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Seasonal changes in bipolar disorder
In some people with bipolar disorder, spring and summer can bring on symptoms of mania or a less intense form of mania (hypomania). This is known as reverse seasonal affective disorder. Signs and symptoms of reverse seasonal affective disorder include:

• Persistently elevated mood
• Hyperactivity
• Agitation
• Unbridled enthusiasm out of proportion to the situation
• Rapid thoughts and speech