Animal Models of Human Misbehavior
Assistant Professor of Psychology
In psychology, animal experiments are typically conducted to study general psychological processes, which we, humans, presumably share with the species used in our research.These experiments have provided great insights into the nature of the mechanisms of learning and memory, and have established the basis to study the neurological substrate of such processes (e.g., behavioral neuroscience). Animals are also employed in the psychology laboratory to understand abnormal or pathological behavioral processes, such as phobic reactions, substance abuse, or addictive behaviors (e.g., gambling). In these cases, animal experiments are said to be models of human behavior: To the extent that we can recreate in the laboratory the conditions linked, in real life, to problematic behaviors, we can use animals to better understand these behaviors as well as devise procedures to eliminate them. But what about those behaviors that are not problematic enough to qualify as “pathological”and, yet, are a persistent annoyance or a potential health hazard? Can we develop a model in the animal laboratory of typical human“weaknesses” or misbehaviors? In this article, I will describe the research project I recently started in my animal laboratory at Hofstra, in which I am attempting to study an instance of human misbehavior that involves, on the one hand, juicy, tasty, fat (and usually fast) food and, on the other hand, antacid tablets to cope with the aftereffects of enjoying such food.
Antacid and the Glutton Dilemma
It is no secret that, in the United States,we love food. The problem is that we love it a little too much. According to the Web site of the Centers for DiseaseControl and Prevention, Department ofHealth and Human Services, “In 2007,only one state (Colorado) had a prevalence of obesity less than 20%.Thirty states had a prevalence equal to or greater than 25%; three of these states (Alabama, Mississippi andTennessee) had a prevalence of obesity equal to or greater than 30%.” Also according to this Web site, the prevalence of obesity among adults has increased from 15.0% (according to a survey conducted in 1976-1980) to32.9% (according to a survey conducted in 2003-2004).
Although genetic and hormonal differences can account for the predisposition of some individuals to obesity, only environmental factors can explain the rapid increase in the incidence of obesity in our society.Simply put, this pandemic might be due mostly to poor choices in our diet: We eat food of little quality, and we eat too much of it. According to some estimates, “[o]n any given day in theUnited States about one-quarter of the adult population visits a fast food restaurant” (Schlosser, 2001, p. 3).Because this is mostly a behavioral problem, its solution (at least, one of them) lies in behavior modification: We should teach people how to make healthier choices at the table. But, if we are to help people learn “eating skills,”it is essential that we first understand the psychological processes involved in eating behavior, specifically those that might inadvertently result in maladaptive behaviors.
One such psychological process might be related to the use of medicines to relieve pain or other noxious symptoms associated with the ingestion of certain foods. Take, for example, the use of antacids to relieve the symptoms of heartburn caused by eating fatty or spicy food. Let’s assume that Mr. X does not particularly enjoy Thai food,but happens to love delicious, yet hot and spicy tom yum. As a result of indulging in tom yum, Mr. X suffers severe heartburn, only to find relief after he swallows a couple of antacid tablets. When, a few weeks later, Mr. X goes to the same Thai restaurant with a friend, he chooses to order tom yum again, only this time taking the antacid tablets before the plate arrives.Common sense says that Mr. X would have been much better off skipping spicy food altogether, but ... how common is common sense when it comes to food? To answer this question,I conducted an online survey in June and July 2008. Fifty-three (53) people,most of them Hofstra undergraduate students, completed this survey. This sample was composed of 10 men(18.9%) and 43 women (81.1%), aged 15-25 years (n = 49, 92.4%), 26-35 years (n = 3, 5.7%), and 46-55 years (n= 1, 1.9%). Among the questions in this survey, two deserve our attention here.In line with Mr. X’s example, the first question read: “Imagine you love spicy food. After eating your favorite spicy dish, ‘tom yum,’ in a Thai restaurant,your stomach disagrees with you and you experience severe heartburn. But someone tells you there is a 24/7 pharmacy right next door, where you could buy antacid tablets. You would ...(a) get the medicine for quick relief,(b) not get the medicine and deal with the heartburn.” The answers to this question yielded a strong agreement in the use of an antacid when suffering heartburn: 41 respondents (77.4%) said they would get the medicine for quick relief, while only 12 (22.6%) said they would not get the medicine and deal with the heartburn. Even more interesting are the answers to the following question: “Answer this question ONLY if you decided to take the medicine: One week later you go to the same Thai restaurant with your friend. Your friend asks if you want to share ‘tom yum.’ You’d really like to, but your last experience wasn’t very pleasant. Suddenly, you remember the 24/7 pharmacy right next door. You would ... (a) say ‘no’ to ‘tom yum’ as it is too risky, (b) order ‘tom yum’ and wait to see if you suffer heartburn again, in which case you would get antacid at the pharmacy, (c) go to the pharmacy first and take antacid before the food arrives ... so you can enjoy‘tom yum’with no worries.” Almost half the respondents, 20 people (46.5%),would say “no” to tom yum as it is too risky; 14 respondents (32.5%) would go to the pharmacy and take antacid while waiting for tom yum, thereby enjoying it without worries; and 9 (21.0%) would wait to see if they would suffer heartburn again before getting antacid at the pharmacy.
Although it is not appropriate to consider the results of this survey as representative of the population(remember that the sample was small and mostly composed of undergraduate students at Hofstra University), it is quite informative in that it tells us that one-third of the people who completed this survey would rely on over-the countermedication in order to avoid the noxious consequences of the foods they eat. It seems like this tendency might not be news to most antacid brands,given that many of them advertise their products by appealing to potential customers with the possibility of eating all they want, without having to pay the consequences (e.g., slogans of some of their commercials leave no doubt:“Block the burn – Before it hits you” or“Bring it on”). Furthermore, this is nota problem that exclusively concerns our choices involving potentially harmful foods. For example, many of us seem to follow the same “rule of thumb” when it comes to dealing with hangovers after excessive alcohol consumption (i.e.,medicines to prevent the hangover caused by excessive alcohol intake,which must be taken along with the first drink).
The Maladaptive Heuristic
Interestingly, this heuristic or “rule of thumb” leading to reckless consumption of foods/drinks (i.e., “now that I am protected, I can eat/drink more of it”)might have its basis in an associative learning process, namely, conditioned inhibition, which in normal circumstances leads to adaptive behavior. Simply put, conditioned inhibition consists of the learning of an“if A, then no B” relationship, a relationship that in our case translates as“if M (medicine), then no E (noxious effect).” Given the causal nature of theM-E relationship, in addition to learning that M signals the nonoccurrence of E,it is also learned that M prevents E’s occurrence. The aforementioned examples can be straightforward lyreinterpreted in terms of conditioned inhibition or preventive relationships:Antacid tablets prevent heartburn, and anti-hangover caplets prevent hangover.In these two instances, M serves to assure us that E will not take place,thereby inducing a feeling of safety that,indirectly, might lead to excessive consumption of a food or drink (the cause, C), which maintains an excitatory or generative relationship with E. These relationships among events M, C andE are depicted in Figure 1.
The above scenario suggests that,paradoxically, a medicine that is effective in yielding immediate relief from noxious effects of certain foods/drinks might also interfere with learning to control the intake of those foods/drinks, with potentially harmful long-term consequences. In other words,a highly adaptive psychological mechanism (i.e., inhibitory learning)might inadvertently lead to a maladaptive behavior.