From phys.org: 1,500 ultrasound tongue recordings reveals secrets of our accents.

Phonetics experts have completed a project to reveal the hidden workings of our tongues and vocal tracts using 1,500 ultrasound videos. The unique corpus of ultrasound videos was compiled as part of a research project looking at how speakers of different accents move their tongue and lips.

Researchers on the Dynamic Dialects project, led from the University of Glasgow used Ultrasound Tongue Imaging equipment to reveal how the hidden mechanics of our lips and tongues, combine to produce the distinct accents from different speakers of English around the world.

The most extensive study of its kind, the project looked at native English speakers from 48 regions and 16 different countries around the world, building up a comprehensive picture of how and why different accents of English are distinct from one another. [continue]