Final answer:
A low level of neurotransmitters in the brain can cause various physical and mental disorders, impacting functions such as movement and mood. Low serotonin levels are associated with depression, and dopamine-related deficiencies can result in movement disorders like Parkinson's. Medications can alter neurotransmitter levels to treat these conditions.
Step-by-step explanation:
If a person's brain has a low level of neurotransmitters, it has several implications. Neurotransmitters are chemicals that transmit signals from one neuron to another across synapses. They play a critical role in the proper functioning of our central nervous system (CNS), which includes the brain and spinal cord. An abnormally low level of a neurotransmitter can affect brain regions that control specific functions. For example, low levels of dopamine can negatively impact the part of the brain responsible for movement, leading to disorders like Parkinson's Disease.
Low levels of another neurotransmitter, serotonin, are often associated with depression. Antidepressants work by increasing serotonin levels, helping to control symptoms and improve the quality of life for those with depression. Furthermore, neurotransmitter imbalances are thought to play roles in anxiety, bipolar disorder, schizophrenia, and ADHD. A lack of neurotransmitters means that neurons would not be able to receive input properly, leading to physical and mental disorders.
It's also important to note that neurotransmitter levels can be affected by psychoactive drugs, which can either increase or decrease the activity of these crucial chemicals in the brain. Antagonists reduce the activity by blocking neurotransmitter binding, whereas agonists increase activity in various ways, including mimicking the neurotransmitter's action.