Verified by 
Many of us are spending hours in video meetings and finding them a lot more tiring than face-to-face gatherings. That’s because meeting online increases cognitive load and eats up a lot of our mental capacity.
When face-to-face, we effortlessly process a slew of non-verbal signals: facial expression, gestures, posture, the distance between speakers, and the tone and rhythm of a voice. We can do this automatically and still follow what the speaker is saying, but at an energy cost. We read body language to make emotional judgments as to whether someone is credible or not. Are they fidgeting, guarded, or looking away rather than making eye contact? Weighing these is easy in person, but video chats force us to work harder to process these nonverbal cues, and this consumes a lot of physical energy.
The brain’s fixed bandwidth of attention
Compared to electronics, the human brain operates at ridiculously slow speeds of about 120 bits (~15 bytes) per second [1]. Listening to one person takes about 60 bits per second of brainpower, half our allotted bandwidth. Trying to follow two people speaking at once is nigh impossible for the same reason that multitaskers fare poorly: attempting to handle two or more simultaneous tasks consciously maxes out our cognitive bandwidth.
That bandwidth is fixed biologically, and no amount of diet, exercise, Sudoku puzzles, or yoga can increase what we have to work with. All we can do is direct and focus our attention thoughtfully.
Most Zoom complaints concern the video—the bothersome lack of eye contact, the strain of focusing on a dozen or more participants, the worry about needing to seem interested. All this takes added emotional effort, and having to focus on words without the nonverbal cues that are typical in a personal meeting becomes exhausting.
Why Zoom and Skype fatigue us
For a long time, a small number of technical folks have known that Skype and Facetime are unsatisfying compared to meeting in the flesh because the camera is positioned in the wrong place. Now. millions experience the uncanny self-consciousness about how one looks. Webcams that peer up at the user add 10 pounds under the jawline, causing the dreaded double-chin online.
And yet it’s the audio that makes Zoom encounters draining. No matter what language is spoken, all cultures have well-organized rules for taking turns. This assures no overlap but no long pauses in conversation either. Online meetings disrupt that because separate sound and video streams are chopped into tiny “packets” and sent via different pathways to the recipient’s end where they are reassembled. This so-called packet switching technology is extremely robust. The defense agency that pioneered the Internet in the 1960s made it so that enemies couldn’t knock it out with a single hit. The system could easily reroute itself through undamaged portions and deliver the full message intact.
The cause of Zoom glitches
This chopping up is a problem when it comes to online meetings, however. When some packets arrive late the software must decide whether to wait for reassembly—leading to a delay—or stitch together whatever packets are available, giving rise to glitches.
Video calling platforms have opted for audio that arrives quickly but it is low-quality. A platform aims for a lag of just 150 milliseconds. Yet even that is too much under the no-overlap/no-gap convention that people are used to. A round-trip signal can be delayed up to 300 milliseconds before one gets a reply, a too-long pause that makes speakers seem less convincing and trustworthy.
A bigger problem than delays are interruptions when speakers talk over one another. Repeatedly having to sort out these clashes over who goes first is tiresome and draining. So is having coworkers who are hard to understand because of an accent; having to repeat themselves likewise makes them come across as less credible.
No breakroom chat
The simple act of walking is well-documented to improve problem solving and creativity. At the office, we can congregate in the break room or around the water cooler. We can poke our head in down the hall. The physical location where we meet with co-workers matters, too. Every location carries certain implicit meanings that color our actions and way of thinking. At home, everything merges into one amorphous mass. And we can’t pace the room during Zoom calls, either. Instead, we may feel stuck and confined.
Ways to reduce Zoom fatigue
Zoom, Skype, and FaceTime seem here to stay. The first step is to ask whether a meeting really needs to happen. Oftentimes, documents shared across Acrobat, Google Docs, or Office will obviate the need for on-camera conversation. Talking by phone is still quick and efficient, too. It also takes less effort than Skype or Zoom. On the phone, we can concentrate on only one voice. We can pace around during a phone call, too, which helps our thinking.
Please email comments via he website listed below, or to join Dr. Cytowic's low-frequency newsletter or ask for a free copy of "Your Brain on Screens."
References
[note 1] My Verizon fiber optic connection shoots data into my home at 8,589,934,592 bits per second, about 71,600,000 times the rate my gray matter can handle. At most, a nerve cell can discharge electrical spikes 1,000 times per second down one nerve axon to another cell. The fastest a signal can cross a synaptic gap is about 1 millisecond. Considering both numbers, the brain can therefore carry out a maximum of 1,000 operations per second, 10 million times slower than an old laptop.
