A flat affect is the loss or lack of emotional responses to a situation or event that would typically elicit emotion. People with flat affect may appear to be completely unemotional or apathetic. Other associated symptoms include speaking in a monotone voice and a reduction in facial expressions. A flat affect is sometimes referred to as a blunted affect, although a blunted affect often refers to a reduction in emotions that is not as severe as that seen with flat affect. Flat affect can occur in association with schizophrenia or in some types of depression.

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