Final answer:
Mood disorders are correlated with low levels of serotonin and norepinephrine in the brain, which are integral to mood regulation. Antidepressant medications work by increasing these neurotransmitter levels to treat depression.
Step-by-step explanation:
Mood disorders are often correlated with low levels of two key neurotransmitters in the brain, which are serotonin and norepinephrine. These neurotransmitters play critical roles in regulating mood, attention, and emotion. Decreased levels of serotonin and norepinephrine have been specifically associated with the symptoms of depression.
Medications known as antidepressants aim to increase the levels of these neurotransmitters, thereby alleviating depressive symptoms. This can involve blocking the reuptake of neurotransmitters so that they remain in the synapse longer or inhibiting the enzyme that degrades them, leading to increased levels within the brain.
There is also evidence to suggest that other neurotransmitters like dopamine may be involved in mood disorders, and that treatment efficacy could relate to changes in neurotransmitter dynamics over time rather than immediate increases in neurotransmitter levels.