Question

Describe the discovery of the brain’s “pleasure center” and how activity in this region is currently understood to play a role in drug addiction.

Answer 1

• In 1950s, an experiment was done on the rats to study the involved stimulating discrete brain regions. (Olds and Milner, 1954)
• These experiments helped to discovered that there were a small number of brain regions in which pleasure and rewarding feelings were recorded after stimulation.
• The behavior of rats had been found that they pressed lever tens of the thousands of the succession, they started to ignore the normal need for food, water and rest to get the electrical stimulation.
• These regions were called "the pleasure center" but this name has been changed, now it is known as brain reward regions.
• The major brain circuit mediates the pleasure type reinforcement is a pathway extending from the ventral tegmental area (VTA), an area within the midbrain (a brain of the brainstrem), to a structure called the nucleus accumbens (NAc).
• Neurons in the brain communicate with each other using diverse chemical substance called neurotransmitters. One of major neurotransmitters used in the brain reward circuit is dopamine.
• Dopamine is main activity which response for the drugs.
• There are some drugs which release more dopamine, due to this activity the person feels more pleasure.