Clinical practice at the interface between psychiatry and neurology is often called neuropsychiatry. Neuropsychiatry is based on: (a) a systematic, clinical approach to patient assessment based on the known psychological and behavioural correlates of damage to different parts of the brain; and (b) a clinical assessment not only of this impairment but also of the psychological and social factors associated with the subsequent disability and handicap.
Mental state examination
The mental state examination in neuropsychiatry needs to be adapted as the patients’ neurological condition often directly affects the expression of emotion. A detailed discussion of the effects of specific brain lesions on emotion and behaviour can be found in Bogousslavsky ' Cummings (2000).
Aphasia leads to the abolition of all linguistic faculties, and recording of mood and emotion is speculative. Assessment can be attempted with visual scales, but given the loss of inner monologue their interpretation should be approached with caution. Dysphasias are often associated with frustration and irritability.
Anosognosia refers to partial or complete unawareness of a deficit. It may coexist with depression. Anosognosia for hemiplegia is perhaps most described, but it can affect any function.
Affective dysprosody is the impairment of the production and comprehension of language components which allow the communication of inner emotional states in speech such as stresses, pauses, cadences, accent, melody and intonation. Its presence is not associated with an actual deficit in the ability to experience emotions, only in the ability to communicate or recognise them.
Apathy manifests as reduced spontaneous actions or speech, and delayed, short, slow or absent responses. Apathy is frequently associated with hypophonia, perseverations, grasp reflex and compulsive manipulations.
Emotional lability or emotionalism with an increase in laughing or crying with little or no warning signals is frequent after stroke and after traumatic brain injury. There is an association with depression but the two can exist independently (House et al, 1989).