Brian has been diagnosed with bipolar disorder. One symptom he experiences during both his manic and depressive episodes is disturbance to his sleep. What links mania, depression, and sleep?

Serotonin levels link mania, depression and sleep.

Explanation:

Individual diagnosed with bipolar disorder display lowered levels of serotonin during both phases. Meanwhile sleep disturbance is more common during the manic phase.

As one of the fundamental neurotransmitters, serotonin is responsible for a wide range of psychological and physiological processes, including sleep. That is why a group of antidepressants called SSRIs (serotonin reuptake inhibitors) can improve sleep significantly. Several studies found that serotonergic transmission has a major role in sleep deprivation management.

Behavioral factors also can contribute to sleep problems among individuals with bipolar disorder. For example, they might consume stimulants that affects sleep by impeding production of melatonin.

Behavioral factors also can contribute to sleep problems among individuals with bipolar disorder. For example, they might consume stimulants that affects sleep by impeding production of melatonin.