Transcranial Direct Current Stimulation in Treatment of Child Neuropsychiatric Disorders: Ethical Considerations

Abstract

Transcranial direct current stimulation (tDCS) is a noninvasive electrical stimulation performed using low electric currents passing through two electrodes. The provided current passes from the anode to the cathode and induces electric fields in the surface neurons. It then modulates synaptic plasticity and finally changes cortical excitability or improves clinical outcomes, which outlast after a duration of stimulation. Meta-analyses have supported the beneficial effects of tDCS treatments in child neuropsychiatric disorders. However, the study of vulnerable children remains controversial and is a great deal for ethical considerations. Because the developing brain has some important physiological differences from the matured brain, specifically less γ-aminobutyric acid (GABA)ergic inhibition and more myelination, the opportunity to modify neurological disorders to be close to the normal level in childhood after tDCS is likely to be higher than in adults. In contrast, these physiological differences may result in unexpected excitability in children's brains and were criticized to have an unsafe effect, specifically seizures, which is a serious adverse events. As mentioned above, using tDCS in children appears to be a double-edged sword and should be ethically considered prior to wide use. Assessing between benefits of tDCS treatment within the golden period of brain development and the risk of seizure provocation is important. Thus, this perspective article is aimed to exhibit broad concepts about the developing brain, tDCS in children, pathophysiology of neuropsychiatric disorders and tDCS beneficence, tDCS safety and tolerability in children, and missing good opportunities or taking risks in tDCS.

The use of noninvasive brain stimulation techniques in autism spectrum disorder

“…The current modulates the electrical field impacting surface neurons, increasing or decreasing the probability of neuronal firing in the affected area. Anodal stimulation depolarizes neurons leading to an increase in the likelihood of firing and cathodal stimulation hyperpolarizes neurons decreasing the likelihood of firing (Auvichayapat & Auvichayapat, 2022; Ciechanski & Kirton, 2017; Moreno‐Duarte et al, 2014; Woods et al, 2016).…”

“…Anodal stimulation places the anode over the ROI and the cathode at a distant or “inert” location; cathodal stimulation reverses this paradigm. In bihemispheric stimulation both electrodes are placed on ROIs, the anode over the ROI one is seeking to depolarize and the cathode over the location one is seeking to hyperpolarize (Auvichayapat & Auvichayapat, 2022; Ciechanski & Kirton, 2017; Moreno‐Duarte et al, 2014; Woods et al, 2016). Beyond electrode placement, polarity, and intensity – the individuals' brain state at the time of stimulation is another important factor impacting the effects of tDCS.…”

“…Common reported side effects of tDCS are all considered mild and include sensations (i.e., tingling, itching, and mild burning) and redness at the stimulation site. Uncommon side effects include headaches, nausea, small blistering at the stimulation site, mood changes, difficulty concentrating, and transient changes in attention and memory (Auvichayapat & Auvichayapat, 2022; Buchanan et al, 2021; Zewdie et al, 2020). The largest tDCS safety data set, composed of >2800 tDCS sessions across ~500 children, was aggregated by Bikson and colleagues (Bikson et al, 2016) and found no serious adverse effects and low dropout rates across the studies.…”

On‐Demand Chemomagnetic Modulation of Striatal Neurons Facilitated by Hybrid Magnetic Nanoparticles

“…[ 7 ] Deep brain stimulation (DBS) is the most popular neuromodulation approach, which requires the insertion of a millimeter thick metallic electrode inside the brain to stimulate specific neurons in the deep brain region, [ 8 ] and an implantable pulse generator device. [ 9 ] Regardless of the high therapeutic efficacy, DBS remains to be highly invasive and has a number of risks associated with surgery complications [ 10 ] and hardware difficulties. [ 11,12 ] Other technologies have been developed to mitigate the invasiveness of electrode‐based DBS, as are transcranial repetitive magnetic stimulation (rTMS), [ 13 ] transcranial direct current stimulation (tDCS), [ 14 ] and transcranial focused ultrasound stimulation (tFUS).…”

“…[11,12] Other technologies have been developed to mitigate the invasiveness of electrode-based DBS, as are transcranial repetitive magnetic stimulation (rTMS), [13] transcranial direct current stimulation (tDCS), [14] and transcranial focused ultrasound stimulation (tFUS). [15] Regardless of the nature of the current or pulses applied, these minimally invasive therapies suffer from a broad radius of action on the order of millimeters to centimeters [10,16,17] High spatial resolution is offered by cell-type specific neuromodulation technologies such as optogenetics, [18] designer receptors exclusively activated by designer drugs (DREADDs), [19] and emerging nanotechnologybased neuromodulation. Optogenetics has become one of the most popular technologies in neuroscience as it offers high spatiotemporal resolution.…”