Can you hold concentration while sleeping?

Yes you can maintain concentration during a short rest, because being at short rest is not among things that breaks concentration (taking damage or being incapacitated). I think this is not valid when you go to sleep (long rest).

Can you regain spell slots during a short rest?

You regain all expended Spell Slots when you finish a short or Long Rest. For example, when you are 5th level, you have two 3rd-level Spell Slots.

Can you maintain concentration while stunned?

The only condition that stops concentration is Incapacitated. So, Fear would not break concentration, whereas Hideous Laughter would. Edit- other conditions such as paralyzed, petrified, stunned, and unconscious also include incapacitated in their effects, so they would also break concentration.

Do you lose concentration when unconscious?

Does the unconscious condition break concentration? Yes, the unconscious condition specifically says an unconscious creature is incapacitated. Becoming incapacitated will end concentration.

Can You maintain concentration through a long rest?

So, you probably can’t maintain concentration through a long rest, unless you’re an elf! (Because they don’t sleep.) A long rest is a period of extended downtime, about 8 hours long, during which you sleep or perform light activity: reading, talking, eating, or standing watch for no more than 2 hours of the rest period.

What do you do during a short rest?

[A] short rest is a period of downtime, at least 1 hour long, during which a character does nothing more strenuous than eating, drinking, reading, and tending to wounds.

What to do if you are unable to concentrate?

Lifestyle changes that affect your concentration include: Being unable to concentrate is also a side effect of some medications. Read the insert carefully. Contact your doctor or pharmacist to determine if your medications may be affecting your concentration.