Kamma and (psychiatric) delusions / madness if I am mad and my action would not have been performed if not for loss of reality (i.e. psychosis) will I still bear its -ve fruit?

As a Buddhist or otherwise.

Please answer sensitively :)
"The Pali term Karma literally means action or doing. Any kind of intentional action whether mental, verbal, or physical, is regarded as Karma"         

You have to look at the action (good or bad) and the  consequence( Kamma &amp; vipaka). whether one has a sound mind or unsound mind doesn't matter, without intention there is no action.

Even a person suffering from psychosis uses his mind to do things,  so without thoughts nothing good or bad  happens( the thoughts may be abnormal,incomplete,unclear or confusing)  ,but a person with psychosis may not feel the consequences like a normal person ,so the magnitude of suffering may differ for the same actions committed by different people.