Mechanisms of Action of Noninvasive Brain Stimulation with Weak Non-Constant Current Stimulation Approaches

Abstract

Objective: Non-constant current stimulation (NCCS) is a neuromodulatory method in which weak alternating, pulsed or random currents are delivered to the human head via scalp or earlobe electrodes. This approach is widely used in basic and translational studies. However, the underlying mechanisms of NCCS, which lead to biological and behavioral effects in the brain, remain largely unknown. In this review, we characterize NCCS techniques currently being utilized in neuroscience investigations, including transcranial alternating current stimulation (tACS), transcranial pulsed current stimulation (tPCS), transcranial random noise stimulation (tRNS), and cranial electrotherapy stimulation (CES).
 Method: We unsystematically searched all relevant conference papers, journal articles, chapters, and textbooks on the biological mechanisms of NCCS techniques.
 Results: The fundamental idea of NCCS is that these low-level currents can interact with neuronal activity, modulate neuroplasticity and entrain cortical networks, thus, modifying cognition and behavior. We elucidate the mechanisms of action for each NCCS technique. These techniques may cause microscopic effects (such as affecting ion channels and neurotransmission systems) and macroscopic effects (such as affecting brain oscillations and functional connectivity) on the brain through different mechanisms of action (such as neural entrainment and stochastic resonance).
 Conclusion: The appeal of NCCS is its potential to modulate neuroplasticity noninvasively, along with the ease of use and good tolerability. Promising and interesting evidence has been reported for the capacity of NCCS to affect neural circuits and the behaviors under their control. Today, the challenge is to utilize this advancement optimally. Continuing methodological advancements with NCCS approaches will enable researchers to better understand how NCCS can be utilized for the modulation of nervous system activity and subsequent behaviors, with possible applications to non-clinical and clinical practices.

A Comparison Between Cognitive Assessment and Neurobiology Technology Assessment of Dyslexia: A Literature Review

“…The use of neurobiology technology to assess Dyslexia, however, has the advantage of being easier to judge on a scale, and the bioinformatics can break through the linguistic limitations, and the bioinformatics does not depend on the child's understanding of the test questions to detect the child's risk of Dyslexia before the cognitive test (Carrasco & Carrasco, 2022). In the field of biological neurology, current research on Dyslexia has evolved from focusing on the neocortex of the brain and showing changes in the degree of asymmetry in the temporal plane at the structural level to finding abnormal white matter integrity along the left arcuate fasciculus (Guadalupe et al, 2015, Zhao et al, 2016Bahrami et al, 2021;Vellasamy et al, 2022;Shirehjini et al, 2023). However, within the field of neurobiology, there is no consensus on which neurobiological signals can accurately predict and determine Dyslexia (Norton et al, 2015).…”

Exploring the Correlations Between Game Addiction, Aggression, Narcissism, and Self-Control among Adolescents: A Comprehensive Literature Review

“…In numerous literatures, aggression is typically categorized as physical, such as hitting, kicking, and spitting; verbal, such as shouting, threatening, and saying hurtful words; and relational, such as slandering someone and causing harm to social relationships (Coyne et al, 2010;Zhang et al, 2016;Ettekal & Ladd, 2017). Thereinto, it was found that physical and verbal aggression are regarded as overt aggression (Putallaz et al, 2008;Smith et al, 2009) (see in Figure 1).…”

“…Many scholars have explored that low self-control is linked with aggressive and risky behaviors over time (Pratt et al, 2014;Reisig & Pratt, 2011;Shirehjini et al, 2023). Selfcontrol is found to be inversely related to self-reported aggression (Özdemir et al, 2013), laboratory aggression (Denson et al, 2011), driving aggression (Ellwanger & Pratt, 2014), aggressive ideation and aggressive behavior (Murray et al, 2016), and direct aggression (Meldrum et al, 2018).…”

“…Low self-control linked to aggressive and risky behaviors (Pratt et al, 2014;Reisig & Pratt, 2011;Shirehjini et al, 2023)…”

The Effectiveness of Transcranial Direct Current Stimulation (tDCS) and Omega-3 on Food Craving, Executive Functions, Weight, and Depressive Symptoms in Patients with Depression and Overweight: A Randomized Controlled Trial

“…Through tDCS, a low-intensity current of often less than or equal to 2 milliamps (mA) is applied at the scalp level ( 17 ). However, it is important to note that only a fraction of this current, estimated in the order of tens of microamperes, actually reaches the neural system, typically targeting areas like the DLPFC ( 18 , 19 ). Therefore, tDCS is not considered an invasive procedure ( 20 ).…”