title: Objective detection of auditory steady-state evoked potentials based on mutual information.
abstract: OBJECTIVE
  Recently, we developed a metric to objectively detect human auditory evoked potentials based on the mutual information (MI) between neural responses and stimulus spectrograms. Here, the MI algorithm is evaluated further for validity in testing the auditory steady-state response (ASSR), a sustained potential used in objective audiometry.
  
  
  METHODS
  MI was computed between spectrograms of ASSRs and their evoking stimuli to quantify the shared time-frequency information between neuroelectric activity and stimulus acoustics. MI was compared against two traditional ASSR detection metrics: F-test and magnitude-squared coherence (MSC).
  
  
  METHODS
  Using an empirically derived threshold (⊖MI=1.45), MI was applied as a binary classifier to distinguish actual biological responses recorded in human participants (n=11) from sham recordings, containing only EEG noise (i.e., non-stimulus-control condition).
  
  
  RESULTS
  MI achieved high overall accuracy (>90%) in identifying true ASSRs from sham recordings, with true positive/true negative rates of 82/100%. During online averaging, comparison with two other indices (F-test, MSC) indicated that MI could detect ASSRs in roughly half the number of trials (i.e., ∼400 sweeps) as the MSC and performed comparably to the F-test, but showed slightly better signal detection performance.
  
  
  CONCLUSIONS
  MI provides an alternative, more flexible metric for efficient and automated ASSR detection.
authors.affiliation: a Institute for Intelligent Systems, University of Memphis , Memphis , TN , USA and.|b School of Communication Sciences & Disorders , University of Memphis , Memphis , TN , USA.
authors.forename: Gavin M
authors.initials: GM
authors.lastname: Bidelman
authors.affiliation: b School of Communication Sciences & Disorders , University of Memphis , Memphis , TN , USA.
authors.forename: Shaum P
authors.initials: SP
authors.lastname: Bhagat
mesh_terms: D000161:Acoustic Stimulation / Q000379:methods*; D000328:Adult; D000465:Algorithms; D001300:Audiometry, Evoked Response / Q000379:methods*; D001309:Auditory Threshold; D005072:Evoked Potentials, Auditory; D005260:Female; D064368:Healthy Volunteers; D006801:Humans; D008297:Male; D015203:Reproducibility of Results; D055815:Young Adult
keywords: Auditory evoked potentials (AEPs); F-test. Magnitude-squared coherence (MSC); automated auditory brainstem response (AABR); evoked potential classification; objective audiometry