Hallucinations are sensory experiences that occur in the absence of any external stimuli, commonly involving hearing voices or seeing things that others do not. Delusions are false beliefs that are not based in reality and may involve ideas of persecution, grandiosity, or paranoia. Disorganized thinking can manifest as difficulty organizing thoughts, speaking coherently, or maintaining a logical flow of ideas. Disorganized or abnormal motor behavior may include unpredictable or inappropriate movements. Negative symptoms refer to a reduction or absence of normal emotions or behaviors, such as diminished motivation, social withdrawal, or reduced emotional expressiveness.