The data displayed on this page was collected using Electromagnetic Articulography (EMA) and Electropalatography (EPG), two techniques which give direct measures of articulation.

EPG Palate

EMA subject

Electropalatography (EPG) uses a thin artificial palate to measure tongue-palate contact during an utterance. Contact of the tongue with any of the 62 electrodes embedded in the palate completes an electrical circuit, and tongue-palate contact is registered. The system used was developed at Reading.

In Electromagnetic Articulography (EMA) electromagnetic transducers, mounted in a helmet worn by the subject, induce a current in small coils placed on the articulators. The strength of the current is used to calculate the position of the articulators. The picture shows a subject wearing the Carstens AG100 Articulograph helmet and the artificial palate displayed. Coils are mounted on the subject's tongue and the bridge of his nose.

The sentence "Have you uttered a leap at home?" was produced by the male speaker of standard Southern British English shown above. The picture on the left below (EMA Profile) shows a trace of the subject's hard palate and the trajectories followed by the EMA coils during the utterance. The right-hand picture shows the waveform of the utterance over time and the movement of each of the coils in the x and y directions separately (colour-coded to match the trajectories).

EMA trajectories EMA coils and waveform display

This data was collected as part of research on long-distance coarticulation by Paula West.

P. West, Oxford University Phonetics Lab, 11/1998

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