I love the fact that three years ago no one would have any idea what the title of this post meant, and now pretty much everyone does. It’s a testament to the rapid pace of cultural change driven by digital technology. Over the last two years of the pandemic many people have become familiar with the app Zoom, which is a video conferencing app that was in the right place at the right time with the right features. There are, of course, other apps but Zoom clearly dominated the market.

Regardless of the app being used, video conferencing for many displaced school, lectures, work meetings, and even social gatherings. For those not already familiar with such technology it was a rapid education (Dude, you’re on mute!). Twenty-five percent of my patient visits are now over zoom, so I get to see the full spectrum of comfort with the technology, although overall it is definitely improving.

Many people, including Julie Boland who is a professor of psychology and linguistics, noticed that video conferencing can sometimes be more fatiguing than in person conversations. So she decided to research why that might be. Her initial hunch is that it might have something to do with the short delay in transmission times throwing off the natural rhythms of human conversation. Previous research had identified four contributors to Zoom fatigue – intense and slightly misaligned eye contact, being on camera, limited body movement, and lack of nonverbal communication.

As we learn to optimize the use of video conferences some of these factors are easily dealt with. For example, you can simply turn off your camera when you are not the speaker. This saves some digital throughput and energy as well, and means you don’t have to be on-camera the whole time, even when just listening. The misaligned eye-contact can be mitigated by placing the video window as close to your camera as possible, and adjusting the camera so that you are well-framed for others. Also, pure audio conversations can be just as good, and the video does not always add anything. I have been doing this for over 16 years, with five people recording a long podcast every week using just audio. You adapt.

But there is another element that, even after 16 years of doing this at least once a week, still remains an issue. There is a different rhythm to a conversation over a conferencing app than in person. Again, you can develop tricks to adapt to the change, but it is still not as good an experience as in-person conferencing. From my experience there are two main reasons for this. The first, as listed above, is lack of non-verbal cues. When physically together we can use non-verbal cues in order to navigate who is going to speak next. It’s still not perfect, but it is much smoother than a remote conference. With five people talking minus any visual cues, we have to rely on a shared etiquette to coordinate who is going to speak. It’s still a mess, which is fixed in post production for the podcast.

The second factor is the transmission delay. This is much better now than it was 16 years ago when we started, but still crops up if someone has a bad connection. At worst the delay is just enough that people tend to talk right over each other. You pause briefly to see if the other person is going to speak, then when you start speaking they do also. This can happen several times in a row, until you just have to agree on who is going to speak. At worst, it can be maddening. With good connection times this does not happen, but even still you have to change the rhythm of normal conversation a little bit. You need to be much more aware of the other speakers, pause a bit longer before jumping in, or just speak over someone else who then has to wait their turn to break in. Sometimes you just need a referee to resolve a conversational log-jam.

Boland apparently noticed these phenomena as well, and so hypothesized that one contributor to Zoom fatigue was the increased cognitive load created by this delay in transmission time messing with the normal rhythm of conversation. She ran two experiments. In the first she found that answers to yes/no questions took three times as long when asked over Zoom than when played on one’s own computer (so minus the transmission delay). The second focused on transition times between two speakers, the delay between one speaker ending and the other beginning. In person conversations have an average transition time of 135 milliseconds (in line with prior research). Zoom transitions, however, took 487 milliseconds. That is still a brief delay, but more than triple normal. She further found that people speak longer during Zoom conversations, meaning there are fewer transitions.

So far this just supports experimentally what many users have observed anecdotally. The question Boland raised from this is whether or not there is a neurological basis for the increased delay. Often, a delay like this represents increased mental work being done, due to increased cognitive load or what researchers call “interference” due to multitasking or distractions. Prior research shows that some brainwave patterns tend to sync up with the rhythm of conversational speech. If the average length of one syllable is 100 ms, then certain brainwave rhythms also are paced at 100 ms (with about a 20% tolerance on either end). The suspicion is that this has something to do with how our brains evolved to have efficient conversations. Our brains are really good at conversations – we can listen to what someone is saying, process it, think of a response, and then time our response to a host of verbal and non-verbal cues. This does not always work flawlessly, and some people are better than others, but generally speaking we effortless pull off a feat of linguistic multitasking during a typical conversation.

The hypothesis, therefore, is that throwing off this rhythm simply messes with our evolved algorithms for managing conversations. This increases our cognitive load, and contributes to Zoom fatigue. There is no research to prove this hypothesis, but it is plausible and at least compatible with existing research. Further studies can clarify this by testing the effects of changing variables, such as delay time.

We may be in a short window for this phenomenon as well. Technology may fix it for us, and digital remote conferences better replicate an in-person experience with shorter transmission delays. They are already much better than 10 or 20 years ago, and perhaps in another decade the problem will fade completely. Meanwhile we each need to find ways to adapt to optimize the Zoom experience and minimize fatigue.