Schizophrenia Q 18
The etiology of schizophrenia is best described by:
A. Genetics due to a faulty dopamine receptor.
B. Environmental factors and poor parenting.
C. Structural and neurobiological factors.
D. A combination of biological, psychological, and environmental factors.
Correct Answer: D. A combination of biological, psychological, and environmental factors.
A reliable genetic marker hasn’t been determined for schizophrenia. However, studies of twins and adopted siblings have strongly implicated a genetic predisposition. Since the mid-19th century, excessive dopamine activity in the brain has also been suggested as a causal factor. Communication and the family system have been studied as contributing factors in the development of schizophrenia. Therefore, a combination of biological, psychological, and environmental factors are thought to cause schizophrenia.
Option A: Several studies postulate that the development of schizophrenia results from abnormalities in multiple neurotransmitters, such as dopaminergic, serotonergic, and alpha-adrenergic hyperactivity or glutaminergic and GABA hypoactivity. Genetics also play a fundamental role – there is a 46% concordance rate in monozygotic twins and a 40% risk of developing schizophrenia if both parents are affected. The gene neuregulin (NGR1) which is involved in glutamate signaling and brain development has been implicated, alongside dysbindin (DTNBP1) which helps glutamate release, and catecholamine O-methyltransferase (COMT) polymorphism, which regulates dopamine function.
Option B: A viral infection, extensive exposure to toxins like marijuana, or highly stressful situations may trigger schizophrenia in people who have inherited a tendency to develop the disorder. It tends to surface when the body is undergoing hormonal and physical changes, such as during the teen and young adult years.
Option C: Twin studies suggest that at least some of these changes may result from other than genetic factors. Functional disturbances of the brain have also been connected with frontal and temporal structures in some schizophrenic patients. Of the single neurotransmitter substances, dopamine and serotonin appear to represent some of the central restitutive mechanisms whose function is to maintain mental stability; the understanding of their interplay with other neurotransmitters such as noradrenaline, acetylcholine, GABA, and glutamate, should provide a more integrated view of both normal and disturbed brain function.