Enhancing focus

Can neurostimulation reliably enhance your focus in day-to-day activities?

Focus is about giving your full concentration to that one thing while saying no to all those things vying your attention. There is no shortage of distraction in this world, so to increase focus levels, there has been a significant interest in the techniques that can do so including transcranial electrical stimulation (tES).

Attentional disturbances lie at the core of many neurological and psychiatric disorders such as ADHD. That is why focus has primarily been taken into account for cognitive enhancement techniques that include video games, pharmacological stimulants and meditational training. The discovery of transcranial electrical current is another technique to the arsenal. It comprises of a weak current that is made to run through two electrodes placed on the skull that changes the excitability of the brain tissues under the electrodes.

A number of studies have been carried out that paired tasks that required focus and attention, with tES (mostly with transcranial direct current stimulation). We will discuss three important aspects of focus and attention here that have been most broadly been targeted to date.

  • Visual Searching
  • Spatial orientation
  • Sustained Attention

Researchers have reported some very promising effects of tDCS in each of these domains.

Visual Searching

The process of scanning the visual field is a common action which makes it an interesting target for cognitive enhancement. Different studies and experiments were performed to examine the results of transcranial electric current on the visual searching.

Visual search performance is supported by an extensive network of brain areas, centered on the right posterior parietal cortex and frontal eye field. Among an array of distracting objects, participants in visual search tasks had to look for a target item. The faster the reaction time in searching, the more efficient the visual search of the participant. The researchers found that anodal tDCS over the right parietal cortex may speed up visual search, while cathodal stimulation may slow it down.

Moreover, it was also found that learning to discover hidden objects fixed in realistic scenes was greatly intensified by anodal tDCS over the right inferior frontal cortex.

Spatial orientation

Another aspect highly relevant to visual search was spatial orienting. These studies figured out that attention and focus are not symmetrically distributed over the visual field. Most people are exposed to pseudoneglect; they overemphasize features in the left versus the right hemisphere. This happens because the right hemisphere is slightly more active than the left.

Presumably, it was seen that tDCS proved to be very effective in increasing the activity of the left parietal cortex beyond that of the right, and resultantly causing a rightward shift in spatial bias. Similarly, a rightward shift for right cathodal tDCS was observed. It was furthermore observed that a “dual” montage with one electrode on each posterior parietal cortex (anode on left; cathode on right) was even more effective.

Sustained Attention

Typically after prolonged time-on-tasks, the average performance of a person declines which is called vigilance decrement. To find ways to hinder vigilance decrement, different research work was done that examined the effects of tES on sustained attention.

It was reported that the vigilance decrement could be stopped by applying bilateral tDCS to the dorsolateral prefrontal cortex early into a vigilance task.

Furthermore, prefrontal tDCS did not affect performance on a sustained attention to response task, but they did increase mind wandering. In conclusion, two studies reported that prefrontal tDCS specifically offsets the vigilance decrement, suggesting that its effects may only become apparent after prolonged task performance.


With the applications mentioned above, we come to the conclusion that a person’s focus can be enhanced through transcranial electric current stimulation. The effects of tDCS are not confined to the stimulation period, but can outlast it for minutes to hours, or even months after multiple stimulation sessions!



Transcranial Direct Current Stimulation’ May Boost Cognitive Function And Brighten Your Mood. (2013, october 29). Retrieved from Medical Daily: https://www.medicaldaily.com/put-headset-sharpen-your-focus-transcranial-direct-current-stimulation-may-boost-cognitive-function

ATTENTIONAL MODULATION OF VISUAL PROCESSING. (n.d.). Retrieved from Annual Reviews: https://www.annualreviews.org/doi/10.1146/annurev.neuro.26.041002.131039

Enhancement of attention, learning, and memory in healthy adults using transcranial direct current stimulation. (2014, january 15). Retrieved from Science DIrect: https://www.sciencedirect.com/science/article/pii/S1053811913008550?via%3Dihub

Enhancement of object detection with transcranial direct current stimulation is associated with increased attention. (2012, september 10). Retrieved from BMC Neuroscience: https://bmcneurosci.biomedcentral.com/articles/10.1186/1471-2202-13-108#Sec6

Enhancing multiple object tracking performance with noninvasive brain stimulation. (2015, feb 5). Retrieved from Frontiers : https://www.frontiersin.org/articles/10.3389/fnsys.2015.00003/full

Frequency Band-Specific Electrical Brain Stimulation Modulates Cognitive Control Processes. (2015, september 25). Retrieved from PLOS: http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0138984

Increasing propensity to mind-wander with transcranial direct current stimulation. (2015, feb 17). Retrieved from PNAS: http://www.pnas.org/content/112/11/3314

Modulation of attention functions by anodal tDCS on right PPC. (2015, July). Retrieved from Science Direct: https://www.sciencedirect.com/science/article/pii/S0028393215000950?via%3Dihub

Simultaneous tDCS-fMRI Identifies Resting State Networks Correlated with Visual Search Enhancement. (2016, march 7). Retrieved from frontiers: https://www.frontiersin.org/articles/10.3389/fnhum.2016.00072/full

TDCS guided using fMRI significantly accelerates learning to identify concealed objects. (2012, january 2). Retrieved from Science Direct: https://www.sciencedirect.com/science/article/pii/S1053811910014667?via%3Dihub

The effects of tDCS upon sustained visual attention are dependent on cognitive load. (2016, January 8). Retrieved from Science direct: https://www.sciencedirect.com/science/article/pii/S0028393215302207?via%3Dihub

The Truth About Electrical Brain Stimulation. (n.d.). Retrieved from vitals: https://vitals.lifehacker.com/the-truth-about-electrical-brain-stimulation-1822192429

Transcranial Electrical Stimulation as a Tool to Enhance Attention. (2017, march 10). Retrieved from Speinger Link: https://link.springer.com/article/10.1007/s41465-017-0010-y

When Less Is More: Evidence for a Facilitative Cathodal tDCS Effect in Attentional Abilities. (2012, september ). Retrieved from The MIT PressJournals: https://www.mitpressjournals.org/doi/10.1162/jocn_a_00248



Boost your exercise routines with tACS/tDCS

What's the latest research on using tACS while you're exercising?

We are living in a world that is ultracompetitive in professional sports where victory is determined in fraction of seconds and distance. The difference in the potential of two elite athletes differ in fractions of percentages. This is a reason why athletes take ergogenic aids (any kind of aid/ substance that increases their potential and performance levels). Frequently used ergogenic aid includes hypoxic training and multivitamin supplements. Recently, the use of transcranial electric current stimulation to enhance athleticism has gained great importance in academic study.

It has been proposed that the use of tDCS may enhance mental and physical performance in sports. For example, it has been researched that tDCS could reduce the reflex times to auditory, visual and touch stimuli. It has been shown to reduce tremor and enhance complex motor skills and motor learning in athletes.

There are two ways through which brain stimulation could possibly improve mental and physical performance in sports.

Using tDCS before performance which reduces mental and muscle stress levels and resultantly increases focus for a quicker action.

Using tDCS during performance that would help the athletes to learn motor skills in a better way.

Therefore, it is also very important to note that under what conditions and circumstances the tDCS is being utilized.

Cycling Time to Task Failure Test:

An experiment comprising of 12 recreationally “active” participants was carried out (including 8 men and 4 women, aged between 18 to 44). The participants were randomly given cathodal, anodal and sham stimulations. Meanwhile, they were instructed to avoid alcohol, depressants or any strenuous exercise. Both before and after tDCS, partic

ipants’ neuromuscular abilities/ performances were assessed in cycling sessions. It was observed that participants that received anodal stimulation biked longer than those who received sham or cathodal stimulations. The researchers suggested that the better performance might be the result of higher excitability of motor cortex leading to a decrement in effort and increment in endurance.

tDCS has been used to enhance endurance performance but how it achieved this was previously unk

nown and this study has helped identify the mechanisms. It was discovered that stimulating the brain using transcranial direct current stimulation, over the scalp, to stimulate it, increased the activity of the area affiliated with the contraction of muscles. This decreased perception of effort and increased the length of time participants could cycle for. The team explained that this is because the exercise felt less effortful following stimulation. 

The studies demonstrate that tDCS with the anode over both motor cortices using a bilateral extracephalic reference improves endurance performance. In addition, tDCS can enhance motor learning thereby increasing the benefit of practice and promoting better performance.

Another neur

ostimulation device, called Halo sport that leverages tDCS technology is becoming famous among Olympic, MLB and NLF athletes etc. The device looks like headphones and promises strength, speed, skill and endurance enhancement. The procedure is that you turn the system on for 20 or more minutes, and shortly after that, you are primed neurologically for enhanced learning and performance. The company is the first to offer it commercially to athletes.



Brain doping’ may improve athletes’ performance. (2016, march 11). Retrieved from nature: https://www.nature.com/news/brain-doping-may-improve-athletes-performance-1.19534

Bilateral extracephalic transcranial direct current stimulation improves endurance performance in healthy individuals. (2018, Jan-Feb). Retrieved from brain stimulation: https://www.brainstimjrnl.com/article/S1935-861X(17)30931-2/fulltext

Brain stimulation can improve athletic performance. (2017, october 12). Retrieved from science daily: https://www.sciencedaily.com/releases/2017/10/171012122736.htm

Brain stimulation can improve athletic performance. (2017, oct 12). Retrieved from university of kent: https://www.kent.ac.uk/news/science/15403/brain-stimulation-can-improve-athletic-performance

Can Shocking Your Brain Make You a Better Athlete? (2016, nov 17). Retrieved from outsi

de online: https://www.outsideonline.com/2137321/can-shocking-your-brain-make-you-better-athlete

Connectivity. (2016, march 21). Retrieved from MIT technology review: https://www.technologyreview.com/s/601054/brain-zapping-headphones-could-make-you-a


Enhancing Athletic Performance With Brain Stimulation. (2017, oct 13). Retrieved from psychology today: https://www.psychologytoday.com/us/blog/the-red-light-district/201710/enhancing-athletic-performance-brain-stimulation

Performance Enhancement by Brain Stimulation. (2017, Aug 8). Retrieved from NCBI: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5592297/

The Halo Sport headphones supercharge your brain to make you better at sports. (n.d.). Retrieved from digital trends: https://www.digitaltrends.com/health-fitness/halo-sport-neuropriming-headphones-video-review/

These Headphones Can Improve Performance and Reduce Fatigue! (n.d.). Retrieved from train right: https://trainright.com/halo-neuroscience-headphones-improve-performance-reduce-fatigue/

Is Non-Invasive Neurostimulation Safe?

What's the latest research on the safety of neurostimulation?

The word “safety” is defined by and limited to the absence of any kind of incident or situation of any serious and adverse side effect. This post is made upon an evidence-based approach with repeated experience of using tDCS on humans.

Computational models were used to compare dose to brain exposure in humans and animals. For meaningful standards of safety, dose response curve and dose metrics (current, current density, current duration, charge, and charge density) were reviewed. Special consideration was given to children and the elderly with mood disorders, epilepsy, implants, stroke etc.

With regards to the word “safety”, application of tDCS with all the protocols used to this date are safe, as reported in the review by NItsche:

Extensive animal and human evidence and theoretical knowledge indicate that the currently used tDCS protocols are safe. However, knowledge about the safe limits of duration and intensity of tDCS is still limited. Thus, if charge or current density is exceeded greatly beyond the currently tested protocols, which might be desirable, for example, for clinical purposes, we suggest concurrent safety measures.”

tDCS has been tested over thousand times on subjects varying world-wide, with no evidence of any bad/adverse results. With respect to thousands of experiments been carried out to check the adverse effects of tDCS, some experiments have especially been carried out to check its safety.

Based on the combined consequences gathered from all the research and experiments with tDCS, we have only found out that tDCS is only mildly associated with temporary headache and erythema (for duration of 40 minutes) in the stimulation side. Other side effects that are very less probable to occur include nausea, visual phosphine, vertigo and difficulty in concentration.

More than 100 experiments have been carried out in healthy controls and patients’ population using tDCS. If any side effects were observed; they were slight itching under the electrode, fatigue and nausea.

Other than that:

  • No neuronal damage was seen as assessed by serum neuron-specific enolase.
  • No pathological waveforms were seen on EEG.
  • No worsening of neuropsychological measures was observed after frontal lobe stimulation.
  • No heating occurred under the electrode.

The most severe side effects found in healthy volunteer were skin lesions on the area where electrodes were placed using 2mA current. These lesions were however very rare and most probably occurred due to insufficient skin-electrode contact. The problem could be avoided by using sodium chloride solution and regularly changing the sponge and carefully inspecting the condition of skin placed under the electrode, both, before and after the tDCS.

With no reports of serious side effects of tDCS, some proposed warnings are still to be very strictly and carefully abide by. Some of them are:

  • Stimulation sessions that last more than 40 minutes are for research purpose only.
  • Currents above 0.06mA are for advanced clinical or research purpose only.
  • Before using, always check if electrodes and strastism components are undamaged and clean.
  • If sponge electrodes are being used, it is recommended to use sodium chloride solution, regularly changing the sponge and carefully checking the condition of the skin before and after the tDCS session.
  • Electrode positions above cranial foramina and fissures should be avoided because these could increase the effective current density beyond safety limits.

To this date the use of tDCS has not been reported to have produced any adverse side effects or irreversible injury in human trials of over 33,200 sessions. This is said on the basis of a wide variety of subjects, which even includes people from potentially vulnerable populations. However, there are many safety recommendations with regard to the application of tDCS. When tDCS is given combined with EEG, conductive fluids between the electrodes must be prevented so that short circuiting is avoided. So, electrode gel, or vybuds’ dry electrodes, are preferable to saline solution.






A technical guide to tDCS. (2016, feb). Retrieved from Science Direct: https://www.sciencedirect.com/science/article/pii/S1388245715010883

Low intensity transcranial electric stimulation: Safety, ethical, legal. (n.d.). Retrieved from Clinical neurophysiology : http://www.cognitiveneuroscience.it/wp-content/uploads/2018/01/antal-et-al.pdf

Safety of Transcranial Direct Current Stimulation. (2016, oct). Retrieved from National Centre for Biotechnology Information: https://www.ncbi.nlm.nih.gov/pubmed/27372845

tDCS clinical research – Safety of transcranial Current Stimulation. (2015, april 24). Retrieved from Neuro Electrics: https://www.neuroelectrics.com/wiki/images/6/6a/NEWP201501-Safety_tCS.pdf

Transcranial direct current stimulation. (n.d.). Retrieved from Brain Stimulation: https://www.aipass.org/files/TDCS_State%20of%20the%20art.pdf




Using tDCS/tACS to Treat Post-Traumatic Stress Disorder (PTSD) in Veterans

What is PTSD?

PTSD is a mental condition of anxiety that is triggered by a terrifying event, either by experiencing it or by witnessing it. Traumatic events that trigger PTSD may include accidents, natural-human caused disasters, personal assaults etc. Several effective treatments, such as antidepressants as serotonin-specific reuptake inhibitors (SSRIs) and Cognitive Behavioural Therapy have been identified as treatments for PTSD, however even with these a number of patients continue to experience  symptoms. This means that treatment for chronic PTSD is still inadequate. The neuroscience has revealed that patients suffering from PTSD have altered functioning within several brain regions. Researchers say that a non-invasive electrical brain stimulation is a very effective treatment for Post Traumatic Stress Disorder (PTSD) by seemingly correcting the dysfunctional brain parts. It is believed that this, in turn, results in relief of PTSD symptoms.

The non-invasive transcranial Direct Current Stimulation tDCS has been experimented to treat many mental conditions like schizophrenia, depression, obsessive compulsive disorder, stroke and many more. When we talk about PTSD, one of the main problems with this disorder is the inability to escape fearful thoughts. Such as flashbacks of a friend being killed in a car accident. Such flashbacks can aggravate PTSD Symptoms which may also include anger, insomnia, nightmares and irritability.

tDCS decreases Emotional Arousal and Fear in PTSD patients:

Several studies were carried out that involved the use of tDCS to treat PTSD and their results were carefully observed.

During tDCS, a low-intensity current enters through one electrode and leaves through the other. The neurons, under the electrode where the current enters the body, become more likely to send signals, and under the electrode area where the current exits the skin, neurons are less likely to send signals.

A study involved 28 people suffering from PTSD. The researchers took help of an event marked by conditioned reflex, in which the patients predicted an unpleasant event after seeing a neutral stimulus. Coloured lights were marked as neutral stimulus and the unpleasant event attached to it was a harmless but highly annoying current to the fingers. The researchers put the electrode, through which current enters the skin, over a region which plays an important role in extinction learning and memory called ventromedial prefrontal cortex. The purpose was to make sure that those neurons fire off more likely to see if this improved extinction learning or the ability to predict an annoying event. At first, the 28 patients were made to see a colored light in a room, and, simultaneously, were given electric shock. Later, the patients were shown the coloured light without applying the electric shock. The later event is what we call extinction learning; the process where one learns that certain situations no longer anticipate an annoying event.

Fourteen patients received 10 minutes of tDCS just when they were experiencing extinction learning. The other 14 were given tDCS just after they underwent extinction learning, a time period known as extinction consolidation, when the information is being fed into the memory. After 24 hours, all of these patients were tested if they remembered the electric shock or not.

The results showed that the 14 veterans who received stimulation during the time of extinction consolidation showed slightly less perspiration on their hands (which was a sign of less fear/emotional arousal) than those who experienced the tDCS during extinction learning. An increase in hand sweat showed how well the patients had learnt and remembered that seeing colored light will result into a very unpleasant shock to their fingers.

It could be taken as giving the brain a little boost when people learnt that the colored lights no longer predict an electric shock and store that learning into memory, so people can better remember that they don’t need to fear the lights any longer.

For tDCS to be more effective, it is very important to control what the brain is doing during tDCS. That is why people were stimulated when they were doing an experimental task of extinction learning or consolidation of learning.



Brain stimulation technique shows promise in reducing fear in Veterans with PTSD. (2017, december 

9). Retrieved from US Department Of Veteran Affairs: https://www.research.va.gov/currents/1117-Brain-stimulation-technique-shows-promise-in-reducing-fear-in-PTSD.cfm

Current Status of Transcranial Direct Current Stimulation in Posttraumatic Stress and Other Anxiety Disorders. (2016, april 2). Retrieved from NEURAL ENGINEERING GROUP: https://www.neuralengr.org/uncategorized/new-paper-prospects-of-tdcs-for-ptsd/

Non-Invasive Br

ain Stimulation for Post-Traumatic Stress Disorder . (n.d.). Retrieved from Grantome: http://grantome.com/grant/NIH/R21-MH102539-02

Post-traumatic Stress Disorder Treatment Using Transcranial Direct Current Stimulation (tDCS) Enhancement of Trauma-focused Therapy. (n.d.). Retrieved from Smart Patients : https://www.smartpatients.com/trials/NCT02900053

tDCS improves behavioral and neurophysiological symptoms in pilot group with post-traumatic stress disorder (PTSD) and with poor working memory. (2014, feb 28). Retrieved from Taylor and Francis Group: https://www.tandfonline.com/doi/abs/10.1080/13554794.2014.890727




Treating chronic pain with non-invasive neurostimulation

Can non-invasive neurostimulation help treat chronic pain?

Chronic Pain:

Chronic pain is that pain which lasts beyond the time of one’s expected healing. Many patients e

xperience continuous pain despite having conventio

nal treatments like injections, medical and physical therapy, surgery etc. Non-invasive brain stimulation is gradually becoming a popular tool as an alternative treatment of chronic pain syndromes. tDCS has been explored in a variety of pain population with various chronic pain syndromes such as multiple sclerosis, central pain due to spinal cord injury, fibromyalgia, headaches, neuropathic and post-operative pain etc. It may non-invasively modulate cortical areas related to sensation and pain representations.

Recent evidences suggest that tDCS interacts with several neurotransmitters in the brain, such as serotonin, acetylcholine, dopamine. It also brings about changes in brain-derived neutrophic factors that deal with process of pain. It alters the 

way the nervous system send messages, for example pain messages t

hat the nervous system sends when nerve cells are damaged. Furthermore, it is also said that tDCS can upregulate and downregulate the functional connectivity of brain regions that are associated with motor, cognitive and pain processing.

Effects Of TDCS On Chronic Pain In Spinal Cord Injured Patients:

Sixteen spinal cord injured patients were randomly allocated to active or sham treatm

ent groups. tDCS was administrated by placing the anode over the dominant M1 and cathode over the contralateral supra orbit scalp area. Patients received either sham or active treatment for 5 consecutive days and 20 minutes daily.

In result, no adverse effects of the treatment were seen, while treatment seemed to have reduced the pain scores on VAS.

Effects Of TDCS On Chronic Pain In Fibromyalgia Patients:

48 female patients with (45 females having) fibromyalgia were randomly investigate

d with the results of 2 mA anodal tDCS given for 5 consecutive days, 20 minutes each day. Changes in pain, stress, daily functioning and psychiatric symptoms were observed. A small but significant improvement was seen under the active tDCS treatment. Fibromyalgia related daily functioning was improved. The stimulation was also well tolerated by the patients. And no adverse effects were observed.

This study suggests that tDCS has the potential to induce pain relief in patients suffering from fibromyalgia, without any adverse effects.

Effects Of TDCS On Chronic Pain In Phantom Limb Pain Patients:

Eight patients with unilateral lower and upper limb pain were enrolled and were given anodal tDCS (applied over motor cortex) for over 5 consecutive days, 15 minutes each day. tDCS induced a sustained decrease in phantom limb pain. Moreover, the patients reported a relief in pain each day along with a better condition to move their phantom limb.

The results showed that a 5-day treatment of motor cortex stimulation with tDCS can induce stable relief from Phantom limb pain.

tDCS is a unique and fine treatment to treat chronic pain. The intensity of current used in tDCS is so low that it cannot be felt while it is applied to the skull. The studie

s have shown that tDCS affects variety of brain area in a positive way. tDCS polarizes the brain cells under the electrodes and then alters the way the brain sends and receives messages. It is believed that this polarization can reverse the abnormal brain excitability responsible for pain.


A New Treatment for Chronic Pain. (n.d.). Retrieved from Headache and pain. a centre of palm beach: http://www.palmbeachpain.com/new-pain-treatments/41-a-new-treatment-for-chronic-pain.html

Effects of Transcranial Direct Current Stimulation (tDCS) on Chronic Pain in Spinal Cord Injured Patients. (2017, march 22). Retrieved from Spine Research: https://spine.imedpub.com/effectsof-transcranial-direct-current-stimulation-tdcs-on-chronic-pain-in-spinal-cord-injured-patients.php?aid=14974

Evidence-based review of transcranial direct current stimulation (tDCS) for chronic pain syndromes. (2017, march-april). Retrieved from brain stimulation: https://w


Immediate and Sustained Effects of 5-Day Transcranial Direct Current Stimulation of the Motor Cortex in Phantom Limb Pain. (2015, april 18). Retrieved from NCBI: https://www.ncbi.nlm.nih.gov/pubmed/25863170

Stimulating the brain without surgery in the management of chronic pain in adults. (2018, april

 13). Retrieved from cochrane: http://www.cochrane.org/CD008208/SYMPT_stimulating-brain-without-surgery-management-chronic-pain-adults

Transcranial direct current stimulation as a treatment for patients with fibromyalgia: a randomized controlled trial. (2015, JAN). Retrieved from NCBI: https://www.ncbi.nlm.nih.gov/pubmed/25599302



tDCS/tACS to treat migraines

Are you suffering from migraines? Try something new.

What are migraines?

Migraines are severe, recurring headaches. Typically these headaches affect only one half of the head. They are pulsating in nature and can last from about two to 72 hours. Associated symptoms with migraines may also include sensitivity to light, sound and smell, nausea and vomiting etc. Normal recommended treatments include pain medication such as paracetamol and ibuprofen. Approximately 15% around the world suffer from migraines and apparently, no effective solution has been found.

Effective Treatment of Migraine; tDCS:

Recently, mu

ch importance has been given to transcranial direct current stimulation that alters the mechanism underlying the cortical excitability which is said to have become dysfunctional during migraine. tDCS have been reported to be safe and effective tool in dealing with the cortical excitability, activation and plasticity In migraine.

Experiments on Migraine Using tDCS:

Thirteen patients, with chronic migraine, were randomized to get active and sham tDCS of 2 mA for 20 minutes over 4 weeks. These patients received over 10

 session of stimulation during this time period. The data for results was collected before, during and after the treatment. A significant improvement was seen in the follow up period in the active tDCS groups only. Co

mputational model studies showed that the current flew into different regions of the cortical and subcortical that are highly associated with the migraine pain. The current was also generated in thalamus, cingulate cortex, insula and brainstem regions.


ent studies have shown that patients with chronic migraine pain have a positive response when tDCS is directed towards the anodal motor cortex. These effects may be related to electrical currents induced in pain-related to cortical and subcortical regions.

Another study, including 13 patients with chronic migraine, used tDCS as a preventive migraine therapy. After 10 sessions, the patients reported a 37% decrement in their pain intensity. But the symptoms kicked in after four weeks of treatment. The assistant professor of the study said that it was important that repetitive sessions were arranged to revert ingrained changes in the brain related to migraine.

Other studies have reported that stimulation of the motor cortex decreases the chronic pain. However, this study provided the first known mechanistic proof th

at tDCS over the motor cortex might work as a successful precautionary remedy in complicated and complex, chronic migraine cases, where attacks are more constant and flexible to traditional treatments.

This powerful method of brain stimulation and modulation has determined compelling results in different kinds of chronic pain, and has proved to be more eff

ective regarding enhancing the pain tolerance than other forms of transcranial stimulation. tDCS has promising effects for the medication and treatment of chronic pain disorders, including other of its amazing features such as small portable size, economic cost, and capability to provide a more stable placebo condition.




Brain stimulation in migraine. (n.d.). Retrieved from NCBI: https://www.ncbi.nlm.nih.gov/pubmed/24112926

Migraine patients find pain relief in electrical brain stimulation. (2012, april 19). Retrieved from mechigan news: https://news.umich.edu/migraine-patients-find-pain-relief-in-electrical-brain-stimulation/

tDCS for Migraine Headache. (n.d.). Retrieved from The Brain Stimulation Clinic: http://www.transcranialbrainstimulation.com/Migraine

tDCS-Induced Analgesia and Electrical Fields in Pain-Related Neural Networks in Chronic Migraine. (2012, april 18). Retrieved from NCBI: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4166674/#R7

Transcranial Direct Current Stimulation (tDCS) of the visual cortex: a proof-of-concept study based on interictal electrophysiological abnormalities in migraine. (2013, march 11). Retrieved from Springer link: https://link.springer.com/article/10.1186/1129-2377-14-23


tDCS/tACS to treat insomnia

Suffering from insomnia? Try a treatment that's shown some efficacy, but needs more research from contributors like you.

What causes insomnia?

A person suffering from insomnia has trouble in falling and staying asleep. Insomnia might occur due to physical or psychological stress, or may be a side effect of a pharmacological medication. It is considered that cortical activity, when pathologically altered, leads to insomnia. This regulation of cortical activation follows circadian rhythms that allow the transition between sleep and wakefulness.

Fortunately, studies have shown that neuromodulation through non-invasive brain stimulation in the form of transcranial direct current stimulation can alter cortical excitability and can be used to probe effects on different parameters of sleep. It has been shown that tDCS has the ability to cause modifications in EEG parameters of a person’s sleep and wake such as synchronization.

How does tDCS work?

In tDCS, the current that flow in the brain is triggered through a positive and a negative electrode (anode and cathode, respectively). The basic mechanisms of tDCS include polarization of neuronal membranes under the electrodes placed on the skull. Anodal and cathodal tDCS show antagonistic effects on cortical excitability. Anodal stimulation increases cortical excitability, whereas, on the other hand, cathodal tDCS decreases cortical excitability. Hence, the placing of the anode over a particular target cortical area of the brain is capable of modifying the excitability of this area by rising depolarization of cortical neuronal cells.

Experiments on Insomnia Using tDCS:

In an experiment carried out by Lukas Frase and colleagues, the effects of two different tDCS parameters and a sham stimulation on the sleep cycle of 19 healthy participants was compared.

Bi-frontal anodal stimulation, seemed to increase the arousal, and consequently, decreased the total sleep time in comparison to the other two interventions. Bi-frontal cathodal stimulation, expected to decrease arousal, did not increase the total sleep time, may be because there is a ‘ceiling’ or limit after which the good sleepers do not sleep any more. EEG analysis finally proved that the anodal stimulation increased the arousal, while cathodal stimulation did the other way and decreased the arousal.

It was, at last, concluded that by using anodal tDCS total sleep time can be decreased. The researchers hope this knowledge can contribute to future treatments for disturbed arousal and sleep.

Another research study comprising of 26 neuropsychiatric patients ( with stroke, dysphagia, pain, hereditary spastic paraparesis, Parkinson’s disease, aphasia, depression) were made to go through tDCS treatment. tDCS montage for each pathology was different. The current intensity of the stimulation was kept at 2mA and was delivered for 5 consecutive days, 20 min per day. The sleep quality at baseline (T0) and after the tDCS treatment (T1) was assessed.

Despite of the fact that the sample size was small and different tDCS montages were used, data from the observational study showed that anodal tDCS for five consecutive days enhanced the quality of sleep and improved its efficiency.

tDCS could be a non-invasive and valuable new tool for managing sleep disorders. Researchers that studied the total sleep time and other sleep disturbances propose that tDCS may be potentially beneficial to modulate cortical activity linked with insomnia and to adjust sleep adequacy.


Modulation of Total Sleep Time by Transcranial Direct Current Stimulation (tDCS). (2016, may 4). Retrieved from Neuropsychopharmacology: https://www.nature.com/articles/npp201665

TDCS Can Change Sleep Duration. (2016, october 7). Retrieved from bipolar news: http://bipolarnews.org/?p=3884

The Modulatory Effect of Sleep on tDCS. (2017, sept). Retrieved from http://epubs.surrey.ac.uk/845444/1/FINAL%20THESIS_James%20Ebajemito.pdf

Transcranial Direct Current. (n.d.). Retrieved from SCIENCE MEDICAL CENTRE: https://www.jscimedcentral.com/SleepMedicine/sleepmedicine-3-1060.pdf

Transcranial direct current stimulation improves sleep in patients with post-polio syndrome. (2013, aug 26). Retrieved from Science Daily: https://www.sciencedaily.com/releases/2013/08/130826143724.htm



tDCS in the Treatment and Prevention of Alzheimer’s Disease

Can non-invasive neurostimulation prevent age-related cognitive decline, including Alzheimer's Disease?


Alzheimer’s is a disease characterized by progressive neurodegenerative disorder and is also accountable for dementia (cognitive/memory decline) in old people. According to statistics from 2010, people who had dementia due to Alzheimer’s Disease (AD), at the age of about 60, was 4.02%, and it has been projected to increase drastically by 2030. Treating AD is very costly, with overall spending estimated to be around $422 billion in 2009. Presently, basic pharmacological treatments available for AD patients are N-methyl-D-aspartate receptor partial antagonist and cholinesterase inhibitors. But since these treatments have extremely bad side effects and limited response there is a dire need of alternative treatments for AD.


Transcranial Direct/Alternating Current Stimulation In Treating Alzheimer

Since treatments presently available for AD are not really appreciably effective, scientists have recently figured out that brain stimulation is another considerable alternative as a clinical treatment of Alzheimer’s. Non-invasive transcranial direct current stimulation of the brain has been proved to be one of those methods in treating and preventing Alzheimer’s Disease. It also has considerably better results than other treatment options. To date, tDCS has shown beneficial effects in treating several other diseases as well.


  1. tDCS Improves Mini-Mental State Examination Score in AD Patients:

A number of experiments have reportedly observed improved cognitive functions of patients with AD. In one of the experiments carried out in Egypt, Khedr and colleagues randomly divided 34 participants, suffering from AD, in 3 groups. Participants of cathodal and anodal groups, both, underwent daily tDCS continuously for 10 days with a low current intensity of 2 mA given to them for about 25 mins/day. A significant improvement was observed on the MMSE score after the experiment, which lasted for about 10 days.

  1. tDCS improves Visual Recognition in AD patients:

Similarly, Boggio and colleagues have been reported to demonstrate that tDCS used on the temporal cortex and left DLPFC enhanced VRM (Visual Recognition Memory) of patients with Alzheimer’s Disease. Ten AD patients were enrolled by the researchers for this experiment, who received two real stimulations and one sham stimulation (stimulation that uses placebo effects). Real stimulation was incited on left DLPFC with a low current intensity of 2 mA for a time period of 30 seconds/session, whereas, the sham stimulation was only carried out for the first 30 seconds. Neurophysiological tests were generated during tDCS stimulation in which it was found that VRM tasks were significantly improved when tDCS was given over left DLPFC and temporal cortex. After which the tDCS was applied bilaterally over the temporal regions through anodal electrodes on the scalp. This was done for 5 days in a week and the current intensity was kept at 2mA for 30 mins a day. The results were observed after the 5-day treatment and it was found that VRM was actually enhanced to great extent, lasting for almost 1 month.

  1. tDCS improves Memory Conditions in AD patients:

Likewise, another experiment was carried out by Cotelli and colleagues. A therapy of anodal tDCS with computerized memory training was developed by them. 36 patients with AD were randomly assigned into three groups. The first group was made to go through anodal tDCS along with computerized memory training, while the second group was given placebo tDCS with computerized memory training. The third group was given motor training and anodal tDCS. The tDCS stimulation was generated for 5 days a week, 25 mins/day with a current intensity of 2 mA. The results showed remarkable improvement.

Most of these clinical experiments were small, so conditions and outcomes of stimuli were different, due to which the results also differ from study to study.



Studies are continuously investigating techniques of brain stimulation as a therapeutic treatment of AD. Although, some researches and experiments have given the best of the results, there is much more that still needs to be discovered. However, stimulations that enhance memory and cognitive memory are very effective and promising. Other than this, stimulations targeted at different regions of the brain combined with treatments like cognitive training are reported to produce more positive and good results. Although the field of tDCS is still immature, because it is safe, tolerable, and economic for patients with AD, the studies show that the use of tDCS have grown in decades.



Brain Stimulation in Alzheimer’s Disease. (2018, May 22). Retrieved from Frontiers in Psychiatry: https://www.frontiersin.org/articles/10.3389/fpsyt.2018.00201/full

Transcranial Direct Current Stimulation. (2017, march 31). Retrieved from Brain & NeuroRehabilitation: https://synapse.koreamed.org/Synapse/Data/PDFData/0176BN/bn-10-e4.pdf

Transcranial direct current stimulation for depression in Alzheimer’s disease. (2017, June 19). Retrieved from https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5477338/

Transcranial direct current stimulation improves recognition memory in Alzheimer disease. (2008, Aug 12). Retrieved from Neurology: http://n.neurology.org/content/71/7/493.short

Treatments | Alzheimer’s, ADHD, Autism, Brain Injury Treatment. (n.d.). Retrieved from The Neuro Cognitive Institute: http://neuroci.com/treatments/

Using transcranial direct current stimulation to treat symptoms in mild cognitive impairment and Alzheimer’s disease. (2017, oct 18). Retrieved from Future Medicine: https://www.futuremedicine.com/doi/full/10.2217/nmt-2017-0021

Using transcranial direct current stimulation to treat symptoms in mild cognitive impairment and Alzheimer’s disease. (2017, oct 18). Retrieved from NAtional Centre for Biotechnology Centre: https://www.ncbi.nlm.nih.gov/pubmed/29043928



Potential Benefit of Using Transcranial Direct/Alternating Current Stimulation in Boosting Memory

The world we live in overwhelms our senses with an overabundance of knowledge. Handling such an abundant amount of knowledge every day and every second is not within a human brain’s capacity. The most important key factor, our attention/focus, is a remarkable cognitive process that enables us to prioritize the most important piece of information to be handled at the right time in the right way.

Today, scientists have worked day and night to bring in new scientific ways that can help us boost our memory and thus have introduced one of the ways; Neurostimulation.


Neurostimulation is a process of purposely altering the activity of brain (certain regions of the cortex; an important layer of the brain associated with memory, attention, cognition, language and consciousness) applied either invasively or non-invasively. Here, we are talking about non-invasive neurostimulation and particularly about electromagnetic methods such as transcranial electrical stimulation that involves direct current (tDCS) or alternating current (tDACS). [CITATION San17 \l 16393 ] This is a newly developed technique which regulates and adjusts cortical excitability and activity. tDCS/ tACS are thought to have an effect on neural membrane potentials by electrical stimulation using random frequencies. It is said that these stimulations induce long-term-potentiation- like cortical plasticity. They are very beneficial for increasing blood flow, improving depressed symptoms and for learning faster.


Transcranial direct current stimulation (tDCS) is a scientific way of neurostimulation that involves the use of constant and low current delivered directly to the targeted brain area through small electrodes.

It uses “anode” and “cathode”, two electrodes of different polarities that are connected to a 9-V battery. A small amount of current with low intensity is passed from one electrode to another while allowing the current to rise and then keeping it constant for a certain time. Sufficient current penetrates this way into the brain. [CITATION Lei14 \l 16393 ]


  1. tDCS Improves Learning:

tDCS can improve learning in people suffering from atypical brain development at structural and functional levels. An improvement in learning motor skills task was seen when the primary motor cortex was stimulated with tDCS. A study found that tDCS actually improved the rate of learning when used on the right inferior frontal and right parietal cortex. Another study found that daily sessions of tDCS significantly enhanced motor sequence learning.[ CITATION 13H18 \l 16393 ] Since the electrical current is kept quite low, any kind of major physical side effects, like tissue damaging, have not been observed in experimentations yet. [CITATION Sci13 \l 16393 ]

  1. tDCS Enhances Language Learning and Abilities:

tDCS improve language fluency and language memory when left frontal lobes are stimulated. tDCS have also been reportedly said to improve language performance and word retrieval in people with language impairment. It has also been reported that tDCS brings improvements in verbal categorization, grammar learning and reading efficiency. It is argumentative that tDCS is a reassuring tool to evaluate the working of lateral Prefrontal Cortex.[CITATION Lan15 \l 16393 ]

  1. tDCS Improves Sleep Quality:

Memory boosting is indirectly associated with the quality of sleep we get. While it is common to have sleep disorders in manic and depressed phases, it is being clearly understood that sleep disorders are one of the major causes of unclear focus and poor attention level in a person. In a study, 3 weeks of continuous anodal stimulation of the pre-motor cortex resulted in significantly improved sleep quality and social behaviour in comparison to control treatments. Cathodal tDCS was given on the right cerebellar cortex and anodal tDCS over the left dorsolateral prefrontal cortex. The intensity of current was 2mA and was given for 20 minutes. During several investigations, it was surprisingly found that prefrontal-cerebellar tDCS are actually effective.[ CITATION 13H18 \l 16393 ]

[CITATION Pre14 \l 16393 ]

  1. tDCS Improves Working Memory:

Working memory is a short term memory concerned with perception of immediate conscious and processing of linguistics. Working memory is of great importance for productive human behavior. Stimulation of the dorsolateral prefrontal cortex has been reported to improve the working memory of a person. But it was noticed that the effect of tDCS was more beneficial to those people with a history of relatively low working memory. [ CITATION Aug17 \l 16393 ]

  1. tDCS Improves Memory Enhancement:

tDCS have somewhat proved to be a productive technology to improve physical and cognitive performance. tDCS improve the neural activity by conducting a weak current through the scalp via electrodes and then transferring the current back towards the exit electrodes. The mechanism of modification of tDCS involves both synaptic and non synaptic actions on cells(neural/non-neural). [ CITATION tDC17 \l 16393 ]


Transcranial direct/alternating Current (tDCS) is one of the most talked about and promising techniques of neurostimulation. Just as discussed above, tDCS are very beneficial for boosting one’s memory. As compared to other neurostimulation devices, this one is relatively small and portable (operated with battery). It is also less risky as very minor side effects are reported to date if any. Their friendly and easy-to-use nature makes it highly accessible for new users and people who are keenly interested in trying it out on themselves on their own. Different tutorials are also available on how to make the best use of them. [ CITATION Tra09 \l 16393 ]






13 Health Benefits of tDCS: A Comprehensive Review. (2018, feb 22). Retrieved from Self Hacked: https://www.selfhacked.com/blog/tdcs-benefits/

about Transcranial Alternating Current Stimulation. (2014). Retrieved from Science Direct: https://www.sciencedirect.com/topics/neuroscience/transcranial-alternating-current-stimulation

Augmentation of working memory training by (tDCS). (2017, April 21). Retrieved from Nature: https://www.nature.com/articles/s41598-017-01055-1

Can transcranial electrical stimulation improve learning? (2013, Oct). Retrieved from Science Direct: https://www.sciencedirect.com/science/article/pii/S187892931300025X

Language and Memory Improvements following tDCS of Left Lateral Prefrontal Cortex. (2015, Nov 3). Retrieved from National Centre for Biotechnology Information: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4631603/

Non-invasive Brain Stimulation. (2017, 12 06). Retrieved from Springer Link: https://link.springer.com/article/10.1007/s41745-017-0046-0

Prefronto-Cerebellar Transcranial Direct Current Stimulation Improves Sleep Quality. (2014, Dec 7). Retrieved from National Centre for Biotechnology Information: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4273569/

tDCS for Memory Enhancement. (2017, Jan 11). Retrieved from National Centre for Biotechnology Information: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5225120/

Transcranial direct current stimulation. (2009, May). Retrieved from Scielo: http://www.scielo.br/scielo.php?pid=s1516-44462009000500006&script=sci_arttext&tlng=en


Transcranial Direct/Alternating Current Stimulation in Boosting Memory

Noninvasive brain stimulation techniques are gaining attention due to their safety in modulating brain dynamics. Promising applications include treatment of various central nervous system diseases and improvement in cognitive functions. Transcranial electrical stimulation provides noninvasive brain modulation using direct current, alternating current and random noise stimulation (Paulus, 2011).

A weak direct electrical current is applied through the scalp using two or more electrodes in the  transcranial direct electrical stimulation tDCS technique. This induces brain excitability through cathodal hyperpolarization and anodal depolarization (Paulus, 2011). The induced effects depend on polarity, duration and intensity of electrical stimulation.

Transcranial alternating current stimulation is same as direct current in case of low intensity and electrodes. But it uses sinusoidal current through the scalp for electrical stimulation (Woods 2011). Several studies have been carried out that showed that transcranial direct/alternating current has a positive impact on motor, memory, perception and cognitive functions.

Cognitive processes include perception, memory, learning, and long-term memory formation. Induction of transcranial electrical brain stimulation enhances the cognitive functions. Direct current stimulation occurs through spontaneous cortical activity and alternating current modulate cognition by interfering with the oscillations of cortical networks (Kuo, 2012)

Transcranial stimulation of the brain through weak direct current induction serves a non-invasive and painless technique (Nitsche, 2000). In their study, induction of direct current through the scalp for modulating motor cortex excitation, showed up to 40% of the excitation changes that last for several minutes after end of stimulation. Stimulation was achieved by membrane polarization inducing anodal stimulation and inhibiting cathodal stimulation.

Weak direct current induction leads to cerebral excitability. Fregni et al (2005) evaluated “the effect of anodal stimulation of dorsolateral prefrontal cortex (DLPFC) on working memory”. A letter-based working memory task was performed by fifteen individuals during anodal stimulation of DLPFC. Out of these seven performed the same task but with cathodal stimulation. Results showed the increased performance of individuals with anodal stimulation.

Another study was carried out to investigate the association of slow oscillations on memory during sleep. Induction of transcranial slow oscillations of 0.75 Hz in early sleep increased the retention of declarative memory in healthy subjects and also improved the slow wave sleep and slow spindle activity in the frontal cortex. Stimulation of the brain by 5Hz oscillations during rapid eye movement sleep had no effect on declarative memory (Marshall, 2006). Based on this, another study was carried out to rule out the effect of slow oscillations during waking on brain and memory encoding. It was concluded that the effect of oscillation and memory depend on brain state, as when the awake brain transmitted stimulation by responding to oscillations and facilitated encoding. Transcranial oscillations didn’t improve memory when applied after learning, while it showed enhanced encoding of hippocampus dependent memory when induced during the process of learning (Kirov, 2009)

Transcranial alternating current stimulations have an enhanced effect on human cognitive functions. Antonenko et al (2016) conducted research on young and older healthy individuals. Transcranial alternating current of 6Hz was applied to the brain for 20 minutes during a language learning process. The results were in support of the evidence that alternating current improves human cognition through direct stimulation of task-related brain oscillations.



Antonenko D, Miriam Faxel, Ulrike Grittner,Michal Lavidor and Agnes Flöel, 2016. “Effects of Transcranial Alternating Current Stimulation on Cognitive Functions in Healthy Young and Older Adults”. Neural Plast: 4274127. Doi: 10.1155/2016/4274127. PMCID: PMC4889859. PMID: 27298740

Fregni, F, Boggio, P.S, Nitsche, M. et al, 2005. “Anodal transcranial direct current stimulation of prefrontal cortex enhances working memory”. Exp Brain Res: 166: 23. https://doi.org/10.1007/s00221-005-2334-6

Kirov R, Carsten Weiss, Hartwig R. Siebner, Jan Born, and Lisa Marshall, 2009. “Slow oscillation electrical brain stimulation during waking promotes EEG theta activity and memory encoding”. PNAS; September 8, 2009. 106 (36) 15460-15465; https://doi.org/10.1073/pnas.0904438106

Kuo M F, Michael A. Nitsche, 2012. “Effects of Transcranial Electrical Stimulation on Cognition”. Clinical EEG and Neuroscience, Volume: 43, issue: 3, page(s): 192-199. https://doi.org/10.1177/1550059412444975

Marshall, L., Helgadóttir, H., Mölle, M., and Born, J. (2006). “Boosting slow oscillations during sleep potentiates memory”. Nature 444(7119):610-3. doi: 10.1038/nature05278

Nitsche MA, Paulus W, 2000. “Excitability changes induced in the human motor cortex by weak transcranial direct current stimulation”. J Physiol. 2000 Sep 15; 527 Pt 3:633-9. PMID: 10990547 PMCID: PMC2270099

Paulus W, “Transcranial electrical stimulation (tES – tDCS; tRNS, tACS) methods”.Neuropsychol Rehabil. 2011 Oct; 21(5):602-17. Doi: 10.1080/09602011.2011.557292. Epub 2011 Aug 5.