Behavioural disorders in children and adolescents: Definition, clinical contexts, neurobiological profiles and clinical treatments

Behaviour represents the set of behaviours that defi ne the way an individual acts and reacts in relation to his or her surroundings and the individuals who are part of them. It is therefore the set of external manifestations of an individual that defi ne the temperament (understood as the set of innate, genetically determined tendencies of the individual to react to environmental stimuli in certain ways) and the character (understood as the unitary and organized complex of the psyche in direct relation with the environment) and the experiences (the emotions recorded in the memory of interactions) and therefore the personality [1].

therefore the set of external manifestations of an individual that defi ne the temperament (understood as the set of innate, genetically determined tendencies of the individual to react to environmental stimuli in certain ways) and the character (understood as the unitary and organized complex of the psyche in direct relation with the environment) and the experiences (the emotions recorded in the memory of interactions) and therefore the personality [1].
From the ashes of structuralism, always starting from the introspective assumption, the behaviourist current was born, which focused on manifest behaviour. In particular, Pavlov  focused on the mechanism of conditioning (1903), starting from the Russian studies of Secenov's "refl exological current" (1860). Like him, in the same years, so did Bechterev.
Famous is his classic experiment with the dog (so called "the dog"). classic conditioning) to demonstrate the existence of the conditioned/conditioned refl ex, i.e. with a natural stimulus (conditioned stimulus) one is able to provoke the occurrence of a certain involuntary reaction (unconditioned response), such as salivation, pupillary contraction or eye closure: <<if we associate a conditioned stimulus (sound) with the unconditioned stimulus (food), a suffi cient number of times, the dog will tend to associate the 2 stimuli, and give them the same meaning, According to this author, the acquisition of language takes place precisely through conditioning. Thorndike (1874Thorndike ( -1949, later on, focused on the mechanism of learning, not using introspection but instead favouring observable behaviour. On this basis he elaborated three laws: a) fi rst law (of frequency), according to which learning is gradual and improves with repetition; b) second law (of contiguity), according to which the shorter the interval of time between stimulus and response, the greater will be the learning; c) third law (of effect), according to which if the stimulus produces a response that produces a new behaviour similar to the previous one, the learning will be greater. Always Thorndike then coined the "halo effect" to designate a psychological attitude consisting in the automatic tendency, during the evaluation of a person, to associate to a positive quality (e.g. physical beauty) other positive aspects without any real correlation with that quality (e.g. sympathy, intelligence, competence or reliability). It can be considered an important and widespread example of "bias" operated on an ineffective heuristic basis. Hull  still concentrated on the themes of learning and behaviour, theorizing the assumption that the force of habit is directly proportional to the number of associations between stimulus and response that have been reinforced. Skinner  then focused on the cause-effect mechanism, introducing the principle of reinforcement. operative -active conditioning): a) human behaviours are predictable and controllable through an appropriate management of stimuli and reinforcements (shaping); b) operative or associative learning foresees the active, direct and conscious participation of the subject who acts as a consequence of positive reinforcements (reward) or negative reinforcements (punishment), as can be seen from the mouse experiment with cheese: <<a hungry rat, which moves in the Skinner Box, is conditioned to lower a lever, when it receives food, while it receives a shock if it stops touching it>>; c) Skinner fi nally takes his cue from Thorndike who years before had already invented the Puzzle Box: a cage from which a hungry cat learns progressively lowering with one paw the lever, which acts as a handle on the exit door, to reach the food outside. They both assumed that to learn you had to make mistakes, make mistakes; however, Skinner perfected this theory, thanks in part to his media success [1].
At the base of human action, however, are the emotions, understood as psychic processes provoked by a relevant eventstimulus able to stimulate physiological and bodily changes), which nourish needs and necessities according to a precise scheme (which originates from the unconsciousness) [2].
The recent interest in the study of emotions stems from the critique of Western thought, which has always contrasted reason with emotions, where in the former the noble part of man resided and in the latter the instinctive animalistic part to keep at bay. Today, different spheres of knowledge lead us to consider emotions as a form of cognitive and emotional communication. Emotional attachment to other individuals and the various types of emotional involvement infl uence a relevant portion of human behaviour [3].
Precisely for these reasons it is necessary to introduce the present work by briefl y considering the evolution of thought on emotions, according to the main theories [4][5][6][7][8][9][10]: The classical theories a) James-Lange's theory: The psychologist James and the physiologist Lange, at the same time independently of each other, proposed similar theories on emotion, which is why it is called James-Lange theory. Their theory was opposed to that of common sense: According to them we do not weep because we are sad, but we feel sad because we cry; we do not tremble because we are scared, but we feel fear because we are shaking, and so many other examples. So according to this sequentiality, the emotional reaction depends on how the sensations are interpreted on a physical level.

b)
The Cannon-Bard theory: Cannon, in 1927, published a critique of the James-Lange theory. Cannon discovered that the same state of activation of the sympathetic nervous system can be present in many different emotions. Thanks to these studies, Bard (1929) further elaborated this theory, according to which it is the thalamus that plays a critical role in emotional experience. For Bard, the nerve impulses that make sensory information pass through the thalamus are then retransmitted. He receives this input upwards in the cortex (causing a subjective emotional experience) and downwards in the muscles, glands and visceral organs (producing physiological changes). Cannon and Bard argued that the subjective and physiological components of emotion are simultaneous, disagreeing with James, who argued that physiological modifi cations precede and activate subjective states.

c)
Schachter-Singer's theory: According to Schachter, one feels an emotion when choosing a cognitive label to designate a diffuse state of physiological activation to which we give the name of a particular sensation. Unlike James, Schachter does not advance the hypothesis that physiological sensations are emotions and that each emotion is accompanied by differentiated physiological modifi cations. Schachter suggests, instead, that the state of activation is only a generalised activation of the autonomic nervous system, until we connect it cognitively to an interpretation by associating it with an emotion. For example, the judgment: "I have stomach cramps because this man is threatening me" will be followed by a feeling of fear. However, no emotions will be felt if external stimuli are not cognitively associated with the state of activation. It may happen, for example, that I notice that I have a stomachache and that the individual seems very irritated, but these two unrelated events do not cause any emotion.

Modern theories
a) The neurobiological approach: In 1980, Zajonc argues that emotions can be provoked even in the absence of high cognitive or perceptual involvement. Sometimes, for example, we feel an immediate sympathy for someone crossing a room or an aversion to someone else, for the way they answer the phone. In 1998, Le Doux confi rmed how anger and fear can be directed from the thalamus to the amygdala, making an immediate evaluation possible and often producing an immediate attack/ fuge response, confi rming what Zajonc said.
b) The cognitivist approach: According to Lazarus (1982) for an emotion to appear, thought is necessary and suffi cient, that is, cognitive evaluation. Lazarus hypothesizes that our emotional experiences are always the result of thought, that is, of a cognitive evaluation of the meaning of the events responsible for our state in the here and now. He also argues that before we experience a normal emotion we evaluate events quickly or unconsciously, basing our thoughts on minimal information, using irrational premises. Cognitive evaluations that form very quickly and provoke an instantaneous emotional response such as "The wolf is about to attack me" are called warm cognitive processes and are the precursors of emotion. Other, slower cognitive processes such as "That wolf has a brown fur" do not arouse any emotion and are therefore called cold cognitive processes. This is why hot cognitive processes always precede emotions. Thanks to the work of different authors it has been understood that some emotions can be defi ned as innate, which is why the dichotomy between sensation and cognition is overcome.

d)
The attachment theory [11]: Emotions are at the basis of the interactions between caregiver and child, which will determine the onset of almost all known psychopathologies of the evolutionary age. As a result of these interactions, therefore, different styles of attachment can be formed in the child, as has been demonstrated in the Strange Situation (a procedure carried out by Bowlby [12] and his assistant Ainsworth, in which the child with his mother is introduced into a room full of toys. At various times the child is left alone or in the company of a stranger and then reunited with the mother to study the child's behaviour. Through these observations conducted in a welldefi ned setting, it has been possible to identify four patterns of child attachment: safe attachment and insecure attachment (with three types: avoidable, ambivalent and disorganised).
From this we understand how emotions play a fundamental role in the interaction between adult and child by infl uencing important portions of behaviour. By expressing his or her emotions to the caregiver, the child is able to tune in to his or her needs in order to satisfy them (suffi ciently good parent) [13], this allows the child to feel protected, nurtured and loved and therefore to be able to grow and develop.
Citation: Perrotta  Remaining on the subject of "attachment", it is easier to see the importance of basic emotions (anger, fear, sadness, disgust, contempt, surprise and joy) and how necessary they are for the child to be able to communicate with the reference fi gures in order to see their needs satisfi ed. Precisely for this reason, below, we will give examples that can show how emotions and anger in particular can be considered in a continuum between functional, non-functional and disfusional, producing behaviours from the most adaptive to maladaptive to pathological ones: Adaptive situation for psycho-emotional development: In the case that the treatment satisfi es the child, we will fi nd a child who is balanced, safe, willing to explore the world of learning, who may have matured the management of frustrations and live his or her emotions, including anger in a balanced way.
For example, when a child is told no, he or she will experience a common sense of frustration that will lead him or her to express anger, in turn, this emotion expressed towards the care-giver may lead him or her to console the child, thus containing the anger itself. From this simple example, we realise how over time this type of interaction can modulate the system of anger and its behavioural expression, as well as all other emotions. We therefore understand how any emotion as a form of communication and its modulation as feedback may or may not favour the child's emotional and cognitive evolution.

The psychosocial infl uence on psycho-emotional development:
We consider less protective contexts for the child and his/

Dysfunctionality:
The last example is when the child lives, through violence and abuse [14], a continuous experience of rejection. This constant dissatisfaction with security generates in the child: emotional insensitivity, apathy, sense of inadequacy, making him or her live himself or herself as something inadequate, sick, incapable. In this possible situation we know that the child will not be able to live the emotions connected to these experiences, otherwise his survival would be lost, thus favouring a process of dissociation and removal [15]. We understand how the child's lack of emotional development will not allow him to develop those skills useful to sociality such as empathy, identifi cation, moral sense, the limit of freedom. In this situation, there is a great increase in the possibility that the lack of modulation of anger can produce aggressive behaviour, fi rst and then violent behaviour with social deviance, which could lead to a real psychopathology.

Clinical and psychopathological profi les
Behavioural disorders include a series of behaviours defi ned as "externalising", as they include behaviours in which internal discomfort is directed outwards through dysfunctional conduct  are prevalent. In particular, reference is made to "intermittent explosive disorder", "conduct disorder" and "oppositional-provocative disorder"; however, a neurodevelopmental disorder called "attention defi cit hyperactivity disorder" also falls into the category of behavioural disorders [28]. In detail:

1)
The intermittent explosive disturbance: It refers to a behavioural picture where aggressiveness is dangerously acted out of the person's control and without adequate connection with the extent of the events taking place. The disorder is characterised by recurrent behaviour of explosive aggressiveness, verbal or physical, towards people or things that are potentially destructive and capable of causing serious damage. The aggressiveness acted in the intermittent explosive disorder is not only impulsive and uncontrolled, but clearly disproportionate to any stressful event or contingent provocation. People suffering from such disorders may experience episodes of exaggerated, unjustifi ed and potentially damaging aggression for themselves or others, but such behaviour is a manifestation of a depressive or personality disorder and not primarily an expression of an inability to control impulses.

2)
Conduct disorder: The main characteristic of this disorder is the systematic and persistent violation of the rights of others and social norms, with very serious consequences in terms of school and social functioning. Children and adolescents can show overbearing, threatening or intimidating behaviour, intentionally triggering fi ghts, stealing objects by confronting the victim and forcing the other to suffer violence, even sexual abuse. The symptoms of the disorder are: assaults on people or animals; often bullies, threatens, or intimidates others; often starts physical fi ghts; has used a weapon that can cause serious physical harm to others (e.g. a stick, a bar, a broken bottle, a knife, a gun); has been physically cruel to people and animals; has stolen by confronting the victim (e.g. assault, mugging, extortion, armed robbery); has forced someone into sexual activities; destruction of property; serious violations of rules.

3)
Oppositional-provocative disorder: It involves problems of self-control of one's emotions and behaviour. In such disorders the described problems are expressed through behaviours that violate the rights of others, as in the case of aggression, destruction of property, or that place the person in sharp contrast with social norms or fi gures representing authority. Emotions such as anger and irritation, together with controversial and defi ant behaviour, prevail. The frequency of the provocative oppositional disorder is higher in families where a parent has an antisocial disorder and is more common in children of biological parents with alcohol addiction, mood disorders, schizophrenia, or parents with a history of attention defi cit hyperactivity disorder or conduct disorder. Oppositional provoking disorder is characterised by the frequent and persistent presence of an angry/irritable mood (he often gets angry, is often touchy or upset, is often angry and resentful), polemic/provocative behaviour (he often quarrels with people who represent authority, often openly challenges or refuses to respect the rules, deliberately irritates others, blames others for his own mistakes), vindictiveness. These symptoms must occur when interacting with at least one person other than a sibling and are often part of problematic ways of interacting with others. -is often unable to play or engage in leisure activities quietly; -he is often "under pressure", acting as if he were "powered by a motor" (for example, he is unable to stand still, or feels uncomfortable doing so, for a prolonged period of time, such as in restaurants, during meetings); -often speaks too much; -often "shoots" an answer before the question has been completed (for example, he completes sentences said by others; he cannot wait his turn in conversations); -often has diffi culty waiting for his turn (e.g. while waiting in line); -often interrupts others or is intrusive towards them (e.g., interrupts conversations, games or activities; can start using other people's things without asking or receiving permission; teenagers and adults can get involved or take over what others do).
B) The symptoms of inattention or hyperactivityimpulsiveness must have been present before the age of 12 years.
C) The different symptoms of inattention or hyperactivity must occur in at least two contexts such as at home, school or work, with friends or relatives or in other activities.
D) The symptoms must also interfere with the quality of social, school or work functioning.
E) The presence of a psychotic and/or mental disorder that can better justify the presence of symptoms is excluded. DSM-5 [27] also lists other disorders related to emotional dysfunctionality, but this time with respect to attachment theory (attachment disorders), referring to the disturbed and/ or inadequate social relational mode, and are more related to disorders caused by traumatic and stressful events:

1) Reactive attachment disorder
Two forms are known

a)
Inhibited type: the subject has diffi culty in engaging in interpersonal relationships and responding adequately to them according to the level of development; there is excessive inhibition, hypervigilance and a contradictory attitude towards the caregiver. The inhibited type is characterised by the absence of organised attachment behaviour, low social involvement, diffi culty in emotional regulation, hypervigilance, inexplicable fear and outbursts of anger; Citation: Perrotta

3)Attachment disorder interrupted
In the child it presents itself as the effect of traumatic separation from the attachment fi gure (parents or caregivers), frequent separation episodes or the psychological impact of grief following the death of the caregiver. The child with interrupted attachment disorder displays an insecure-disorganised behavioural pattern, i.e. highly dysfunctional with respect to the objective of attachment, which is to ensure the closeness and protection of the mother and/or caregiver. This pathological behavioural model of the child can be found in the interaction with attachment fi gures, in conjunction with stressful life situations or separations. The child, in such contexts, shows behaviours that express great confusion and internal contradictions with respect to the relationship with the caregiver: for example, looking elsewhere while the mother takes him in her arms or while he tries to reach her, agitation, rigidity. Interrupted attachment disorder in the child expresses a global disturbance of the child's feeling of security and protection and develops within seriously dysfunctional relationships, in which the primary function of the attachment system is altered (that the child may experience a sense of internal security).

The etiopathological and neurobiological profi les
The origins of behavioural disorders may be of a different nature. In fact, there are many risk factors that contribute to defi ning a behavioural regulation problem. Among them, there are:

d)
Risk factors related to prenatal (exposure to toxins during pregnancy) and perinatal (poor quality of care immediately after childbirth) [30].

e)
Coercive parental educational style and insecure or disorganised attachment style between child and reference adult [36].
f) Continuous confl icts within the family context, with exposure to violent acts, mistreatment or situations of abuse, which have exposed children to rejection or abandonment, have suffered excessively strict and frustrating discipline, early departure from the family nest, have suffered from organic diseases of some importance without having parents or adults attentive and understanding towards them, inconsistent or excessively permissive parental attitudes [37]. All these circumstances are capable of negatively affecting the child's future ability to have a solid and robust reality plan and a functional use of defence mechanisms [38,39].
Nevertheless, it is not uncommon to witness conditions that are associated with behavioural disorders, especially in adulthood and with the evolution of these morbid conditions into real personality disorders [41,42], such as anxiety disorders [43] and panic disorders [44], post-traumatic stress [45,46], sleep disorders [47], depressive disorders [48] and suicidal risk [49], to be treated in psychotherapy [50] with possible pharmacological support.

Treatments and therapy
Children and adolescents with conduct disorders represent a large group of subjects with different characteristics in terms of: type of disorder, intensity, course, evolution and prognosis.
Several authors also point out that aggressive and antisocial behaviour has a multifactorial etiopathogenesis associated with characteristics of the individual, family, peer group, school and socio-cultural context [51,52]. abusing behaviour without having the possibility of developing more adaptive ones [52]. In general, individual behavioural therapies [53][54][55], have the common objective of supporting the child in: recognising stimuli related to aggression and antisocial behaviour, modifying cognitive distortions, improving problem-solving skills and dealing with aggression and frustration. Therapies, therefore, focus on modifying the child's abilities in each of these areas [51,56]. In detail, the therapist, after identifying the problem-solving situation with the minor, supports him/her in generating different types of solutions and evaluating the positive or negative consequences of the behaviour, thus increasing his/her predictive capacity [55]. The main techniques used are: modeling exercises, role playing, reinforcement programmes such as token economy.
Moreover, according to some authors [57], it is evident how the interspecies interaction typical of Assisted Interventions acquiring better strategies for self-control, they will have more tools to resolve confl ict situations in a more appropriate way.
Moreover, it is foreseen the use of behavioural contracts (called "goals") in which minimum school objectives are set, agreed during the meetings with teachers, where the achievement of these is associated with a bonus system. Training on minors takes place by creating situations of "structured provocation" where members of the group act as emotional activators. In these controlled situations, the child directly experiences self-control exercises in order to increase the use of these techniques for anger management. The main tools used in the interaction of the class group is role-playing.

Conclusions
In conclusion, it emerges that disruptive behaviour, impulse control and conduct disorders have two important critical elements to take into account. The fi rst is that these disorders, having a multi-dimensional etiology: the biological factor, the minor, the family and the social context, the interventions require a high level of complexity. The second data is that these disorders, often evolving into more complex personality disorders, such as the antisocial personality disorder, make it even more diffi cult to establish a good level of compliance, thus reducing the possibility of a positive resolution of the problem [67]. It is clear how these characteristics can signifi cantly decrease the level of positive prognosis with a poor response to treatment. Different studies [51,68] show how multimodal interventions, embracing the different dimensions of the problem, can increase their level of effectiveness. In our opinion, even multimodal interventions have two important limits: the fi rst is a high social cost and the second is that these interventions often deal with secondary or tertiary prevention, i.e. to intervene on subjects who already present problems. We understand that the time factor can play a fundamental role to treat these pathologies and have a positive resolution. On the basis of this evidence, in our modest opinion, it would be appropriate to highlight a series of predictive behaviours in children that can make it possible to anticipate a diagnosis of behavioural disorders, so as to intervene at an early stage and prevent them from developing into more serious personality disorders. In Italy, ISTAT, through research conducted annually in primary and secondary schools, has found that among the disorders present in school, mental disorders account for 73%, of which 31.1% are attention and behaviour disorders [69]. These worrying data indicate an important increase in mental discomfort for children aged 6 to 12 years. Furthermore, studies conducted in the USA [70][71][72] have shown that in the prison population, the requirements for attention and behaviour disorders are often met. Therefore, understanding how these types of disorders can increase the likelihood of criminal activity in adulthood, our hypothesis is, that it may be desirable to increase the number of multi-modal primary prevention interventions aimed at families [73] and children between 6 and 12 years of age. This is because, in our opinion, they could nip the phenomenon in the bud, or at least reduce the population of those who may subsequently develop behavioural problems. If the hypothesis were confi rmed, the costs of secondary and tertiary interventions would also be reduced. Moreover, the hypothesis of primary prevention interventions at an early age could increase the level of positive prognosis precisely because there would be no evolution in more complex diagnoses. In addition, the child would be prevented from encountering legal measures. Moreover, on the basis of what has been observed, it could be hypothesized that the spread of primary prevention programmes could considerably reduce: the use of drugs and the development of "criminal attitudes" [74][75][76][77], inevitably leading to a reduction in the resulting social cost, but this hypothesis should also be verifi ed with systematic studies on these subjects.