title: Auditory steady-state responses to 40-Hz click trains: relationship to middle latency, gamma band and beta band responses studied with deconvolution.
abstract: OBJECTIVE
  The nature of the auditory steady-state responses (ASSR) evoked with 40-Hz click trains and their relationship to auditory brainstem and middle latency responses (ABR/MLR), gamma band responses (GBR) and beta band responses (BBR) were investigated using superposition theory. Transient responses obtained by continuous loop averaging deconvolution (CLAD) and last click responses (LCR) were used to synthesize ASSRs and GBRs.
  
  
  METHODS
  ASSRs were obtained with trains of low jittered 40 Hz clicks presented monaurally and deconvolved using a modified CLAD. Resulting transient responses and modified LCRs were used to predict the ASSRs and the GBR.
  
  
  RESULTS
  The ABR/MLR obtained with deconvolution predicted accurately the steady portion of the ASSR but failed to predict its onset portion. The modified LCR failed to fully predict both portions. The GBRs were predicted by narrow band filtering of the ASSRs. Significant BBR activity was found both in the ASSRs and deconvolved ABR/MLRs.
  
  
  CONCLUSIONS
  Simulations using deconvolved ABR/MLRs obtained at 40 Hz predict fully the steady state but not the onset portion of the ASSRs, thus confirming the superposition theory.
  
  
  CONCLUSIONS
  Click rate adaptation plays a significant role in ASSR generation with click trains and should be considered in evaluating convolved response generation theories.
authors.affiliation: Department of Biomedical Engineering, University of Miami, Coral Gables, FL 33146, USA.
authors.forename: Alessandro
authors.initials: A
authors.lastname: Presacco
authors.affiliation: Department of Biomedical Engineering, University of Miami, Coral Gables, FL 33146, USA.
authors.forename: Jorge
authors.initials: J
authors.lastname: Bohórquez
authors.affiliation: Department of Biomedical Engineering, University of Miami, Coral Gables, FL 33146, USA; Intelligent Hearing Systems Inc., Miami, FL 33143, USA.
authors.forename: Erdem
authors.initials: E
authors.lastname: Yavuz
authors.affiliation: Department of Biomedical Engineering, University of Miami, Coral Gables, FL 33146, USA; Department of Otolaryngology, Pediatrics and Neuroscience Program (Graduate), Miller School of Medicine, University of Miami, Miami, FL 33146, USA. Electronic address: oozdamar@miami.edu.
authors.forename: Özcan
authors.initials: Ö
authors.lastname: Özdamar
mesh_terms: D000161:Acoustic Stimulation / Q000379:methods; D000328:Adult; D001307:Auditory Perception / Q000502:physiology*; D003265:Contingent Negative Variation / Q000502:physiology*; D004569:Electroencephalography / Q000379:methods; D005072:Evoked Potentials, Auditory / Q000502:physiology*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D011930:Reaction Time / Q000502:physiology*; D013997:Time Factors