flat affect

(medicine) Lack of emotion, or of apparent emotion.

Japanese Meaning

無表情 / 感情の乏しさ / 扁平な感情

The psychiatrist noted the patient's flat affect during the evaluation.

精神科医は診察の際、患者の感情表現の欠如に気づいた。

Sense（1）

(medicine) Lack of emotion, or of apparent emotion.

After the crash he presented a flat affect, a symptom of PTSD.

flat affects

（ plural ）