Constant interruptions and left brain - right brain thing

I've read several times lately on the web and in books about how coding
requires left brain and when interrupted it knocks you into right brain
mode. It then takes some time (1-2 hours) to get into proper left brain mode
again. I've felt that way for a long time (not sure about 2 hours but after
a minor interruption (even if it's only for 1 minute, or a phone ringing) it
knocks me straight out of concentration and it takes me at least 5 minutes
before I can start to code again (much longer to reach full speed). Plus of
course all these interruptions when halfway through writing a line of code
or SQL statement all increase the chances of bugs particularly if when I
come back the line or function looks at first glance to be finished when it
isn't. I may even have totally lost my position in the code (or even forgot
what program I was editing) as a result of being called into a meeting
suddenly on my way back to the office from some other department and the
meeting in question involved an RDP session into my PC to view something on
there (which happens to rearrange all the window sizes, which monitor they
appear on, etc).

Anyhow, just wondered what the level of interruptions is like elsewhere,
really. Generally, the longest block I have in a typical day without an
interruption is about 40 minutes. The majority of these come from either the
IT manager or one of the other developers (I am one of 3 in total at my
company). Requests from the IT manager are mostly minor alterations
requested for programs (change of some text somewhere on the user interface,
change of wording in an automated e-mail, etc) and from one of the other
developers requests for help (sometimes database related but mostly obvious
problems that I'm sure he could fix himself if he spent another 2 minutes on
it). The other developer does not require assistance anywhere near as much.

I've asked them both to e-mail me these things instead of just standing next
to me and talking but it never seems to happen (and in the IT managers case
he's usually too busy running around the different departments to get to a
PC and send an email anyway). E-mail doesn't really bother me at all as
there's several different points throughout the day when I'm between tasks
and can read/respond without losing track of the particular feature /
function I'm working on.

So, what's typical elsewhere, and any advice on dealing with the problem?
I've also posted a typical work day in a separate post here.



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