# Melody transposition tolerance in the human cortex: An fMRI adaptation and MVPA investigation

## TL;DR

The study found brain regions that recognize melodies even when they are transposed, suggesting a neural basis for melody tolerance.

## Contribution

The study identifies specific brain regions that show tolerance to melody transposition using fMRI adaptation and MVPA techniques.

## Key findings

- Brain regions in the right STG and left MTG showed adaptation to same and transposed melodies.
- BOLD patterns in several regions, including PreCG and IFG, exhibited tolerance to melody transposition.
- Tolerance to melody transposition spans from auditory to motor cortices in the brain.

## Abstract

Melody perception involves constant relational representations, enabling most people to recognize the melodies after being transposed. This invariant property of melody transposition has been supported in many previous behavioral studies, and we hypothesize that there are brain regions showing tolerance toward melody transposition when processing melodies. To test the hypothesis, we adopted an event-related adaptation approach and a multivariate pattern cross-classification (MVCC) analysis approach. Consistent with our prediction, we discovered clusters in the right superior temporal gyrus (STG) and the left middle temporal gyrus (MTG) that exhibited adaptation when participants listened to both the same and transposed-same melodies after the original ones. An ROI and searchlight-based cross-classification analysis also revealed that BOLD pattern in the bilateral precentral gyrus (PreCG), the left inferior frontal gyrus (IFG), the left inferior parietal lobule (IPL), the right angular gyrus (AG), and the right superior temporal gyrus (STG) showed tolerance to melody transposition. These findings suggest that tolerance to melody transposition exists throughout the music processing pathway from auditory to motor cortices.