What is a common psychological symptom in schizophrenia besides hallucinations?

In schizophrenia, delusions are a common psychological symptom alongside hallucinations. Delusions are firmly held false beliefs that are resistant to reason or contrary evidence. Individuals experiencing schizophrenia may believe they are under constant surveillance, that they possess extraordinary abilities, or that they are the subject of a conspiracy. These beliefs can significantly impact their behavior and interactions with others, often leading to distress and impaired functioning.

In contrast, the other options do not reflect typical symptoms of schizophrenia. Increased self-confidence, motivational clarity, and a preference for solitude are not recognized as common features of the disorder. While some individuals with schizophrenia may struggle with social interactions and might prefer solitude, this is more a result of their symptoms and the impact of their illness on social functioning rather than a defining characteristic of the disorder itself. Thus, delusions stand out as a prominent psychological symptom relevant to the condition.