Alpha and Theta EEG Variations as Indices of Listening Effort to Be Implemented in Neurofeedback Among Cochlear Implant Users

Theta and Alpha EEG rhythms appear useful for the listening effort estimation. In particular, Alpha would inhibit irrelevant stimuli, and Theta underlies working memory and processing. The balance between them seems essential for the word recognition, therefore evaluating the listening effort experienced by hearing impaired patients appears worthy, since noise/distortions in a speech signal increase listening effort. Aim of the study was the estimation of the effort during word in noise recognition under different noise conditions, and along the task. Results showed an increase in the frontal Theta and parietal Alpha for a difficult (but not the most difficult) noise condition, and for Theta in correspondence of the stimulus. Additionally, frontal Theta activity increased along the task for the same difficult noise condition during and after the stimulus.