I guess that would depend on the colour. If you paint four walls bright red, don't expect it to bring peace and harmony. In fact I suspect that bright colours need to be used to be used pretty judicially. Okay for a feature wall, maybe. But pastels of just about any shade seem to be more conducive to a home one can relax in. Also, they make the room seem bigger.
A hint - something I learned long ago. Take a bright colour, say, red or blue. A little piece about as big as a coin will do. Place it on a white background. Stare at the colour until you find you can't really comfortably look at it any longer. Then whip it away and look at the same spot where that coloured piece was. After a second or so it's exact complimentary colour will appear. For example, if you use blue, the compensatory colour will be yellow.
Now, if you paint adjacent walls with each colour (meeting at the corners of the room) you'll find it seems to provide a cheerful and harmonious room set.
Try it. But mix in plenty of white paint with the colours you eventually choose. Don't have them too dark or too bright. I think you'll find this an answer to what you seek re colour.