DOI: 10.17026/ss/cnqgsy
title: NGT video stimuli, with and without mouth actions

description: This repository consists of 908 high-quality videos in .mov format of single signs in Nederlandse Gebarentaal (NGT); i.e., Dutch Sign Language, also called Sign Language of the Netherlands. These NGT signs were created as experimental stimuli for a study led by principal investigator, Ellen Ormel (Radboud University). The sign model in all videos is Ms. Merel van Zuilen, who is filmed with a dark long-sleeved shirt on a plain blue background. The video file sizes range from 16 megabytes to over 40 megabytes. &lt;br&gt;&lt;br&gt;

There are two overall types of videos as part of the experimental design: (1) those in which the manual sign is accompanied by a mouth action (449 videos) and (2) those articulated without any mouth action (459 videos). "Mouth action" refers to both "mouthings" that map to the articulations in a spoken word and "mouth gestures" that are linguistic elements that accompany the movement of the hands and body. All together, there are 425 unique manual signs in the dataset and most of these manual signs have both types of videos: a manual sign with a mouth action and the same manual sign without a mouth action. There are also phonetic variants on some signs, which increases the overall number of videos. &lt;br&gt; &lt;br&gt;

The filenaming convention for the files is as follows. The filename starts with a gloss translation in Dutch in capital letters (e.g., APPEL) followed by an optional dash separator and letter to indicate a lexical variant (e.g., KROON-A, KROON-B), followed by an optional underscore and number to indicate a phonetic variant (e.g., ONTDOOIEN_1, ONTDOOIEN_2, PRATEN-A_1, PRATEN-A_2), followed by an obligatory underscore and two-letter code for the mouth actions status of the sign: MM, GM, or ZM. 'MM' for &lt;i&gt;met mondbeeld&lt;/i&gt; indicates a mouthing that typically mirrors a spoken word in Dutch; 'GM' for &lt;i&gt;gesture mondbeeld&lt;/i&gt; indicates a mouth gesture (including mouth morphemes); and ZM for &lt;i&gt; zonder mondbeeld &lt;/i&gt; indicates no mouth action at all. For example, AARDBEI_MM.mov is a video of the NGT sign for strawberry (&lt;i&gt;aardbei&lt;/i&gt;) produced with mouthing, while KAMMEN-A_1_ZM.mov is a video of the first phonetic type of the lexical variant A of the sign for to comb/combing (&lt;I&gt;kammen&lt;/i&gt;) and is produced without mouth movement. &lt;br&gt; &lt;br&gt;

Four other documents are in the repository: (1) an Excel spreadsheet showing the 425 unique manual NGT signs with index number, Dutch gloss, indication of a matching sign in the NGT dataset in Global Signbank (https://signbank.cls.ru.nl), the number of sub-variants, whether there is a video with and without a mouth action, and the total number of videos associated with the manual sign; (2) an 8-page PDF of the Excel spreadsheet; (3) a comma-delimited document [original format] that lists all video filenames for those signs with a mouth action (NGT_Signs_With_Mouth_Action-MM_GM_449signs.csv); (4) a comma-delimited document [original format] that lists all video filenames for those signs without any mouth action (NGT_Signs_Without_Mouth_Action_ZM_459signs.csv). Tags are applied to each document type for custom searches: &lt;i&gt;Data&lt;/i&gt;, &lt;i&gt;Documentation&lt;/i&gt;, &lt;i&gt;+mouth&lt;/i&gt;, &lt;i&gt;-mouth&lt;/i&gt;, &lt;i&gt;mouth_gesture&lt;/i&gt;.
description: The filenames for each video contain a Dutch word that is a relatively close translation — a "gloss" — of the sign meaning in NGT. These glosses were made to match the unique Lemma ID Gloss in the NGT dataset in Global Signbank, located here: https://signbank.cls.ru.nl/datasets/NGT. The glosses in the filenames in this repository were cross-checked with SignBank as recently as January 2024; however, users should be aware that these names may diverge over time.