The transformation of behavior that is taken to be undesirable, into symptoms of diseases, is one of the main ways in which looping effects are generated. In the following, a simple model aimed at describing how this transformation takes place is put forward, and the reason why this process is subject to the looping effect is shown.

2.3 A model for the genesis of a disease

An important clarification can be made regarding the looping effect, taking the three elements cited earlier into consideration (biological causes, set of symptoms and patient behavior), along with the role that each of these has in identifying a disease.

Firstly, a scenario in which there is no looping effect is considered (Figure 1). In stage 1, a diffuse set of symptoms is perceived in a group of patients. Next, biological causes that explain a portion of the initial set of symptoms are postulated. The transition from stage 1 to stage 2 can be called biologization. Lastly, only the portion of the set of symptoms for which a biological basis can be ascribed is used to make the diagnosis. The transition from stage 2 to stage 3 can be called reduction. In this scenario, the looping effect is ignored.

Identifying a disease, which may be the result from years of research, ultimately isolates a set of symptoms that are relevant in making the diagnosis (stage 3). Laboratory and other tests for this disease are used to link the symptoms. This scenario is not intended to be exhaustive: after stage 3, the healthcare team's work evidently continues. A patient who presents a set of symptoms that roughly corresponds to the set in stage 3 is marked (in the sense discussed earlier) for tests to be performed in order to identify the presence of biological causes that are commonly associated with that set of symptoms. If the clinician concludes that the results confirm the presence of these causes, the diagnosis is made and the patient is again marked, this time for the treatment process.

Cases in which there is a loping effect are now considered (Figure 2). It should be noted that here, the "symptoms" are purely behavioral, and any biological bases found for sustaining them are always doubtful. The looping effect occurs in passing from stage 3 to stage 1, when a diagnosis causes a patient to change his behavior and thus, change the set of "symptoms" for that condition.

Hacking (1999; 2007) stated that in this case, the people thus classified are "moving targets", i.e. in changing their behavior, they even end up changing the stereotype of the classification. Hence, they are not stable subjects of knowledge. Jonathan Tsou (2007) criticized this point, through claiming that no matter how much an individual changes his behavior, he will be incapable of changing the biological causes of his condition. Tsou made particular reference to the biological causes of schizophrenia (excess of dopaminergic activity in the mesolimbic pathway): no matter how much a schizophrenic patient changes his behavior, he will be unable to diminish the dopamine concentration in his brain. It is possible that Tsou considered that this type of looping effect was as absurd as the idea that a cancer patient would be capable of removing the tumor just by "force of thought" or at least by behaving as if he had removed the tumor.

However, the hypothesis that certain sets of symptoms described in the literature do not have unambiguous biological causes and thus do not constitute diseases in the biomedical sense needs to be taken into consideration. Tsou himself recognized that this was perhaps the case in a large proportion of the disorders listed in the DSM-IV (Tsou, 2007, p. 339n). It is very likely that ADHD fits into this group (Timimi, 2002, p. 88).

3 Attention-deficit hyperactivity disorder (ADHD)

In order to think about the significance of ADHD for children, it first of all needs to be understood what the disorder is, what criteria are used for diagnosing it and how its historical evolution has taken place.

In some academic circles, ADHD is considered to be the commonest psychiatric diagnosis during childhood. It is characterized by three main symptoms: lack of attention, impulsiveness and hyperactivity (Vasconcelos, Junior, Malheiros et al., 2003). Chart 1 lists the DSM-IV criteria for diagnosing ADHD (DSM-IV-TR, 2002).

ADHD was known by several names over the course of the twentieth century. Among these were "lethargic encephalitis", "minimal cerebral damage", "minimal cerebral dysfunction", "hyperkinesia", "attention deficit disease" (ADD) and "attention-deficit hyperactivity disorder". For each of these disease categories, sets of similar symptoms depicting deficits during childhood have been described. The following are some of the most cited symptoms, which are common to all these names: low performance at school, extreme extroversion, violent behavior, incapacity to complete tasks, thievery, disturbed sleep patterns, morality inconsistent with the age and forgetfulness (Rafalovich, 2001).

The idea that agitation, low concentration and impulsiveness among children are medical phenomena is recent. Interest in children who presented low attention capacity and hyperactivity began at the start of the twentieth century when a pediatrician, Frederick Still, described a group of children who had an abnormal incapacity to maintain concentration, together with restlessness and irritability (Still, 2006 [1902]). The characteristics of hyperactivity and lack of attention among children were only correlated with each other with the emergence of the diagnosis of minimal cerebral damage, after the epidemics of encephalitis during the first decades of the twentieth century (Timimi, 2002).

During the 1930s, the action of psychostimulants for reducing restlessness, hyperactivity and behavioral problems among children was discovered. In the 1940s, Strauss suggested that hyperactivity in the absence of histories of abnormalities in the family could be considered to be sufficient evidence for a diagnosis of cerebral damage (Timimi, 2002).

However, as the years went by, no organic lesions were found in these agitated children. Thus, from 1960 onwards, the term "minimal cerebral damage" fell into disuse. On the other hand, even though this hypothesis was abandoned, there was increasing interest in syndromes that were defined behaviorally. Researchers started to believe that this syndrome was caused by some type of cerebral dysfunction. In the second edition of the DSM, the disease was called "hyperkinetic reaction of childhood" (Timimi, 2002).

The third edition of the DSM was published in the 1980s, and the name became "attention deficit disorder" (ADD). The problem could be diagnosed with or without hyperactivity symptoms and was defined using three lists of symptoms: one for attention deficit, one for impulsiveness and one for hyperactivity. In the fourth edition of the DSM (DSM-IV), the criteria for the diagnosis changed again, this time towards a two-dimensional model: attention deficit in one subcategory and hyperactivity and impulsiveness in the other. It is important to highlight that, in each revision, the number of children with characteristics of the disease increased. The change from DSM-III to DSM-IV increased the prevalence of the disorder by around two thirds (Timimi, 2002).

The prevalence of ADHD has been investigated in many countries, and studies using the criteria of the DSM-IV have tended to find prevalences of 3-6% among children of school age in the United States. In Brazil, the prevalence rate in studies of this type has been found to be 3.6 to 5% of the school-age population (Andrade and Scheuer, 2004). The proportions of the disorder between boys and girls, according to epidemiological studies, has ranged from 2:1 in population based studies to 9:1 in clinical studies, respectively (Rohde and Halpern, 2004).

In relation to diet, some studies have suggested that certain preservatives like sodium benzoate and artificial food colorants may exacerbate hyperactive behavior among small children (Barrett, 2007). Another nutritional factor relating to this disorder is low serum ferritin levels, which indicate iron deficiency. According to studies on this subject, iron modulates dopamine and noradrenaline production: the quantities of these substances in individuals with ADHD are unbalanced (Konofal, Lecendreux, Deron et al., 2008).

However, it is important to emphasize that in speaking of neuron and neurotransmitter development from the point of view of neuroevolution, a certain level of hyperactivity in children up to the age of around four to five years is acceptable, given that the prefrontal region (the location for the behavioral "motor brake" in humans) only becomes completely developed at this age (Rohde and Halpern, 2004).

The treatment generally indicated by healthcare professionals encompasses psychosocial and/or psychopharmacological interventions. For psychosocial interventions, an educational approach is recommended, providing clear and precise information to the family regarding the disorder. Furthermore, school support is advisable, through implementing a consistent daily routine, physical activity and individualized attention, whenever possible (Zavaschi and Rohde; Lorenzon et al., 2004).

In relation to pharmacological treatment, stimulants are considered by most professionals and researchers to be the first-choice medications. In Brazil, the only stimulant approved and available on the market is methylphenidate, under the commercial names Ritalina^® (Novartis) and Concerta^® (Janssen-Cilag). In cases of comorbidities, intolerance or lack of response to stimulants, tricyclic antidepressants are often used, for example imipramine (Zavaschi, Rohde, Lorenzon et al., 2004), under the commercial name Tofranil^® (Novartis).

4 Behavior and symptoms

It can be seen that ADHD is a recent phenomenon and that, prior to the twentieth century, characteristics that today are considered to be symptoms, such as restlessness, impulsiveness and hyperactivity, were regarded as normal behavior. Thus, it can also be seen that today, scientific knowledge and healthcare practices have made the threshold between health and disease, i.e. between normal and pathological, very tenuous. Individuals merely have to present behavior that society in general deems undesirable for them to be labeled as "depressive", "anxious", "crazy" or even "hyperactive". This comes about because the natural highs and lows of life and the correlated behavioral patterns that were previously considered to be normal have been converted into pathological states (Blech, 2005).

According to Georges Canguilhem (1982), science describes normal human beings as those that fit within preestablished standards that are determined through averages. However, he posed a question: should deviations be considered to be abnormal? The models for normal individuals are produced from statistics, but in Canguilhem's view, real individuals diverge from this model and this is what makes them different from each other.

With regard to children, the learning targets established for each age group at school show the great influence of the positions taken. Most children learn to read at a certain age; those that do not start to read together with the others can easily be regarded as deviant. The characteristics of ADHD are generally perceived at school, and children are referred to healthcare professionals from there. The words of a teacher about a "problem student" taken from the book by Cecília Collares and Maria Aparecida Moyses (1996) illustrate this point: "she's way behind. I think that she should be referred to the health services or a psychologist, because she has something; she's way behind. From her size and age, I think she should have learned by now. She's still at the pre-syllabic stage." (p. 250).

According to Collares and Moyses (1996), school is a place that harbors prejudice relating to students, their families and school failure. Failure to keep up with the institutional standards always falls onto students and their parents:

The above citation is no more than a repertoire of reductionist explanations for learning problems. According to Richard Lewontin (Lewontin, Rose and Kamin, 2003), reductionists are people who try to explain the properties of complex systems (such as learning) by focusing on just a few aspects. From a reductionist perspective, the problem of non-learning lies in isolated characteristics such as skin color, socioeconomic level, place of origin and presence of diseases.

Disease has been used as an explanatory factor for individuals' deviations within society, a phenomenon that can be called biologization. Thus, properties are reified, i.e. they gain localization and are treated medically. That is, they are seen as caused by events in individuals' brains that are associated with modifications in the quantities of certain chemical substances (Lewontin, Rose and Kamin, 2003).

This process of biologization, especially of conflicting social issues, generally takes place at times of great social tension. For example, this occurred during the 1960s, when science "proved" that white men were genetically superior to black men, in intellectual terms; and that women and men presented intellectual differences because of neurological differences that were also genetically determined (Collares and Moysés, 1996).

Biologization of non-learning is very common within the school environment, and it causes responsibility for academic failure and dropping out of school to fall on illnesses. In biologizing social issues, the entire social system becomes exempted from responsibility. At school, the lines of a political-pedagogical discussion are shifted to medical causes and solutions, which are inaccessible to education (Collares and Moysés, 1996). Thus, according to some teachers, doctors and parents, as well as the children themselves, very active individuals, who do not pay attention as they should, present some type of health problem (Conrad and Schneider, 1992).

Dealing with this undesirable behavior as a medical problem was, and continues to be, well accepted within society, and there are various reasons for this. For doctors, the therapy is relatively simple (prescription of a medication) and the results may be excellent, from a clinical point of view. In turn, the diagnosis of ADHD indicates that this is a disease that can be treated, which diminishes the extent to which parents can be blamed, and means that parents may regard the diagnosis favorably. In addition, the medication frequently makes the child less agitated and hyperactive in the classroom and often facilitates learning, thereby also resolving the problem at school (Conrad and Schneider, 1992).

Hacking (2007) writes that behind every classification, there is a structure that encompasses five primary factors: the classification, individuals, institutions, knowledge and specialists. The classification in itself generates the kinds of people. Children with ADHD are one kind of person, formed by individuals who share the same problem. This group of people has a name and their characteristics are determined as a function of this name. Individuals (or their families in the cases of ADHD) often only start to see certain characteristics of the classification as problems after receiving the diagnosis.

Institutions confirm the existence of this classification and are a means of legitimizing that kind of person. One example of an institution in this case is the DSM-IV, which provides a means of legitimizing and justifying the diagnosis of mental disorders. The DSM-IV presents a series of behavioral characteristics, as can be seen in item 3, which indicate whether the child presents ADHD. These criteria are interpreted by specialists, through descriptions from the child's family and educators.

Thus, knowledge and specialists have the power to decide who is ill and who is not; and who presents ADHD and who is normal. The diagnosis for the disorder is essentially clinical; there are no laboratory tests or imaging examinations that can aid in this decision. Specialists only have their technical knowledge, the criteria of the DSM-IV and information coming from people with links to the child available for outlining the diagnosis and indicating the appropriate therapy for the case.

After the diagnosis has been made and, generally, after medication has been prescribed, these children go back home and back to school labeled with a psychiatric disorder. In section 2.2, it was mentioned that the classifications interact with the individuals classified, and that this interaction takes place through the looping effect. The tendency is to think that this looping effect only occurs in relation to people who are aware of the label that has been given to them, i.e. people who understand the significance of their disease.

What about individuals who are unaware of the classification, such as people who cannot understand the language, babies or small children (Hacking, 2006)? Children are often diagnosed with ADHD before they are able to understand its significance. In such cases, it can be said that the feedback effect is impossible. However, Hacking (2006) stated that the looping effect involves much broader units, such as the family, and in the specific case of ADHD, it may also involve the school. It is impossible to believe that this label will not have an influence in many decisions that the family, and subsequently the adult diagnosed with ADHD during childhood, will make.

From a well-established diagnosis, any unexpected behavior by the child comes justified by the disease that is presented. The attitudes of people around this child become modified because of the diagnosis and the characteristics that are taken to due to the disease. This change affects children with ADHD and makes them see themselves differently, thus giving rise to the looping effect.

The words of a mother, retrieved from the study by Uribe and Roja (2007), illustrate how a diagnosis, i.e. a classification, may change the environment within which the child lives:

From the moment when someone enters the list of ill people, a treatment for this condition needs to be available. In general, it is believed that children with ADHD should receive medication in order to correct their deviant behavior, so that they can continue to live within society and enter within its standards and rules again.

Peter Conrad (Conrad and Schneider, 1992) called this control over deviation and promotion of social conformity social control. Individuals who strayed from the standards would have to be controlled, so that society, or the family or the school could return to its "normal state". Conrad maintained that there were formal and informal levels of social control. Informal control would include both self-control (internalization of standards, beliefs, morals and so-called "conscience") and relational control (day-to-day relationships), and would inhibit individual behavior that was considered to be deviant. For example, somebody could go out from their home with a desire to pick a fight with the first person that he might meet on his way; however, he would not do so, both because of his moral beliefs and conscience and because of what other people would think and say about such an act.

Formal social control encompasses institutional forms of control, such as the legal, police, educational and social care systems and even the healthcare system. These are the "official" forms of control: the ones that nobody is capable of questioning unless he is a specialist in this field. Because these are so well accepted and, in the case of healthcare, because it is backed by science, their consequences are generally much more profound and long-lasting, both for individuals and for society and the environment in which these individuals live (Conrad and Schneider, 1992).

Thus, receiving a diagnosis of ADHD from an official institution leads to a change in behavior, not only among the individuals with the diagnoses but also throughout their social network, which in turn also ends up influencing these individuals, and so on. This leads to the suggestion that a looping effect with positive feedback consists of acceptance and reinforcement of the characteristics through which the diagnosis was made, which should then be treated so that the environment returns to normality.

6 Final remarks

It is very common to think that various forms of distress, unwellness and psychological disorders can be caused, treated and cured solely through biological means (Legnani and Almeida, 2004). The practice of transforming social problems into pathological conditions takes away the responsibilities for deviations from the hands of the system, family, individual and society in general, thereby turning them into diseases that can be treated with a "magic bullet", to use Lewontin's term (Lewontin, Rose and Kamin, 2003).

Agitated or inattentive behavior among children may become considered deviant. Schools that are overloaded with children are not in a position to deal with such situations and often transfer the responsibility for children who are considered to be problematic, to the healthcare system. In turn, the healthcare system is structured to diagnose and treat diseases and, for this reason, it generally provides a diagnosis and medication for individuals who seek care.

The healthcare ideal of present-day so-called scientific medicine (which defines health as absence of disease) conceives of the body as a machine that can be repaired if it should happen to present a defect. This model does not take into consideration the fact that there is no perfect body machine in relation to another that could be considered defective, i.e. there is no perfect machine with which the others can be compared (Martins, 2004). 

The highly subjective nature of the definition of ADHD enables a series of interpretations, thus turning this diagnosis into a repository for a variety of problems (Timimi, 2002), which are generally not resolved within the sphere of school. Because of this subjectivity, there is a risk of treating "normal" children as "ill", thus leading these children to incorporate this disease and consider themselves really to be ill. They may thus regard themselves, even after reaching adulthood, incapable of accomplishing day-to-day activities that are performed by other individuals who are considered to be "normal".

Despite the looping effect with positive feedback that occurs in ADHD and the social control resulting from this condition, the diagnosis may present a beneficial side, consisting of "freeing" both the child and his own family from blame. The family thus ceases to be regarded as being to blame for the undesirable behavior. The child ceases to be labeled as badly brought up and becomes labeled as ill (Silva, 2009). His problem becomes located in the brain, in neurotransmitters, and is therefore relatively easier to "cure" or control.

It seems to us that the social tolerance for people who are different is very low, to the point that people prefer to be called mentally ill, rather than slothful or disorganized. A process may be taking place in which the illness is tolerated because it can be treated and controlled, whereas it is believed that personality (taken to be the factor that generates behavior) is less palpable and more difficult to control. To treat individuals with psychiatric disorders today, internment and confinement are no longer used but, rather, medicalization. Bodies are tamed not through physical confinement in a lunatic asylum, but through psychological confinement using psychoactive drugs that model conduct, habits and thoughts (Caponi, 2009).

AUTHORS' CONTRIBUTIONS

This article derives from the master's degree project of Fabíola Stolf Brzozowski, under supervision from Prof. Dr. Sandra Caponi and with theoretical contributions from Jerzy André Brzozowski.

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