Shared Neural Mechanisms for the Prediction of Own and Partner Musical Sequences after Short-term Piano Duet Training

Short-term plasticity of neuro-auditory processing induced by musical active listening training

Although there is strong evidence for the positive effects of musical training on auditory perception, processing, and training-induced neuroplasticity, there is still little knowledge on the auditory and neurophysiological short-term plasticity through listening training. In a sample of 37 adolescents (20 musicians and 17 nonmusicians) that was compared to a control group matched for age, gender, and musical experience, we conducted a 2-week active listening training (AULOS: Active IndividUalized Listening OptimizationS). Using magnetoencephalography and psychoacoustic tests, the short-term plasticity of auditory evoked fields and auditory skills were examined in a pre-post design, adapted to the individual neuro-auditory profiles. We found bilateral, but more pronounced plastic changes in the right auditory cortex. Moreover, we observed synchronization of the auditory evoked P1, N1, and P2 responses and threefold larger amplitudes of the late P2 response, similar to the reported effects of musical long-term training. Auditory skills and thresholds benefited largely from the AULOS training. Remarkably, after training, the mean thresholds improved by 12 dB for bone conduction and by 3-4 dB for air conduction. Thus, our findings indicate a strong positive influence of active listening training on neural auditory processing and perception in adolescence, when the auditory system is still developing.

Benefits of choir singing on complex auditory encoding in the aging brain: An ERP study

Aging is accompanied by difficulties in auditory information processing, especially in more complex sound environments. Choir singing requires efficient processing of multiple sound features and could, therefore, mitigate the detrimental effects of aging on complex auditory encoding. We recorded auditory event-related potentials during passive listening of sounds in healthy older adult (≥ 60 years) choir singers and nonsinger controls. We conducted a complex oddball condition involving encoding of abstract regularities in combinations of pitch and location features, as well as in two simple oddball conditions, in which only either the pitch or spatial location of the sounds was varied. We analyzed change-related mismatch negativity (MMN) and obligatory P1 and N1 responses in each condition. In the complex condition, the choir singers showed a larger MMN than the controls, which also correlated with better performance in a verbal fluency test. In the simple pitch and location conditions, the choir singers had smaller N1 responses compared to the control subjects, whereas the MMN responses did not differ between groups. These results suggest that regular choir singing is associated both with more enhanced encoding of complex auditory regularities and more effective adaptation to simple sound features.

Cerebellar contributions to sequence prediction in verbal working memory

Verbal working memory is one of the most studied non-motor functions with robust cerebellar involvement. While the superior cerebellum (lobule VI) has been associated with articulatory control, the inferior cerebellum (lobule VIIIa) has been linked to phonological storage. The present study was aimed to elucidate the differential roles of these regions by investigating whether the cerebellum might contribute to verbal working memory via predictions based on sequence learning/detection. 19 healthy adult subjects completed an fMRI-based Sternberg task which included repeating and novel letter sequences that were phonologically similar or dissimilar. It was hypothesized that learning a repeating sequence of study letters would reduce phonological storage demand and associated right inferior cerebellar activations and that this effect would be modulated by phonological similarity of the study letters. Specifically, while increased phonological storage demand due to high phonological similarity was expected to be reflected in increased right inferior cerebellar activations for similar relative to dissimilar study letters, the reduction in activation for repeating relative to novel sequences was expected to be more profound for phonologically similar than for dissimilar study letters, especially at higher memory load. Results confirmed the typical effects of cognitive load (5 vs. 2 study letters) and phonological similarity in several cerebellar and neocortical brain regions as well as in behavioral data (accuracy and response time). Importantly, activations in superior and inferior cerebellar regions were differentially modulated as a function of similarity and sequence novelty, indicating that particularly lobule VIIIa may contribute to verbal working memory by generating predictions of letter sequences that reduce the likelihood of phonological loop failure before stored items need to be retrieved. The present study is consistent with other investigations that support prediction, which can be based on sequence learning or detection, as an overarching cerebellar function.