Kinda like WFH, this varies a lot from people to people. Well, I don't know about the damage part, but definitely, for some of us, intense multitasking leads to cognitive decline (it was reversed for me hence why I said "I don't know about the damage part")

I spent a few years working on a Support team, at least a couple of those years managing that team, and part of my job involved being interruptible with a very short response time, on several different channels (I mean email, IM, phone, etc.)

I liked that job as I met great people and learned a lot, but the moment I was able to shift into a more focused position (within the same company) I felt a great relief, an improvement in my quality of life, and a recovery of my cognitive skills. At that same company, I had (had because I no longer work there, we're still friends of course) a great friend, someone whom I know since we were 16 (We're 44 now), and he's the exact opposite and took the opposite path: He started off doing dev work, focusing on just a few tasks at a time, but it didn't work for him (even though he was amazing at his job) and ended up loving working as a support engineer. He thrives in an environment where he gets interrupted multiple times per hour (!!) during his work day, with no impact at all on his cognitive skills. In fact, not only is he a great problem solver, while dealing with multiple problems in parallel (and the interruptions include having to jump on a screen-sharing session without warning, something I can't tell you how much I feared and despised when I had to do that job!), he can tell you by heart the numbers of all the tickets he's working on, including their description and context. And I don't mean while working, I mean over beers at a meetup ...

The one thing we both agree on is that we love WFH and would never, ever go back to an office (he's been WFH pretty much all his life, while I've been doing that for 15 years now). And just as that is the case for us, I also know personally people who don't like WFH and need to go to an office every day in order to be productive and to feel a human connection with their coworkers.

Is your friend in support engineering truly being interrupted however? I think it has a lot to do with stack depth. Working on task A, then being interrupted to work on task B only to be interrupted again to work on task C is the source of brain damage - particularly for those who care about being productive.

"The cost of an interruption is not just the time it takes, but that it breaks the time on either side in half. You probably only have to interrupt someone a couple times a day before they're unable to work on hard problems at all." -- PG

I (of course) think of it like multi-tasking in a computer. The machine needs to capture the context (stack and registers) associated with one task in order to switch to another. However, for a human this context can be enormous. Depending on the task, it is possible that one will never get back to the state of understanding that they had at an earlier point if working on a particularly complex thing - just the right combination of caffeine, sleep, motivation (more accurately gumption if you have read ZAMM), etc.

The ZAMM reference is spot on to me. The moment I used to get an interruption (typically an incoming call, but not only that), what happened to me was just what Pirsig describe of the gumption leaving you like air from a baloon, psssst.

I eventually got into 'the zone' and I was actually quite good at figuring out problems with little context, but my gumption was gone nevertheless, and I was useless for whatever thing I was working on before the interruption for mostly the rest of the day.

Yes, I think it is the most important software engineering book by far.

Yeah, he's working in an intense context-switching environment. Also, since he's a very senior team member he gets interrupted frequently for escalations or just for short help requests.

The context-switching is what killed me when I did that, and he actually does enjoy it, as crazy as it sounds!

Well, I guess it is a good thing that there is more than one type of brain out there!

information overload is real for sure, but if you can strike that balance between being educated/informed, and also disconnecting/meditating/etc., then it's net-positive.

prioritization and setting time limits/routines/schedules is key here imo.