PSY 355 Psychology & Media in the Digital Age
This page was last modified on January 28, 2018
Alter's (2017) Irresistible: Some Notes
Chapter 2: The Addict in All of Us
In the early 1970s as Vietnam soldiers are returning to the US, 35% of them had tried heroin and 19% were addicted. The US Government feared the return of 100,000 addicts and their impact on the US.
Research study by Dr. Lee Robins of Washington University (St. Louis, MO) found
- 95% of heroin addicts in the US relapsed or failed to stay clean after giving up heroin
- 95% of Vietnam veterans once back in the US remained clean and did not relapse
This lead to the downfall and rejection of theories that addiction was a "personality defect" or something "inborn"
Chapter 3: The Biology of Behavioral Addictions
What is the brain's response to higher levels of dopamine (DA)?
- Increased levels of DA triggers the brain to try to restore a balance in the overall levels of DA.
- As a result it tends to do at least two things which lead to "tolerance"
- It does not release as much dopamine as it had done before (the stimulus [consumption or behavior]) is no longer as surprising or unpredictable
- It decreases the number of dopamine receptors throughout the brain
Research by Kent Berridge in the 1990s and 2000s found that addicts don't just like the effects of their addiction, they also have intense cravings or wantings even if their addiction substance/behavior no longer gives them any pleasure. There are two different feeling states: liking vs. wanting.
- Addicts, therefore, must increase their use of the substance or the behavior in order to achieve the same level of pleasure.
- The mesolimbocortical system which uses DA becomes particularly sensitized on a long-term basis to the effects of DA. This, in turn. leads to addicts craving even when they know that the substance/behavior is both harmful and no longer enjoyable.
- More specifically, the brain becomes hyper-reactive particularly to the environmental cues that are associated with the substance/behavior.
- Recall the Vietnam Veterans study: since these veterans were no longer in the same situations as Vietnam (jungles, being shot at, hearing the sounds of explosions or helicopters, etc.) the environmental cues for drug use were not there and their craving for heroin tended to go away.