Whispering Through Walls: Towards Inclusive Backchannel Communication in Hybrid Meetings

Document Title

Whispering Through Walls: Towards Inclusive Backchannel Communication in Hybrid Meetings

Document Information

• Topic Area: Multimodal Collaboration and Hybrid Meeting Technologies
• Keywords: Backchannel Communication, Hybrid Meetings, Virtual Meetings, Whispering, Inclusivity, Cross-space Collaboration, Synchronous Communication, Human-Computer Interaction, Collaboration Technologies
• Conference: CHI 2024
• Authors: Qianqian Mu, Marcel Borowski, Jens Emil Grønbæk, Susanne Bødker, Eve Hoggan

Research Background and Issues

• Problems or Challenges:

  1. In hybrid meetings, backchannel communication (such as whispering or instant messaging) lacks inclusivity, particularly for remote participants who often struggle to engage equally.
  2. Current backchannel communication tools are predominantly text-based, and their asynchronous nature increases operational complexity and usage barriers for participants.
  3. The technological heterogeneity and physical distribution of participants in hybrid meetings lead to information asymmetry between remote and on-site users.

• Significance: Backchannel communication serves as an important supplementary method to foreground communication, fostering social connections, providing feedback, and enhancing engagement. However, due to the heterogeneity of hybrid meetings, this communication method is often unfriendly to certain participants (especially remote attendees), limiting collaboration efficiency and meeting dynamics.

• Research Motivation: The authors aim to explore backchannel communication in hybrid meetings and investigate how system design can address issues of inclusivity and high operational costs, creating more equitable participation conditions for both remote and on-site attendees.

• Related Work: The study reviews prior research on hybrid meeting challenges (e.g., technological barriers, audio delays) and types of backchannel communication (e.g., voice communication, text messaging), highlighting a research gap in integrating backchannel communication with hybrid meeting contexts.

Solution

• Proposed Method: The authors developed a voice communication system called WhisperChannel, designed to promote engagement and equity in hybrid meetings through a low-cost, inclusive backchannel communication approach.

• Innovations:

  1. Introduced a "walkie-talkie-like" mechanism that enables instant two-way voice communication with a single click, reducing usage barriers.
  2. Incorporated a spatialized user interface that graphically represents the meeting room structure and backchannel dynamics, enhancing remote participants' situational awareness.
  3. Designed a voice communication feature that mimics real whispering, allowing participants to discreetly exchange information without significantly interrupting the ongoing foreground meeting.

• Implementation Steps and Key Technologies:

  • Design Features:
    • Layout Overview: Participants are visually represented in the system, merging the layouts of remote and on-site users in a virtual space.
    • One-click Communication: Users can initiate voice backchannel communication by selecting and clicking on another participant's avatar.
    • Backchannel Dynamics: Displays which participants are currently engaged in backchannel communication, increasing transparency in the meeting environment.
  • System Architecture:
    • WhisperChannel is built using web technologies, supporting operation on smartphones, tablets, and laptops.
    • Utilizes WebRTC for real-time audio signal transmission.

Research Outcomes

• Specific Results:

  1. WhisperChannel significantly improved inclusivity for remote participants, enabling them to engage more effectively in "side" discussions during meetings.
  2. For on-site participants positioned far from others, the system reduced the sense of physical isolation.
  3. Voice-based backchannel communication proved to be more real-time and less burdensome compared to text-based communication.

• Advantages Compared to Existing Solutions:

  1. The communication method in WhisperChannel closely resembles real whispering, allowing users to naturally convey information compared to traditional text-based tools.
  2. Synchronous, two-way voice communication addresses the lack of immediate feedback often experienced by remote participants in meetings.

• Experiments and Evaluation:

  1. User studies involved three groups, each using WhisperChannel in two simulated hybrid meetings. Results showed enhanced engagement for both remote and on-site participants.
  2. Focus group feedback highlighted the system's advantages in reducing communication costs but also pointed out technical limitations (e.g., network delays and hardware imperfections) and challenges in social acceptance.

• Limitations and Future Directions:

  1. Limitations:
     • Hardware Constraints: Current headphone hardware quality and microphone performance are suboptimal, negatively impacting user experience.
     • Short-term Experiments: Two-hour user testing sessions cannot fully simulate long-term usage dynamics or encompass diverse hybrid meeting scenarios.
  2. Future Directions:
     • Technical Improvements: Enhance device compatibility and optimize audio transmission latency.
     • Long-term Studies: Design extended experiments in real-world meeting environments to validate the system's potential.
     • Multimodal Expansion: Explore non-voice communication methods (e.g., gestures or real-time text conversion) to further reduce communication costs.

Through this study, the authors successfully proposed a novel tool that demonstrates innovative methods to enhance inclusivity and reduce backchannel communication costs in hybrid meetings, while also inspiring rich potential for future research.