A "blank" or expressionless face that does not change with the topic of conversation.

Poor or nonexistent eye engagement with others.

Speech that is monotone or lacks normal inflection (prosody).

A marked reduction in body language and expressive hand movements.

Flattening of Emotions: A Clinical and Neuropsychological Overview

Affective flattening is identified through subtle behavioral cues observed by clinicians, including:

, clinically referred to as affective flattening or flat affect , is a disorder characterized by a gross lack of emotional response to a given situation. It is primarily recognized as a reduction in the outward expression of emotion, regardless of whether the internal experience of the emotion is diminished. This condition is most commonly associated with schizophrenia , where it is classified as a "negative symptom," but it also appears in depression, post-traumatic stress disorder (PTSD), and certain neurological conditions. Definition and Clinical Presentation