According to the Center for Disease Control (CDC), attention deficit hyperactivity disorder (ADHD) and autism spectrum disorder have become more prevalent in our society over the last 60 years. It was not until the 1960s that the American Psychiatry Association classified ADHD as a mental disorder. In 1980, it was referred to as “attention deficit disorder with or without hyperactivity”. According to a 2016 report by the CDC, 6.1 million children between the ages of 2 - 17 are affected. Furthermore, children with ADHD showed significant behavioral or conduct problems. Moreover, 3 in 10 children with ADHD also have anxiety.

A complete understanding of the causes of ADHD is not currently available [1]. It is known that some cases of ADHD can be inherited, and having blood relatives, such as a parent or sibling, with ADHD or another mental health disorder is a risk factor. Exposure to environmental toxins, such as the lead found mainly in paint and pipes in older buildings could play a part. Maternal drug use, alcohol use, or smoking during pregnancy are also risk factors [2].

While there is no known specific cause for ADHD, variations in neurotransmitter levels, such as dopamine, norepinephrine, and serotonin in the brain can contribute to the severity of the symptoms [3]. For example, because dopamine helps a person to focus and rewards the brain for completing tasks, the presence of lower dopamine levels in the brain means a person might have trouble maintaining focus on a task, or seeing it through to the end. It has been suggested that persons with ADHD have more dopamine transporter proteins due to genetic variations, which work to remove dopamine from the brain. If there are too many dopamine transporters in the brain, too much dopamine is being removed too quickly. It has also been proposed that ADHD is associated with changes in functional connectivity in resting state networks of the brain [4]. These networks could include the default mode network, as well as visual, sensory motor, attentional, frontal, central executive, and frontal networks. This is particularly relevant in the present case, because it has been shown that transcranial LLLT can produce beneficial modifications in the default mode network in patients suffering from chronic traumatic brain injury [5] and chronic stroke with aphasia [6].

Treatment of ADHD has generally involved pharmacological administration of stimulants, such as methylphenidate (Ritalin) or amphetamine (Adderall) [7]. However, in 2018 a study was published in the journal Pharmacy [8] which concluded “Results revealed that Adderall had minimal, but mixed, effects on cognitive processes relevant to neurocognitive enhancement (small effects), and substantial effects on autonomic responses, subjective drug experiences, and positive states of activated emotion (large effects). Overall, the present findings indicate dissociation between the effects of Adderall on activation and neurocognition, and more importantly, contrary to common belief, Adderall had little impact on neurocognitive performance in healthy college students. Given the pilot design of the study and small sample size, these findings should be interpreted cautiously. The results have implications for future studies and the education of healthy college students and adults who commonly use Adderall to enhance neurocognition”.

The technology is known as Low Level Laser Therapy (LLLT) delivers red and/or near-infrared light from a laser or a LED (light emitting diode) to a particular part of the body. LLLT initiates a process called photobiomodulation, which can in many circumstances provide physiological benefits lasting much longer than the duration of irradiation. LLLT has been widely employed for reducing pain, inflammation, preventing tissue damage, and the stimulation of healing of wounds or other types of injuries [9]. Because LLLT does not involve any drugs or invasive modalities, it is remarkably free of side effects, and has been generally recognized as safe by the FDA.

The first law of photobiology states that a photon must be absorbed by a specific molecular chromophore in order to have any biological effect. The chromophores that have been postulated to be useful in PBM, absorb at different wavelength regions of the electromagnetic spectrum (blue, green, red, NIR), and are shown in Figure 1.

Cytochrome C oxidase (CCO) is the terminal enzyme (unit IV) in the electron transport chain situated in the outer mitochondrial membrane. The electron transport chain, through a series of redox reactions, facilitates the transfer of electrons across the inner membrane of the mitochondria. The net result of these electron transfer steps is to produce a proton gradient across the mitochondrial membrane that drives the activity of ATP synthase (sometimes-called unit V) that produces the high-energy adenosine triphosphate (ATP) from ADP. CCO mediates the transfer of electrons from cytochrome C to molecular oxygen. CCO

is a complex protein, composed of thirteen different polypeptide sub-units, and contains two heme centers and two copper centers. Each of these heme and copper centers can be either oxidized or reduced, giving sixteen different oxidation states. Each of these oxidation states has a slightly different absorption spectrum, but CCO is almost unique amongst biological molecules in having a significant absorption in the near-infrared spectrum.

Regardless of the precise chromophore, all the evidence points to mitochondria playing a major role as the photo acceptors in LLLT and PBM (Figure 1). This is particularly relevant in the present case, because it has been shown that persons who suffer from ADHD also show evidence of mitochondrial dysfunction [10].

In recent years, the application of LLLT to the head for treating many brain disorders and improving cognitive performance has attracted an exponentially increasing level of interest [11] [12]. Brain damage caused by stroke or traumatic brain injury, neurodegenerative diseases (Alzheimer’s and Parkinson’s), psychiatric disorders (depression, anxiety, insomnia, opiate addiction) have all been treated with transcranial LLLT.

Dr. Stephan and Mr. Banas have been using and “pioneering” this LLLT technology in their office for over 15 years, mainly for treating orthopedic injuries and reducing pain and inflammation. However, for the last few years they have started to treat brain disorders, and so far have published three sets of case studies describing the benefits of transcranial LLLT. These comprise a serious case of traumatic brain injury [13], and two sets of cases in patients suffering from dementia and post-traumatic stress disorder [14] [15].

The Theralase® TLC-2000 CLT laser head we used contained five super-pulsed 905 nm diodes (200 nsec pulse duration) each with the ability to put out 200 mW average power, plus four 660 nm diodes each with the ability to put out 100 mW power. Patients were treated on four areas on the forehead over the pre-frontal cortex for two minutes 15 seconds per site. The power settings were 65 mW for the five 905 nm diodes and 65 mW for the four 660 nm laser diodes. The energy delivered per site was 79 J, and the total energy delivered over four sites was 315 J. The patient was put in a supine position and protective eyewear was worn. No discomfort was reported by any patient (Figure 2).

Currently, there are many studies in progress seeking to test the benefits of photobiomodulation in a wide variety of brain disorders. Transcranial LLLT is certainly one of the biggest breakthroughs in therapeutic medicine over the last decade. However, very little has been published regarding the use of LLLT in ADHD. The case studies reported here show that this could be a simple answer to the ADHD issue. The specific mechanisms responsible for the beneficial effects of LLLT may well include improvements in mitochondrial function and increased functional connectivity in the default mode network. However, other beneficial effects including, the reduction of neuroinflammation, increased cerebral blood flow, reduction of oxidative stress, and the stimulation of neuroplasticity and synaptogenesis, could also play a part. The simple and inexpensive procedure of transcranial LLLT suggests that a formal, controlled randomized clinical trial study should be undertaken as soon as possible. Moreover, recognized assessment scales such as the ADHD Rating Scale V for children [16] or the Cognition and Motivation in Everyday Life (CAMEL) Scale [17] should be used to quantify the improvements. At present, we are reaching out to local school systems to make them aware of this breakthrough, which could be administered to affected children at minimal cost and with no side effects.

The authors declare no conflicts of interest regarding the publication of this paper.

Stephan, W., Banas, L.J., Brierley, W. and Hamblin, M.R. (2022) Efficacy of Photobiomodulation for Attention Deficit Hyperactivity Disorder (ADHD): Case Studies. World Journal of Neuroscience, 12, 136-143. https://doi.org/10.4236/wjns.2022.123015