Hello,
Many things may cause this like large data transfers, CPU spikes (whatever the cause). Hard to tell from just a screen capture, but I wouldn't worry for a glitch like that.
Thing is to know your network and what is normal for you. This is called baselining. If you expect (through regular verification) a response time of X mSec and one day you see a
sustained delay of Y mSec, then you start troubleshooting.
Make sure that you have an up to date network diagram. It'll help you a lot! Even for smaller networks.
P.S. The OCD in me says "write your units correctly". There's a huge difference between Msec (10 power of 6) and msec (10 power of -3)
Cheers,