Registered Practical Nurse (RPN) Practice Test

What does positron emission tomography (PET) scans suggest about brain metabolism in schizophrenia?

1. A general increase in brain metabolism

2. A general reduction in brain metabolism

3. No significant changes in brain metabolism

4. Localized brain hyperactivity

The correct answer is: A general reduction in brain metabolism

Positron emission tomography (PET) scans indicate a general reduction in brain metabolism in individuals with schizophrenia. This reflects the underlying pathophysiology of the disorder, which is often associated with impaired neural functioning and alterations in neurotransmitter systems, particularly those involving dopamine and glutamate. Research has shown that individuals with schizophrenia may exhibit decreased activity in several brain regions, including the prefrontal cortex and temporal lobes. These areas are critical for higher cognitive functions such as working memory, attention, and emotional regulation. A reduction in metabolic activity in these regions can contribute to some of the core symptoms of schizophrenia, such as cognitive deficits, negative symptoms, and impaired social functioning. In contrast, other choices describe scenarios that do not align with the findings generally reported in studies using PET imaging in this context. For example, a general increase in brain metabolism would suggest enhanced neural activity, which is inconsistent with the depressive and cognitive symptoms often observed in schizophrenia. No significant changes in brain metabolism would imply that the brain function is relatively unaffected, which does not reflect the typical neurobiological changes associated with the disorder. Localized brain hyperactivity is more commonly observed in specific areas related to certain symptoms, such as hallucinations or delusions, rather than representing an overall