hospital, Chuncheon, Republic of Korea.
authors.forename: Eun Kyoung
authors.initials: EK
authors.lastname: Kang
authors.affiliation: Department of Otolaryngology, Kangwon National University Hospital, Chuncheon, Republic of Korea.|Department of Otolaryngology, Kangwon National University, School of Medicine, Kangwondaehak-gil 1, Chuncheon, 200-701, Republic of Korea.
authors.forename: Tae Su
authors.initials: TS
authors.lastname: Kim
authors.affiliation: Department of Biopsychology, Cognition, and Neuroscience, University of Michigan, Ann Arbor, MI, USA.
authors.forename: Ji-Hoon
authors.initials: JH
authors.lastname: Min
authors.affiliation: Neuroscience Research Institute, Kangwon National University Hospital, Chuncheon, Republic of Korea.|Department of Radiology, Kangwon National University, School of Medicine, Chuncheon, Republic of Korea.
authors.forename: Sam Soo
authors.initials: SS
authors.lastname: Kim
authors.affiliation: Neuroscience Research Institute, Kangwon National University Hospital, Chuncheon, Republic of Korea. birdynec@kangwon.ac.kr.|Department of Otolaryngology, Kangwon National University, School of Medicine, Kangwondaehak-gil 1, Chuncheon, 200-701, Republic of Korea. birdynec@kangwon.ac.kr.
authors.forename: Eui-Cheol
authors.initials: EC
authors.lastname: Nam
mesh_terms: D000161:Acoustic Stimulation / Q000379:methods*; D000328:Adult; D001921:Brain / Q000502:physiology*; D005072:Evoked Potentials, Auditory / Q000502:physiology*; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000295:instrumentation* / Q000379:methods*; D008297:Male; D009415:Nerve Net / Q000502:physiology; D009622:Noise; D059629:Signal-To-Noise Ratio
keywords: Auditory stimulation; Functional MRI; Intrinsic connectivity network; Scanner background noise; Sparse temporal acquisition