INTRODUCTION

Attention deficit hyperactivity disorder (ADHD) is a common, early-onset, life-long neurodevelopmental disorder that has been recognized by the Diagnostic and Statistical Manual of Mental Disorders (DSM-5) (Posner et al., 2021). The global prevalence of ADHD in children is said to be around 5%, with a male-to-female ratio of 4:1, however, this varies in different countries (Nice, 2022; Kanbayashi, 2003).. An additional 5% of children have pre-clinical ADHD, where key symptoms that define ADHD are present, but not significant enough for a diagnosis (Sayal et al., 2018). 

ADHD is generally divided into three sub-types, depending on the symptoms presented (Willcutt et al., 2012). Those with a predominantly inattentive presentation have the symptoms relating to a deficit in attention, but not hyperactivity or impulsivity, while those with a predominantly hyperactive-impulsive presentation have the opposite. Meanwhile, those with the third subtype are impulsive, hyperactive, and inattentive (Rowland et al., 2008).

Common examples of inattention include a lack of focus on details (and therefore careless mistakes), difficulties maintaining attention, difficulties listening when spoken to directly, difficulties completing tasks (leading to organisational issues), and reluctance to participate in tasks which require sustained focus and effort. Those who struggle with attention may also lose items, be easily distracted and forgetful (Williams, 2017). Someone who is hyperactive may fidget, struggle to sit still for a long period of time, run around and/or climb (even when it is not socially acceptable to do so), and talk excessively (Cleveland Clinic, 2017). Meanwhile, if someone struggles with impulsivity, they may respond to questions before someone has finished, interrupt others when speaking and/or struggle to wait for their own turn (Substance Abuse and Mental Health Services Administration, 2018).

For diagnosis by a medical professional, six symptoms must be present for longer than six months. Additionally, as with most conditions defined in the DSM-5, symptoms must not be able to be explained with a different disorder, must not only be present during a schizophrenic episode, must have been present prior to a certain age (in this case, twelve), and must cause problems in day-to-day life in more than two settings (Substance Abuse and Mental Health Services Administration, 2018). 

There are many treatment plans to combat these symptoms including pharmaceutical agents and psychotherapeutic interventions, both of which have demonstrated strong therapeutic responses (Rivas-Vazquez et al., 2023). Medication-based treatment for ADHD includes stimulants such as amphetamines and methylphenidate and non-stimulants such as Atomoxetine (Faraone, 2021; Ledbetter, 2006). 

The prevalence of ADHD has been increasing over time, especially with late diagnosis,  as will be discussed in the paper. Many researchers believe this is because previously under-recognised groups (such as adolescents and women) are now being diagnosed. The most likely reason for the original underdiagnosis is that females tend to present as predominantly inattentive and are ‘less likely to have learning difficulties or manifest problems’, leaving their struggles unnoticed and therefore undiagnosed (Mowlem et al., 2018). Meanwhile, others say over-diagnosis is occurring; it could be argued that the overall decreasing attention spans may increase misdiagnosis in this field, which will be discussed in this paper (Kazda et al., 2021). 

 

DIAGNOSTICS AND CAUSES

Societal/Diagnostic/Genetic contributors 

The Impact of the Environment 

Even though genetics is seen as the main contributor to ADHD, some psychosocial factors may also alter the neurobiology of the brain and consequently participate in causing ADHD (Thapar et al., 2013). Adverse childhood experience (ACE), or video gaming are under the scope of scientific studies to determine whether they can be considered as the main contributors to the neurodevelopmental disorder (Zarei et al., 2021). Adverse childhood experiences refer to abnormal and distressing events a child under eighteen has to suffer repeatedly throughout his childhood (Herzog et al., 2018). These hurtful events, such as neglect and abuse, are the reflection of a dysfunctional environment. These experiences can lead to trauma for the individual who may go through mental challenges in their later life as a result (Tzouvara et al., 2023). Studies conducted to analyse the impact of such experiences among young populations unveiled that children who experienced adverse events during their childhood are more likely to develop moderate to severe ADHD (Alfonso et al., 2023). Further studies demonstrated the consequences of stress on the human brain and the impact on neuronal pathways, which is likely to be at the origin of a child’s hyperactivity (Gody, 2018). Although the association between ACE and ADHD is underlined in several studies, not enough evidence has been provided to prove that ACE is a direct contributor to ADHD and it is important to note that not all the children experiencing abuse in their childhood suffer from ADHD (Schwartz, 2023). ACE is an underlying factor of ADHD, where abuse and neglect are recurrent factors of children diagnosed with this neurodevelopmental disorder (Posner, 2020).

 

The Impact of Video Games on ADHD

Additionally, a new category of disorder, listed in the ICD-11 (International Classification of Disease by the World Health Organization) emerged as a consequence of the prevalence of patients suffering from mild to severe addiction. This includes all addictive disorders, such as dependence on video games ​​(www.who.int, n.d.). The general concern about the addiction to video games for children and teenagers raised the question of it being a factor contributing to ADHD. A recent meta-analysis confirmed that children suffering from ADHD are more likely to develop an addiction to video games (Koncz, 2023). However, there is not enough evidence to conclude that video gaming is a contributing factor to ADHD. Video gaming disorder, like all addictive disorders, triggers mental health issues, but not exclusively or especially ADHD as far as current research is concerned (Garcia, 2020). Generally, societal contributors worsen the condition of the patient suffering from ADHD, or act as an associated factor to the main condition of the patient, but are not enough to diagnose ADHD, which remains a polygenic disorder (Ginsberg et al., 2014). 

 

Diagnosing ADHD

As a neurodevelopmental disorder, ADHD is mainly diagnosed during the primary years of school (CDC, 2023). The increasing number of diagnoses gave rise to a recent analysis mentioning the overdiagnosis of ADHD, especially for young patients with milder symptoms (Kazda, 2021). Boys often show hyperactivity as a symptom, and for this reason tend to be more easily diagnosed than girls who tend to present different and more complex symptoms, such as lack of attention, anxiety or depression (Skogli, 2013).

 

Neurobiology of ADHD 

An Overview of Attentional Resources

As seen above, ADHD is a highly heritable neurobehavioural disorder caused by attentional control impairments (Curatolo et al., 2009). Studies have found that although all humans have an executive attention network with similar anatomy, distinct individual differences in the efficiency of such networks exist (Purper-Ouakil et al., 2011). The heritability of the efficiency of the executive attention network has been discovered through twin studies (SV. Faraone, 2019).

The neuroanatomy of human cognition allows us to decouple external stimuli through inhibition. Such can be defined as the three following distinct capacities including the ability to: inhibit the urge to respond to an event, to interrupt an ongoing behaviour and to protect frontal lobes from interference (Coutinho et al., 2018). All three of these abilities are impaired in individuals with ADHD. MRI studies comparing ADHD patients with control patients revealed that individuals with ADHD have structural dysfunctions of the frontoparietal part of the brain as well as functional impairment (Yu et al., 2023). 

As such, the inattention in ADHD is not caused by a lack of ability to perceive external stimuli, but rather by an inhibition failure to prioritise accordingly (Bédard et al., 2010). Via attentional mechanisms, neurotypical individuals select a limited amount of sensory information to process and neglect the remaining input. This idea is known as Attentional resources (AR), and the theory states that the cognitive system has a limited resource of attention that can be used at once (Oberauer, 2019), while the attentional capacity can change size according to task demands (Young et al., 2002). As such, the performance decrements associated with mental underload can be explained by a lack of appropriate attentional resources. The cases of underload are much more prevalent in ADHD patients. In the Stroop and the shifting attention tests, ADHD patients proved to be inefficient in allocating their AR, increasing distractibility and resorting to more context switching – moving between unrelated tasks in search of stimulation, decreasing sustained attention (Sarter and Paolone, 2011). 

 

Sustained Attention

Sustained attention differs from other areas of attention in that it requires individuals to sustain focus on one or more sources of information for a comparatively extended and uninterrupted duration (Van Zomeren & Brouwer, 1994). According to an experiment conducted by Tucha et al. (2017), patients with ADHD showed significant deficits of medium size in selective attention and divided attention. Medium sustained attention deficits were also observed in measures of alertness. Studies have found that people with ADHD have weaker function and structure of prefrontal cortex (PFC) circuits. The PFC plays an important role in regulating attention, emotion and behaviour (Arnsten, 2009). It has been found that the circuits are especially weaker in the right hemisphere, which specialises in behavioural inhibition. For the PFC to function properly, the correct neurochemical environment is needed. ADHD is associated with genetic changes that weaken catecholamine signalling as well as with slowed PFC maturation in some cases (Arnsten, 2010). As such, individuals with ADHD struggle with maintaining sustained attention.

 

Processing Deficiencies 

Individuals with ADHD also demonstrate deficiencies in both bottom-up and top-down processing. Bottom-up processing initiates by extracting sensory information from the external environment to construct perceptions solely based on the current input of sensory data. This requires no prior learning, and perceptions are exclusively formed based on novel stimuli present in the current external environment (Gibson, 1972). Top-down processing interprets incoming information by drawing on prior knowledge, experiences, and thus expectations. Therefore, there is a great significance of previous knowledge, experience, and expectations in shaping perceptions about new stimuli (Gregory, 1974). It has long been hypothesised that hypoactive cognitive top-down executive control underlies inattention and impulsivity in ADHD while a hyperactive bottom-up processing system leads individuals with ADHD to be overly sensitive, engaging in heightened processing of both relevant and irrelevant external stimuli and thus leading to an elevated susceptibility to external distractions (Petrovic et al., 2016; Osborne et al., 2023). An experiment conducted by Schneidt et al. (2018) revealed that people with ADHD exhibit enhanced bottom-up processing of distractors in trials with high task difficulty as well as enhanced top-down processing in trials with low task difficulty. These discoveries suggest that distractibility in ADHD stems from deficiencies in top-down as well as bottom-up processing.

 

The Role of Dopamine

There is significant back-and-forth activity occurring in the brain’s reward system, and this activity is under the regulation of the neurotransmitter dopamine (Lewis et al., 2022). There have been several studies that suggest a genetic variation in individuals with ADHD that is associated with deficient functions of the dopamine “brain reward” system. This leads to reward deficiency syndrome (RDS), a hypothesised behavioural subtype of ADHD (Blum et al., 2008). This genetic trait is partly due to the particular form of a gene (DRD2 A1 allele) involved in the expression of dopamine receptors. This allele hinders the typical process of placing dopamine receptors in the brain’s rewarding sites and thus, individuals with this abnormality have an insufficient number of dopamine receptor sites in the brain’s reward centres, which impedes the utilisation of the typical amount of dopamine and consequently leads the brain to reduce the level of dopamine production in this region (Blum et al., 2008). As a result, individuals with ADHD have inadequate dopaminergic activity in brain reward centres, leading them to partake in actions aimed at increasing dopamine function (Ibid, 2008).

 

TREATMENTS 

Pharmacological Treatments 

Difference Between Stimulants and Non-Stimulants

Stimulants and non-stimulants are pharmacological medications used to treat ADHD. They work by increasing the levels of certain neurotransmitters such as dopamine and norepinephrine in the brain (NHS, 2021). 

There are many classes of stimulants but the two most primary forms are immediate and extended-release (Cleveland Clinic, 2022). Immediate-release (short-acting) stimulants normally last up to four hours. After taking a short action stimulant dose, people with ADHD may experience “the crash” or “the rebound effect.” This typically involves sharp decreases in energy levels, severe hunger, and an intense drop in mood or depression. Extended-release or immediate acting (long action) are typically taken once every morning. Some last from six to eight hours, while others last up to 16 hours. ADHD stimulants that last longer often result in fewer crashes and reduce the dosage necessary (NHS, 2021). Extended and immediate stimulants are usually categorised into two classes: methylphenidate or amphetamines (Cleveland Clinic, 2022).

The stimulant Methylphenidate is the most commonly used medicine offered to adults, teenagers, and children over the age of 5 diagnosed with ADHD. This stimulant increases activity in areas of the brain that control attention and behaviour by blocking the reuptake of the neurotransmitters norepinephrine and dopamine in presynaptic neurons. By inhibiting transporters, the concentration of dopamine and norepinephrine increases, thus creating a stimulant effect within the central nervous system (Verghese & Abdijadid, 2020). For adults and paediatric patients diagnosed with ADHD for six years or longer, methylphenidate is administered as immediate-release tablets of 5, 10, and 20 mg, and extended-release tablets of up to 72 mg. Children usually take slow-release methylphenidate once a day or standard tablets and capsules up to three times a day. The starting dose for tablets is 18 mg and the same for capsules is 10 mg. There are some adverse side effects in patients using methylphenidate such as insomnia, dizziness, headache, restlessness, decreased appetite, weight loss, and abdominal pain. Patients are also more prone to feeling aggressive, easily agitated, irritable, depressed, anxious, and tense (Faraone, 2018). 

Amphetamines belong to another category of stimulants that increase norepinephrine and dopamine concentrations in the synapse. There are different types of amphetamines used for the treatment of adults with ADHD such as lisdexamfetamine, dexamphetamine, and mixed amphetamine salts (Castells, Blanco, & Cunill, 2018). In the liver, amphetamines metabolise with half lives of ten to fifteen hours, lisdexamfetamine with half lives of 0.6 hours, and dexamphetamine with half lives of around twelve hours (Faraone, 2018). They are usually administered once or twice a day depending on whether they are of immediate or extended release. When the stimulants act on the dopamine transporter, the transport direction is inverted, resulting in an increase of dopamine molecules flowing from the presynaptic neuron towards the synapse. In addition, amphetamines inhibit catecholamine metabolism, which is responsible for the body’s flight or fight response through the protein catechol-O-methyltransferase. The increase in dopamine levels and decrease in COMT improve ADHD symptoms. Similar to methylphenidate, common side effects of amphetamines include increases in blood pressure and heart rate, nausea and vomiting, stomachache, insomnia, dizziness, headaches, and irritability (Castells, Blanco, & Cunill, 2018). 

 

Non-Stimulants

As for non-stimulant medication, the most commonly prescribed type is atomoxetine. This drug binds to the release of norepinephrine, classifying it as a norepinephrine reuptake inhibitor (Mechler et al., 2021). Norepinephrine is the primary neurotransmitter stimulating the body’s fight-or-flight response (Cleveland Clinic, 2022). Atomoxetine stimulates the prefrontal cortex, which is the part of the brain that regulates thought, behaviour, and emotions, which in turn helps people with ADHD reduce their hyperactivity and impulsiveness (Miller, 2023). 

While non-stimulants, including atomoxetine, help treat ADHD, their efficiency is remarkably lower than stimulants and are generally considered as a second option for treatment (Magnus et al., 2023; Mechler et al., 2021). The reasons why non-stimulants are used despite their reduced qualities are either because stimulants were not effective, due to the side-effects of the, or comorbidities in which the stimulant can induce harmful effects and many other reasons (Miller, 2023).

 

The Controversy Surrounding Stimulants

However, another reason why a psychiatrist may prefer to prescribe non-stimulants over stimulants could be because of the concern about a potential link and causation between stimulants and substance abuse in adulthood (Volkow and Swanson, 2008). The reasoning for this is that many stimulant medications and drugs of abuse can increase the dopamine concentration in the nucleus accumbens, which Fernández-Espejo (2000) describes as ‘the neural interface between motivation and action’. Another reason for this concern is that studies have shown that people who are introduced to drugs with the potential of abuse at an early age are at a higher risk for drug abuse in the future (Volkow & Swanson, 2008). 

While substance use can certainly be an issue, it is essential to mention that research disproves the supposed high chances of substance abuse related to all individuals with ADHD using stimulant treatments. After a study made by Chang et al. (2013), the data revealed that there was no indication of an increased risk of substance abuse and that, instead, it had a protective effect against it.

 

Behavioural and Other Treatments 

Cognitive Behavioural Therapy

When treating ADHD, many non-pharmacological therapies can reduce symptoms and difficulties that individuals with ADHD face. A common type of talking therapy is cognitive behavioural therapy (CBT), a counselling course that works on breaking down problems into manageable parts in order to resolve them. Some stages of CBT include cognitive modification, where they replace negative thoughts with more favourable ones. Behavioural modification is another aspect which involves eliminating undesirable behaviours and replacing them with positive ones (Jones, 2022). In regards to effectiveness, a 2016 study found that the use of CBT in conjunction with medication resulted in a greater reduction of ADHD symptoms than medication alone (Charksova et al, 2016; Sprich, 2016). For some CBT may be preferable due to the side effects caused by medications. 

Mindfulness-based cognitive therapy (MBCT) is an alternative treatment which mainly involves meditation. The aim is to pay more attention to your thoughts and become aware of the present moment (Schimelpfening, 2023). This process is helpful in improving many ADHD symptoms such as reducing mind-wandering, distractions and allowing emotion regulation (Bachmann et al, 2016). Combining CBT and MBCT is proven to be useful as it allows the individual to both understand their feelings and learn how to correct thought processes (Schimelpfening, 2023).

 

Occupational Therapy and School Adjustments 

Under the Equality Act 2010, schools are required to adapt and make reasonable changes to ensure individuals with learning disabilities (such as ADHD) have the same opportunities as everyone else. Examples of this include extra time in exams, behavioural interventions, providing a reader and allowing breaks during classes to maintain focus (Akins, nd). Supported by special education needs (SEN), they require that children should be assessed in order to provide the correct support and make necessary adjustments . Additionally, an emotional literacy support assistant (ELSA) may be provided for children who face emotional or social challenges in school. It works by building relationships with the child, talking about difficulties and developing coping strategies. Russell and Mann (2011) found that with one-to-one interventions, children’s emotional literacy noticeably improved (Woodcock et al, 2019).

Similarly, in the UK there are legal obligations for employers to make work environment adjustments and provide support to employees with ADHD and other health conditions. This includes a change in the workspace to avoid distractions, adjusting work hours and individual coaching to develop strategies (Lauder, 2021). This ensures they aren’t disadvantaged and minimises any challenges they may face.

 

Music Therapy

Music therapy (MT) is a method of reducing stress and improving mental health that involves playing and/or listening to music (Wang & Agius, 2018). In more recent years, MT has started to be used as a treatment for those with ADHD. One study found that the frequency of maladaptive, unpleasant behaviours associated with ADHD was reduced after MT, as well as noting that there were increases in generally positive behaviours and attributes, such as creativity (Zhang et al., 2017). It can also be used to treat conditions such as anxiety and depression, which often coexist with ADHD, or even occur due to the stress of ADHD (Wang & Agius, 2018). There are fairly high comorbidity rates of 15-35% (anxiety) and 12-50% (depression), showing that MT could be beneficial in multiple ways as it also reduces these comorbid conditions (Gnanavel et al., 2019). A study by Park (2023) looked at its effectiveness from a neurobiological standpoint and found that serotonin was increased with MT. Music has also been shown to increase levels of dopamine and oxytocin (Speranza et al., 2022). Dopamine triggers the reward centre, increases memory and helps with attention (Klein et al., 2018), all of which are beneficial for people with ADHD.

 

Transcranial Direct Current Stimulation (tDCS) 

Transcranial direct current stimulation (tDCS) is a non-invasive brain stimulation technique that is being used to regulate cortical excitability (Thair et al., 2017). It involves the placement of electrodes on the scalp so that a low-intensity current can be delivered to the desired part of the brain (Venkatasubramanian, Sreeraj & Arumugham, 2023). This form of neuromodulation was approved by NICE (2015), but has not yet been approved by the Food and Drug Administration. Although there are some who are more hesitant due to side effects such as dizziness and headaches, the majority of studies agree that tDCS is both safe and effective (Bikson et al., 2016; Arul-Anandam, Loo & Sachdev, 2009).

Neurologists are currently investigating how tDCS can be used in the treatment of multiple conditions including depression, autism, dyslexia (which all have high comorbidity with ADHD) and ADHD itself (Salehinejad et al., 2022). One study found that attention in those with ADHD could be increased with tDCS, but only at certain current intensities, while 64.7% of studies that were analysed in Salhinejad’s systematic review found an improvement in at least one variable (Breitling-Ziegler et al., 2021; Salehinejad et al., 2022). Although more research will have to be done, it is clear that tDCS has the potential to treat ADHD.

 

DISCUSSION 

ADHD has been shown to be a polygenic, highly heritable disorder, but also a disorder that can be linked with both societal and environmental factors. On the biological side of explanations, research has shown that genes play a part in ADHD, as many people with ADHD also have children, siblings and/or parents with the disorder too. In more recent years, with technological advancements, doctors have been able to create a genetic history of those with ADHD and look at the patterns of inheritance within families. This has expanded our knowledge of the inheritability of the condition, as well as the biology behind it. However, there are also other factors that are said to be linked with ADHD. For example, many individuals with the condition were exposed to alcohol, tobacco and other substances in utero, suggesting that these could play a part in the development of the disorder. Others have linked ACEs with ADHD, as studies have found that children are more likely to develop ADHD if they have had a highly stressful and/or traumatic childhood. Additionally, some research has investigated how exposure to technology interacts with ADHD. As our society becomes increasingly tech-dependent and many teenagers start to demonstrate symptoms of screen addiction, it is more crucial now than ever to recognise and raise awareness of the relationship between excessive screen dependency and neurodevelopmental disorders. Beyond the symptoms of ADHD, such acknowledgement could have a broader positive implication on our overall mental health, meaning that the stress, anxiety and depression that can often come with ADHD can also be reduced. 

Until now we have touched upon how ADHD seems to come in a package with impaired cognitive development, yet the question stands stronger than ever in an age of lowering attention spans: is ADHD a cognitive deficit or simply a cognitive difference? The scope of this disorder is larger than we see as a society and more obscure than we’d like to think as individuals, and as such to fabricate an effective treatment, we must first consider whether ADHD is a malevolent herb that must be treated rather than a variation in cognitive development.

There are many treatments that can be used to treat ADHD’s symptoms, including pharmacological drugs and multiple forms of therapy. Traditionally, stimulants have been prescribed as the first line of treatment against ADHD, which is a problem for three main reasons. The first is that stimulants often create undesirable side effects that can end up lowering someone’s quality of life more than the condition that the drugs are trying to decrease. Secondly, these drugs do not work on everyone. This is especially significant as it is not the individual’s fault if stimulants do not work for them, and yet their next best choice is something less effective. Researchers and medical professionals should work on developing non-stimulants to improve their effectiveness so that those with ADHD don’t have to be forced to make a decision between uncomfortable side effects and a lack of efficacy. Finally, patients may have their own views about how they want to be treated. For example, patients may prefer therapy over medication due to side effects (such as insomnia, headaches, fatigue, decreased appetite, weight loss, and abdominal pain) and cost. Doctors have a legal, binding duty to listen to their patients and inform them well enough to make their own decisions and choose which treatment path is right for them, but this is unfortunately not always the case. In some cases, someone may only be seeking out a diagnosis for their condition, not treatment. Recently, there has been an increase in disability pride, meaning that many people are choosing to embrace their neurodivergence, celebrate their symptoms and be themselves, instead of “masking” and trying to eliminate their disorder with intensive therapies and/or medication that can have side-effects. Although there are still many who desire treatment, it is possible that, in the future, there may be a shift in focus away from CBT, tDCS and medication, and towards improving the facilities in schools, homes and workplaces to better accommodate those with the disorder, instead of forcing them to change who they are. 

 

CONCLUSION 

Exploring the neurobiology of attention, ADHD emerges as a highly heritable disorder with impairments in attentional control. Neuroanatomy reveals structural and thus functional dysfunctions in the parietal region of ADHD individuals. Attentional resources play a crucial role, with ADHD individuals exhibiting inefficiencies in sustaining attention. Sustained attention deficits are linked to weaker prefrontal cortex circuits. Processing deficiencies in both bottom-up and top-down processing contribute to distractibility in ADHD, as they are more susceptible to external distractions. The role of dopamine is also highlighted, suggesting a genetic variation associated with deficient functions in the brain’s reward system, leading to reward deficiency syndrome in individuals with ADHD. 

Regarding treatments, there are two options that are predominantly being used- pharmacological and behavioural. From the pharmacological side, non-stimulants are considered to be a second option to stimulants, as they tend to be less efficient. This is because stimulants have a quicker onset of action and higher response rate, ultimately leading to improving executive functions more effectively. Medical professionals may consider this unfortunate, as stimulants typically bring unpleasant side effects and allegedly make individuals with ADHD more prone to substance abuse. However, the latter has been proven false by studies that demonstrate how stimulants actually make them less prone to substance abuse. With regard to behavioural treatments, talking therapy is a common choice. During CBT therapists will help ADHD individuals to analyse their problems and find ways to cope with them. A study found CBT with medication was more effective than just medication alone. Alternatively, mindfulness-based treatments such as meditation improve focus on tasks and reduce mind wandering. Furthermore, schools and employers are required to make adjustments to help with the struggles people with ADHD may face. This includes regular breaks, one-to-one interventions and adjusting work hours. Subsequently, music therapy is another non-pharmacological treatment that has been shown to decrease both the symptoms of ADHD, and ease the stress that the condition comes with, thanks to the increase in dopamine, serotonin and oxytocin that music induces. Meanwhile, tDCS still needs some adjustment to work for more people, but results suggest that, in the future, it has the potential to be an effective, safe way of treating ADHD.

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