Optimal latency for video calls

Index date: 2022-11-01

Last modified: 2023-07-23

I was on the phone to my partner the other day while he was walking back from church and I realised that the latency on a mobile phone call is quite high – maybe about a second – but we have no problem with accidentally starting to talk over each other. I found this very strange because I’ve been on video calls with what I assume is much lower latency, and it seems quite common for people so start talking at the same time, particularly as a group.

This makes me wonder if the additional visual information included in a video call changes the timing behaviour of participants. I also wonder if there if ‘simultaneous start-ups’ have a non-linear response to latency: is there an optimal, non-zero amount of latency in a video call which reduces the rate of simultaneous start-ups?

I had a quick look for scholarly articles on this but so far the closest thing I’ve found is this article which discusses the issue, but I haven’t found anyone trying to directly measure the effect of latency on this phenomenon.

Malabarba, Taiane, Anna C. Oliveira Mendes, and Joseane de Souza. ‘Multimodal Resolution of Overlapping Talk in Video-Mediated L2 Instruction’. Languages 7, no. 2 (June 2022): 154. https://doi.org/10.3390/languages7020154.