Which term refers to the observable aspects of behavior that signal how one is feeling?

The term "affect" refers specifically to the observable aspects of behavior that indicate how a person is feeling at a given moment. This includes facial expressions, body language, and vocal tone, which can all reveal emotional states. Affect is often assessed in clinical settings because it provides immediate insight into a client’s emotional condition, making it a key concept in fields like psychology and music therapy.

In contrast, "emotion" pertains to the internal experience of feelings and encompasses a wider range of affective states. "Mood" refers to a more prolonged and pervasive emotional state that may not be observable in immediate behaviors but influences a person's overall emotional landscape. "Expression," while related, is a broader term that can refer to both verbal and non-verbal ways individuals convey their emotions or feelings, and does not specifically denote the observable behaviors alone. Thus, affect is the most accurate term in this context to describe the visible indicators of emotional state.