Negative symptoms are the absence or reduction of normal functions or behaviours typically present in healthy individuals. They are often discussed in the context of mental health disorders, particularly schizophrenia. These symptoms can significantly impair daily functioning and can be challenging to treat. 

Examples of negative symptoms are: 

• Reduced ability to experience pleasure from once enjoyable activities. 
• Lack of motivation or initiative to begin or sustain activities. 
• Limited emotional expressions, such as reduced facial expressions or voice tone. 
• Reduced speech output or thought production, leading to very brief and sometimes monotonous conversations. 
• Avoiding social interactions or relationships due to lack of interest or pleasure in socializing.