Final answer:
The correct answer is b) Cortisol. Elevated levels of the stress hormone cortisol can aggravate the symptoms of schizophrenia, likely due to the extended physiological stress response and hormonal imbalances it causes.
Step-by-step explanation:
People with schizophrenia who have elevated levels of the stress hormone cortisol may experience more severe symptoms of their illness. Stress hormones like cortisol are released during the body's response to stress and can influence a variety of physiological processes. In regards to schizophrenia, extended or chronic release of cortisol can contribute to the worsening of symptoms. In individuals with major depressive disorder (MDD), for instance, elevated cortisol levels have been commonly observed and are associated with stress-system dysfunction.
Furthermore, chronic stress resulting in prolonged exposure to cortisol has been linked to harmful effects including weakened immune response and heightened potential for illnesses. Since stress is able to exacerbate schizophrenia symptoms, managing stress levels through therapy, medication, and lifestyle interventions can be an essential part of treatment, alongside managing the fundamental neurotransmitter imbalances, particularly those involving dopamine.
Therefore, the correct option in the original question is b) Cortisol, given that abnormally high levels of this stress hormone may intensify the manifestations of schizophrenia.