Structural and Functional Changes in the Brain Caused by Short-term Pitch Discrimination Training

Abstract

Background Pitch discrimination learning has been shown to enhance psychoacoustic performance, which is hypothesised to be supported by structural and functional changes in the brain. Several investigations have shown that long-term auditory training positively impact on brain function and morphology; for instance, proficient musicians show neuroplastic alterations of the brain. However, only a few studies have investigated the effects of short-term auditory training on neuroplasticity. Method: The first study investigated the effects on neural plasticity in auditory areas that were associated with short-term training in pitch discrimination over three consecutive days across musical novices (n=26), and the second study compared these effects with those caused by long-term experiences among proficient musicians (n=11). Another target of the current study was to explore the effect of pitch discrimination learning on hemispheric lateralisation of functional activity by presenting different acoustic stimuli. These study targets were achieved through use of a combination of functional (task-based fMRI) and structural (T1w and DTI)imaging as psychoacoustic performance was monitored. A battery of quantitative image analysis methods was employed. Result: One of this project’s main findings is that short-term auditory training causes significant functional and structural changes in the auditory areas. These changes are most prominent in the superior temporal gyrus and the right white-matter pathways, including the corticospinal tract and corona radiata. The changes were noticed to occur in parallel with progress in psychoacoustic performance. Project’s findings are in line with differences that have been observed in proficient musicians compared with novices. The results also reveal hemispheric lateralisation in functional activity within auditory regions affected by musical practice levels. Discussion: The project outcome makes a significant contribution to knowledge regarding short-term pitch discrimination learning, which will help to expand the understanding of changes in brain plasticity with learning.