Mood-incongruent behaviors are not consistent with a patient's current mindset or are at conflict with current situational factors.
For example, laughing at a funeral would be considered mood-incongruent. This is the opposing concept of mood-congruent behavior which is when expressed actions and emotions are consistent with how the individual actually feels (such as smiling when happy and frowning when sad.)
Mood-incongruent can also be used to describe certain delusions. A mood-incongruent delusion is not consistent with the mental state of the individual experiencing the delusion.
An example would be a depressed person who believes that their thoughts are being transmitted to their brain by another person. This is a bizarre and manic delusion which is not congruent with someone who is in a depressed state. The opposing concept of this is a mood-congruent delusion which is a delusion that is consistent with the individual's current mental state. For example, a mood-congruent delusion of a depressed person may be that everyone on the planet hates them and wishes they were dead. This delusion is consistent with depression.