TW: Discussions of Alcohol and Effects on Dopamine/Addiction
As it turns out, one of the really difficult things about alcohol is that our brains do not habituate to its effects the same way it does with other dopamine-inducing things like food, which is part of why the craving for alcohol can be so strong.
Side bar: if “habituation” sounds familiar, it may because you’ve heard how autistic brains do not habituate (adjust to) to sensory stimuli the way an allistic brain does; that’s a whole different topic, but same general idea.
A little info-diving on dopamine
Remember, one of dopamine’s primary jobs is to influence our motivation and reinforcement, which is a large part of why we struggle so immensely with mundane tasks that require dopamine like, you know, brushing our teeth.
Just a few technical things that I wanted to pull out and highlight:
Dopamine stimulation occurs in the nucleus accumbens (NAc) of our brains when seeking reward.
Dopamine operates on different “systems” and respond to different types of stimuli:
are activated only by consummatory stimuli
activated by both appetitive and consummatory stimuli
Types of motivational stimuli:
Intended to attract to that stimuli
Maintain interest in/contact with stimuli to get its benefits (ie energy and nutrients from intake of food)
Circling back to the beginning of this post, this study compared the effects of food versus alcohol on dopamine receptors and the findings are interesting. I’m going to include some excerpts in full, but basically alcohol has a more direct and cyclical effect on motivational stimuli and subsequent dopamine release.
“…two peaks of dopamine release occur in the NAc. The first peak results from the alcohol-related gustatory stimuli; the second results from alcohol’s actions within the brain. Consequently, alcohol-induced direct activation of dopaminergic signal transmission might reinforce the motivational properties of the gustatory stimuli associated with alcohol. As a result of this mechanism, the alcohol-related gustatory stimuli acquire strong incentive properties (i.e., they become motivational stimuli that induce the drinker to seek even more alcohol). Similarly, appetitive stimuli related to alcohol (e.g., extrinsic stimuli, such as the sight of a certain brand of an alcoholic beverage or the sight of a bar) also acquire incentive properties and promote the search for and consumption of alcohol. Through these complex mechanisms, the alcohol-induced dopamine release activates a secondary reinforcement chain that promotes alcohol consumption.”
Right, but that’s not all… the most important finding to me was the “nonadaptive nature of alcohol-induced stimulation of dopaminergic signal transmission in the NAc,” which essentially means the inability to habituate to the stimuli. So not only is there a cyclical component at play, but the novelty of the stimuli basically just… doesn’t wear off. And… we like novelty.
“One mechanism that may be responsible for the abnormal significance associated with alcohol-related incentives is the nonadaptive nature of alcohol-induced stimulation of dopaminergic signal transmission in the NAc. As mentioned previously, enhanced dopamine release in the NAc shell induced by conventional reinforcers (e.g., food) rapidly induces habituation, and repeated presentation of related stimuli no longer induces dopamine release. In contrast, no habituation occurs after repeated alcohol consumption. As a result of the persistent dopamine release in the NAc shell in response to alcohol, alcohol-associated stimuli acquire an abnormal emotional and motivational significance that results in excessive control over the drinker’s behavior. This excessive control constitutes the essence of addiction.”
It really is the trifecta of temptation. It’s no wonder this is such an issue for so many of us... I had no idea about the lack of habituation to the stimuli, but it makes so much sense now.
It’s why that glass of wine never loses its novelty and the very thought of it can be dopamine-inducing for me...
As always, I share this to help not hurt.
It helps me to know that there’s an added layer to the struggle I’m facing right now. And in better understanding where those struggles come from both emotionally and physiologically, I can try to honor what I need without internalized shame; I share in case it helps you with the same.