The _______________ states that schizophrenia may be caused by an excess of certain neurotransmitters in the brain.

Neurotransmitters are the body's chemical messengers. They play an indispensable role in transmitting signals in the brain and throughout the nervous system. Every thought, emotion, and action depends on these tiny molecules. For example, when you feel happy, your brain might be releasing a neurotransmitter called dopamine. On the other hand, when you're stressed, another one called cortisol is at play.

The proper balance of neurotransmitters is critical for maintaining mental health. If their levels are too high or too low, it can lead to various issues. For instance, the 'fight or flight' response is a result of neurotransmitters preparing your body to react to a perceived threat—but if there's an imbalance, this response can be activated at inappropriate times, leading to anxiety or other disorders.

Schizophrenia is a chronic and severe mental health disorder that affects how a person thinks, feels, and behaves. It's often characterized by hallucinations, delusions, and disordered thinking and behavior, which can impede daily functioning.

The development of schizophrenia is thought to involve a combination of genetic, physical, psychological, and environmental factors. Treatment often includes antipsychotic medications and psychosocial therapies. Since the discovery of antipsychotic drugs, which ameliorate the symptoms of schizophrenia by affecting the neurotransmitters in the brain, scientists have been trying to unravel the exact mechanisms at play in this complex disease.

The dopamine system plays a major role in reward, motivation, memory, and attention. It is also associated with pleasure and motor function. This system involves pathways in the brain where dopamine travels and binds to receptors to transmit signals.

Abnormalities in the dopamine system can lead to neurological and psychiatric conditions. In Parkinson's disease, for instance, the death of dopamine-producing cells causes motor symptoms. Similarly, an imbalance in dopamine levels is implicated in mental health conditions, including schizophrenia, suggesting that the dopamine system's regulation is crucial for normal brain function.

D2 receptors are a specific type of dopamine receptor found in the brain. There are several types of dopamine receptors, but D2 receptors are especially noteworthy in the study of schizophrenia. Antipsychotic drugs, used to treat schizophrenia, often work by blocking these receptors.

Research has shown that individuals with schizophrenia may have an increased number of D2 receptors, or the receptors might be overly sensitive, leading to a heightened response to dopamine. This maintains the dopamine hypothesis of schizophrenia, which suggests that psychosis could result from this overactivity in the dopamine system involving D2 receptors.