Is alcohol a stimulant?
When people take alcohol they behave in a certain way. A way that amuses themselves as well as others. They start to talk a bit louder; bit excessively; bit aggressively; bit jovially. Some start to sing, and dance, too, sometimes. People who do not generally speak much English start to speak in English, while those who do not speak Sinhala start speaking Sinhala. Inhibitions seem to have been thrown away. People seem to be animated and quite stimulated.
Apparently alcohol seems to activate the user. Now alcohol, as we all know, acts through the brain. It reaches the brain, acts on its cells and causes its effects. So alcohol seems to stimulate the brain.
But is alcohol a brain stimulant? Alcohol is a potent CNS depressant, any science book would say so. CNS means central nervous system: The brain and the spinal cord. Hang on! How can that be? We just concluded that alcohol seems to be a brain stimulant. But when we check the chemical properties of alcohol, we find out that alcohol is a powerful brain depressant. Opposite of stimulant.
If alcohol is a powerful brain depressant, a chemical that slows down the brain, how can people who take alcohol appear to be stimulated? Brain depression would cause the person to talk slowly, walk slowly and feel depressed. Instead people after taking alcohol talk loudly, dance enthusiastically, and feel lively. How can we explain this?
Some people who believe they know (pseudo) science, claims that alcohol depresses the inhibition centres in the brain that inhibit our social behaviour. No scientist has ever found a shred of evidence on these so-called ‘inhibition centres’. Hence the confusion remains.
Before trying to explain that, let us explore another confusion: Timing of the so-called effects of alcohol.
How quickly does alcohol exert its effects on the brain?
We see that sometimes people start showing the effects of alcohol as they start to plan an alcohol-drinking session. Many would show some signs of stimulation while they open the bottle, pour it and start drinking. Most would show some signs of stimulation after few drinks.
For alcohol to exert its effects it needs to reach brain. The alcohol that is absorbed from our stomach and intestine first has to pass through liver. The liver removes most of the alcohol. And that is why liver quickly gets damaged with, even single, alcohol consumption. Now when the liver removes alcohol from blood to a large extent, it takes a while for the alcohol concentration to build up in the blood. Therefore it takes at least 30 minutes, if not more, for enough alcohol to reach brain.
Now how can we explain people showing signs of alcohol effects during first few drinks? And there is no way to explain the behaviour of people who start showing signs of alcohol effects even before the first drink.
Why effects of alcohol seem to be readily reversible?
Okay, now from one confusion to another: Why do people suddenly behave sober at the peak of intoxication at certain times? The one, who was shouting in filth, instantly becomes well-behaved when the Police appear on the scene. However when the Police leave and he goes home to his wife and children, he is very aggressive again. If the aggression is due to alcohol, then the alcohol concentration in the blood must be fluctuating heavily under the influence of what is happening in the surrounding environment.
Let me summarise our three confusions:
- Why effects of alcohol seem to be readily reversible without change in blood alcohol concentration?
- How come alcohol appear to exert its effects on the brain very quickly (sometimes even before drinking is started) while it takes a while for the blood alcohol concentration to build up?
- How can we explain alcohol’s apparent stimulating effects knowing that alcohol is a powerful brain depressant?
Perhaps the answer is same for all these three questions. Let us explore one more issue, before trying to answer these questions.
What is ‘learning’?
Learning is something we do all the time. Education, too, involves some complex learning. However let us explore the psychological phenomenon called ‘learning’.
One of the simplest forms of learning is ‘association’. This was classically demonstrated by a physiologist called Ivan Pavlov over a century ago in Russia. He gave meat powder to dogs in his lab after ringing a bell. And he did this again and again. After a while when he rang the bell without any meat powder, the dogs started to salivate. Just imagine! A dog salivating when a bell is rung!!
As the bell ringing and salivation (due to the smell of meat powder) were coupled together few times, the dogs learnt to salivate at the clang of the bell. This is learning a new behaviour (salivating in response to a bell ringing) with association (bell and meat powder). Not only new behaviours, new emotions, too, can be learnt.
Now let us explore the application of ‘learning’ in alcohol drinking.
We do not drink in isolation under despairing conditions generally. At least not in the beginning of our drinking career. We usually drink with friends, at moments of joy, friendship and celebration. We have tasty food, nice environment, great things to talk, cracking jokes to share and wonderful memories to recall with others. All this make us feel good. Feel pleasure. Feel stimulated. Behave joyfully. Talk a lot. Sing a song. Dance a little tune. Have fun.
Now we couple these joyful moments with alcohol. Again and again. After while alcohol alone would bring us joy, pleasure, songs, nice memories. We seem to have our brains stimulated. But what we do not understand is that this brain stimulation is the ‘salivation’ and alcohol is the ‘bell’! Because this is real. At least that is how we feel. We really feel the fun we have, the joy we experience. We really behave as if we are stimulated. We really are the ‘dogs’ in the lab of Pavlov.
There are many more factors operating in behaviour after alcohol other than learning. We would learn about them in the future.
What an anti-climactic end to this discussion! So we act the ‘Pavlovian Dog’, and we ‘salivate’ when the ‘bell’ is rung. The only difference is that the ‘bell’ is alcohol. The ‘salivation’ is the little nonsense we do and feel. The ‘dog’ is us. And ‘Pavlov’ is the Alcohol Industry.
Dr. Mahesh Rajasuriya
Dr. Rajasuriya is at present a Senior Lecturer at the Department of Psychological Medicine, Faculty of Medicine, University of Colombo as well as a Consultant Psychiatrist at the University Psychiatry Unit, Ward 59, National Hospital of Sri Lanka, Colombo.