As video has become the dominant mode of content on platforms such as YouTube, TikTok, and Instagram, captioning has emerged as a critical factor for accessibility, engagement, and visibility. While prior studies have examined different types of social media video captions or communities’ captioning usage, a systematic synthesis has not been undertaken, leading to the risk of proposing interventions that overlook core platform constraints or miss critical accessibility needs. This paper reviews 36 peer-reviewed papers published between 2015 and 2025 across fields such as Human-Computer Interaction (HCI), accessibility, media studies, education, and language learning. We note that captions operate as collective infrastructure co-produced by viewers, creators, and platforms. Deaf and Hard of Hearing (DHH), neurodivergent, and multilingual viewers depend on captions and increasingly expect mechanisms for feedback, while creators face inadequate tool support. Building on these insights, we propose the framework of Participatory Captioning and suggest design implications, highlighting future directions for social media video caption research.

Recruiting participants from disability communities for accessibility research presents unique challenges that require careful consideration of ethical practices, intersectional representation, methodological rigor, and community sustainability.As accessibility research continues to grow and evolve, researchers face tensions between meaningfully including participants with disabilities and addressing emerging concerns around recruited participants not adequately representing the diversity of the community, overburdening certain participants, participant verification, and fair compensation practices.This workshop will bring together members of the ASSETS community to examine current recruiting practices and document insights into ethical, rigorous, and inclusive participant recruitment in disability research.Through facilitated discussions, we will explore three main themes: (1) methods and models, (2) eligibility criteria and participant verification, and (3) ethical and sustainability considerations.The workshop aims to share current practices, identify key challenges, and develop preliminary guidelines to support accessibility researchers in more sustainable participant recruitment.

Figure 1: Multimodal afective captions, combining visual cues and vibrations felt via a wrist-worn device, enrich the viewing experience for d/Deaf or Hard-of-Hearing individuals by portraying speaker emotions, improving engagement.

Closed-captioning is an essential part of viewing audio-visual content for many people, including those who are D/deaf and Hard-of-Hearing. Traditional closed-captioning systems generally consist of a single track of timed text that offers limited options for personalization. Research into extending the capabilities of captioning, such as affective, poetic, and customizable captions has shown a desire among a subset of users for these features, but only in specific contexts. However, due to the difficulty in creating custom stimuli videos utilizing the custom captioning system, comparisons between systems and longitudinal studies have not been pursued. This demo paper introduces Rich Captions, a structured system that allows for a single closed-caption file to be tagged with additional information that can then be flexibly leveraged to render different customizable, creative, and poetic captions from the same file. Additionally, we introduce the Rich Caption Editor 1, a free, open-source software system designed to author, edit, and render rich captions. The system design was informed by a formative design workshop with closed-captioning researchers and advocates. The current design allows researchers to generate reproducible stimuli for closed-captioning studies. Once the design space and user preferences are better understood, the rich captioning framework could be refined to serve a general audience.

High-quality closed captioning of both speech and non-speech elements (e.g., music, sound effects, manner of speaking, and speaker identification) is essential for the accessibility of video content, especially for d/Deaf and hard-of-hearing individuals. While many regions have regulations mandating captioning for television and movies, a regulatory gap remains for the vast amount of web-based video content, including the staggering 500+ hours uploaded to YouTube every minute. Advances in automatic speech recognition have bolstered the presence of captions on YouTube. However, the technology has notable limitations, including the omission of many non-speech elements, which are often crucial for understanding content narratives. This paper examines the contemporary and historical state of non-speech information (NSI) captioning on YouTube through the creation and exploratory analysis of a dataset of over 715k videos. We identify factors that influence NSI caption practices and suggest avenues for future research to enhance the accessibility of online video content.

The communication of non-speech information (NSI) in closed captioning is essential in providing full access and increased enjoyment of video content, particularly for d/Deaf or Hard-of-Hearing (DHH) viewers. We identified the limitations and frustrations of current NSI captioning through needfinding interviews and then employed a critical design framework to develop a medium-fidelity audio-reactive animated overlay prototype to explore the opinions and values of DHH users regarding NSI communication through surveys and interviews. The results show that current NSI captioning strategies lack consistency across platforms, adequate temporal information, clarity in emotional conveyance, and lack customization options. The study suggests that novel sound communication technologies show promise in enhancing certain aspects NSI communication and that there is a strong desire to move beyond the current, inflexible format of single-track closed captions for NSI communication.

The inclusion of voice persona in synthesized voice can be significant in a broad range of human-computer-interaction (HCI) applications, including augmentative and assistive communication (AAC), artistic performance, and design of virtual agents. We propose a framework to imbue compelling and contextually-dependent expression within a synthesized voice by introducing the role of the vocal persona within a synthesis system. In this framework, the resultant ‘tone of voice’ is defined as a point existing within a continuous, contextually-dependent probability space that is traversable by the user of the voice. We also present initial findings of a thematic analysis of 10 interviews with vocal studies and performance experts to further understand the role of the vocal persona within a natural communication ecology. The themes identified are then used to inform the design of the aforementioned framework.