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 work ing memory and processing. The balance between them seems essential for the word recognition, therefore evaluating the listening effort experienced by hear ing impaired patients appears worthy, since noise/distortions in a speech signal increase listening effort. Aim of the study was the estimation of the effort dur ing 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 corre spondence of the stimulus. Additionally, frontal Theta activity increased along the task for the same difficult noise condition during and after the stimulus. This evaluation was preliminary for a neurofeedback application of the effort management by CI users, since it could affect performances and attitudes. Such assessment appears extremely worthy of investigation since the symbiotic inter action between cochlear implant devices and deaf patients for the decoding and processing of the incoming auditory signal.