Neural correlates of individual differences in predicting ambiguous sounds comprehension level.

This study investigated brain activation during auditory processing as a biomarker for the prediction of future perceptual learning performance. Cochlear implant simulated sounds (vocoded sounds) are degraded signals. Participants with normal hearing who were trained with these ambiguous sounds showed varied speech comprehension levels. We discovered that the neuronal signatures from untrained participants forecasted their future ambiguous speech comprehension levels. Participants' brain activations for auditory information processing were measured before (t1) they underwent a five-day vocoded sounds training session. We showed that the pre-training (t1) activities in the inferior frontal gyrus (IFG) correlate with the fifth-day (t2) vocoded sound comprehension performance. To further predict participants' future (t2) performances, we split the participants into two groups (i.e., good and bad learners) based on their fifth-day performance; a linear support vector machine (SVM) was trained to classify (predict) the remaining participants' groups. We found that pre-training (t1) fMRI activities in the bilateral IFG, angular gyrus (AG), and supramarginal gyrus (SMG) showed discriminability between future (t2) good and bad learners. These findings suggest that neural correlates of individual differences in auditory processing can potentially be used to predict participants' future cognition and behaviors.