Affect is described by labelling the apparent emotion conveyed by the person’s nonverbal behavior (anxious, sad etc.), and also by using the parameters of appropriateness, intensity, range, reactivity and mobility.
Affect may be described as appropriate or inappropriate to the current situation, and as congruent or incongruent with their thought content. For example, someone who shows a bland affect when describing a very distressing experience would be described as showing incongruent affect, which might suggest schizophrenia.
The intensity of the affect may be described as normal, blunted affect, exaggerated, flat, heightened or overly dramatic.
A flat or blunted affect is associated with schizophrenia, depression or post-traumatic stress disorder; heightened affect might suggest mania, and an overly dramatic or exaggerated affect might suggest certain personality disorders.
Mobility refers to the extent to which affect changes during the interview: the affect may be described as mobile, constricted, fixed, immobile or labile.
The person may show a full range of affect, in other words a wide range of emotional expression during the assessment, or may be described as having restricted affect.
The affect may also be described as reactive, in other words changing flexibly and appropriately with the flow of conversation, or as unreactive.