Dopamine and Learning
Dopamine is a catecholamine neurotransmitter present in a wide variety of animals, including both vertebrates and invertebrates. In the brain, this phenethylamine functions as a neurotransmitter, activating the five types of dopamine receptorsD1, D2, D3, D4, and D5and their variants. Dopamine is produced in several areas of the brain, including the substantia nigra and the ventral tegmental area. Dopamine is also a neurohormone released by the hypothalamus. Its main function as a hormone is to inhibit the release of prolactin from the anterior lobe of the pituitary.
Dopamine is available as an intravenous medication acting on the sympathetic nervous system, producing effects such as increased heart rate and blood pressure. However, because dopamine cannot cross the blood-brain barrier, dopamine given as a drug does not directly affect the central nervous system. To increase the amount of dopamine in the brains of patients with diseases such as Parkinsons disease and dopa-responsive dystonia, L-DOPA, which is the precursor of dopamine, can be given because it can cross the blood-brain barrier.
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2014人教新目标英语八下unit2《I’ll help to clean up the city parks》section b 2b课本听力素材（mp3）
2014人教新目标英语八下unit 7《What’s the highest mountain in the world》section a 3a课本听力素材（mp3）
2014人教新目标英语八下unit 6《An old man tried to move the mountains》课件3
2014人教新目标英语八下unit2《I’ll help to clean up the city parks》words单词听力朗读素材（mp3）
2014人教新目标英语八下unit 6《An old man tried to move the mountains》课件
2014人教新目标英语八下unit 7《What’s the highest mountain in the world》section b 1b课本听力素材（mp3）
2014人教新目标英语八下unit 8《Have you ever read treasure island yet》 period 4课件
2014人教新目标英语八下unit 7《What’s the highest mountain in the world》 period 3课件
2014人教新目标英语八下unit2《I’ll help to clean up the city parks》section b 1a-1e课件
2014人教新目标英语八下unit 8《Have you ever read treasure island yet》section a 1b课本听力素材（mp3）
2014人教新目标英语八下unit2《I’ll help to clean up the city parks》section a 2a课本听力素材（mp3）
2014人教新目标英语八下unit 8《Have you ever read treasure island yet》 period 1课件
2014人教新目标英语八下unit 7《What’s the highest mountain in the world》 period 4课件
2014人教新目标英语八下unit 7《What’s the highest mountain in the world》 period 2课件
2014人教新目标英语八下unit 7《What’s the highest mountain in the world》section a 2d课本听力素材（mp3）
2014人教新目标英语八下unit 7《What’s the highest mountain in the world》课件
2014人教新目标英语八下unit 9《Have you ever been to a museum》课件
2014人教新目标英语八下unit2《I’ll help to clean up the city parks》section a 2b课本听力素材（mp3）
2014人教新目标英语八下unit2《I’ll help to clean up the city parks》全单元课件
2014人教新目标英语八下unit 9《Have you ever been to a museum》专题复习课件
2014人教新目标英语八下unit 8《Have you ever read treasure island yet》section a 2a课本听力素材（mp3）
2014人教新目标英语八下unit 7《What’s the highest mountain in the world》section b 1c课本听力素材（mp3）
2014人教新目标英语八下unit 8《Have you ever read treasure island yet》 period 3课件
2014人教新目标英语八下unit2《I’ll help to clean up the city parks》section a 1a-2d课件
2014人教新目标英语八下unit 6《An old man tried to move the mountains》 section b 2b课本听力素材（mp3）
2014人教新目标英语八下unit 7《What’s the highest mountain in the world》section a 2b课本听力素材（mp3）
2014人教新目标英语八下unit 8《Have you ever read treasure island yet》 section a课件
2014人教新目标英语八下unit2《I’ll help to clean up the city parks》section b 3a-3b（含self check）课件
2014人教新目标英语八下unit 7《What’s the highest mountain in the world》section b 2b课本听力素材（mp3）
2014人教新目标英语八下unit 7《What’s the highest mountain in the world》 section b课件