There is an increased risk depression and anxiety will develop after a head injury or neurological disease. Depression and anxiety must be acknowledged and treated. Antidepressant medication and psychological treatment can provide good help with depression and anxiety. Low-dose anti-depressant medications can also help with emotional lability/tearfulness and irritability, but do not help for brain fatigue. 

It is important to distinguish brain fatigue and depression. Both symptoms can occur separately but also simultaneously. There are several symptoms that overlap but the core symptoms for the two conditions are different. In brain fatigue there is a clear fatigue that is related to mental activity and often activities exceeds what is possible to do. Fatigue often has a daily variation, recovery is long and rest helps. In depression there is a continuous low mood or sadness and reduced interest in things. Fatigue is more constant.