“I don’t know what’s wrong with me!” Having cast your merlot across your boss’s sweater, you futilely thrust a napkin in her direction. You’re no stranger to a drink. Why now—at the company picnic—has that second glass gone to your head?
Most of us know, for better or for worse, that drinking on an empty stomach, or while on prescription medications, can leave us unduly inebriated. Less familiar is a series of external cues that may determine how much we’re affected by alcohol and other substances. Shepard Siegel, a professor emeritus of psychology, neuroscience, and behavior at McMaster University in Ontario, coined the term situational specificity of tolerance in 1976. The idea is that the context in which we have a beer (or a cocktail, or methadone) helps determine the effects we feel—probably because our bodies prepare for the physiological reaction produced by a familiar drug when we think that reaction is imminent. Siegel describes the process as an example of classical conditioning (like the Ivan Pavlov experiment in which a bell was rung each time a dog was fed, with the result being that the dog salivated whenever he heard the bell) .
Take the panic a few years back over Four Loko, the “blackout in a can,” whose combination of malt liquor and caffeine was widely blamed for a spate of hospitalizations. At the time, Siegel argued that the real danger Four Loko posed to drinkers was not that it mixed alcohol and caffeine, but that it provided alcohol outside its usual context—with candy-like flavors, in tall, brightly colored cans that made it look like soda. A 1997 study by other researchers bears out the point: Subjects were all given the same amount of alcohol, but some of them consumed that alcohol in the form of beer, while others were plied with an unfamiliar “blue peppermint mixture.” The latter group—the group that didn’t know what was coming—did significantly worse on cognitive and motor tests .
Other seemingly innocuous factors also appear to play a role in intoxication. One study found that if you mix liquor with soda, a diet version leads to higher blood-alcohol concentrations than does regular soda (the effect seems to hinge on a digestive mechanism) . Even the shape of the glass you’re holding may affect how quickly you drink and thus how drunk you get. Researchers at the University of Bristol found that you’ll be 60 percent slower to drink a fixed amount of alcohol if it’s in a straight glass as opposed to a curved one .
Beyond the cues provided by a drink and its vessel, the physical environment in which a substance is consumed may also be important. See, for example, the study that found that subjects who were given alcohol in an office setting suffered more from its “deleterious effects” (meaning motor and cognitive impairment) than people who drank the same amount in a bar . The study also found that heart rate—which typically rises with intoxication—increased less when people drank alcohol in a familiar context than it did when the alcohol was delivered in an unexpected context. The researchers concluded that the anticipation of alcohol probably triggers a “compensatory response,” whereby the body somehow prepares for and counteracts the effects of intoxication. In other words: more classical conditioning, but with martinis.
Even with a familiar substance in a familiar place, environment can still play a role—at least if you’re a snail, and your substance of choice is an opiate. Snails given morphine had less tolerance for the drug in colder temperatures . Another study found that snails placed in a magnetic field became intoxicated more quickly than snails in a control group . Which raises another question: How do you test the sobriety of a snail?
2. Remington et al., “The Effect of Drink Familiarity on Tolerance to Alcohol” (Addictive Behaviors, 1997)
3. Marczinski and Stamates, “Artificial Sweeteners Versus Regular Mixers Increase Breath Alcohol Concentrations in Male and Female Social Drinkers” (Alcoholism: Clinical and Experimental Research, Dec. 2012)
4. Attwood et al., “Glass Shape Influences Consumption Rate for Alcoholic Beverages” (PLOS One, Aug. 2012)
5. McCusker and Brown, “Alcohol-Predictive Cues Enhance Tolerance to and Precipitate ‘Craving’ for Alcohol in Social Drinkers” (Journal of Studies on Alcohol, Nov. 1990)
6. Kavaliers and Hirst, “Environmental Specificity of Tolerance to Morphine-Induced Analgesia in a Terrestrial Snail” (Pharmacology Biochemistry and Behavior, Dec. 1986)