Homomorphic Encryption Vs. Multiparty Computation

Bleeding edge encryption techniques allow one to monetize their personal health information without sacrificing privacy.

Encryption:

Encryption is the conversion of information into a code unreadable for unauthorized users by the use of an algorithm. Encryption is important when you don’t want anyone else to have access to your private data, such as brainwave data, selfie video data, or personal health data. There are many ways to compute (do math on) the encrypted data without knowing whose information it is about out of which, two are: Homomorphic Encryption and Multiparty Computation.

Homomorphic encryption is a kind of encryption in which the data is converted into a ciphertext which can be later analysed and worked on as it was still in its original form. The ciphertext is an encrypted version of the input data. It is operated on and then decrypted to obtain the desired output. This encryption allows us to perform complex mathematical operations on encrypted and secured data. It transforms one data set into another without harming the relationship between elements of both sets.

Multiparty computation is used to evaluate the inputs of two or more parties while keeping their inputs hidden from each other. This is done when different parties wish to jointly compute a function to their inputs in such a way that there certain security properties are preserved.

In simpler term, encryption allows us to hide data in a way that appears meaningless to anyone except those who have access to the secret decryption key. 

 

PROTECTION OF DATA THROUGH HOMOMORPHIC ENCRYPTION:

There have been many attempts to secure genomic privacy of biologically researched data using cryptographic methods. Particularly, it has been suggested that the privacy can be protected through homomorphic encryption.

The math on brainwave data recorded, of secret participants, using EEG while watching TV commercials, can be done through homomorphic encryption without decrypting the data.

The companies that get the brainwave data, never want to reveal the identity of their participants, that is why they send the samples in an encrypted form, to the lab, where the computations are done using homomorphic encryption, and the predictions (results) are sent back, to the company, in the encrypted form; where only they can decrypt it back using decryption keys. In this way, the identity of the person is never disclosed. The data is encrypted, also because companies and labs are bound by regulations and participant’s agreements to handle his data confidentially.

PROTECTION OF DATA THROUGH MULTIPARTY COMPUTATION:

Multiparty computation can be implemented using different protocols, such as Secret Sharing, in which the data from each party is divided and computed on separately. Then after combining again, it provides the desired statistical results. Security in multiparty computation means that the players’ inputs remain secured (except for the results that are computed) and the results computed are correctly. The security is supposed to be preserved In the face of any sort of adversary. Intuitively, no party learns about any other party’s inputs.

All in all, computation of encrypted data is an interesting topic that explains how cryptography faces the hardest problem of protecting data in use. This is just an overall review about what these two methods of computation have to offer us. The past few years have seen the most significant advances in making the use of these two technologies on more wider-scale.

 

For more information, see the project at OpenMined.org

 

 

References

BUILDING SAFE ARTIFICIAL INTELLIGENCE. (n.d.). Retrieved from open mined: https://www.openmined.org/

Computing Over Encrypted Data. (2017, may 29). Retrieved from Enigma: https://blog.enigma.co/computing-over-encrypted-data-d36621458447

homomorphic encryption. (n.d.). Retrieved from Search Security: https://searchsecurity.techtarget.com/definition/homomorphic-encryption

Homomorphic Encryption Market Size, Worldwide Analysis, Design Competition Strategies, Company Profile, Development Status, Opportunity Assessment and Industry Expansion Strategies 2027. (2018, june 7). Retrieved from 14 News: http://www.14news.com/story/38373250/homomorphic-encryption-market-size-worldwide-analysis-design-competition-strategies-company-profile-development-status-opportunity-assessment-and

Private predictive analysis on encrypted medical data. (2014, Aug). Retrieved from Science Direct: https://www.sciencedirect.com/science/article/pii/S1532046414000884

Secure multi-party computation made simple. (2006, Feb 1). Retrieved from Science Direct: https://www.sciencedirect.com/science/article/pii/S0166218X05002428

 

 

What is neuromarketing?

Neuromarketing enables one to substantially profit off the multi-billion dollar super-computer between their ears.

Neuromarketing is the science about your customer’s minds. It includes the direct use of brain imaging, scanning or other brain activity measurement technology to predict the subject’s response towards specific products, packaging or any other marketing element. It is the application of neuroscience to marketing.

Every year, billions of dollars are being spent on advertising campaigns. But conventional techniques have failed to predict how a customer feels when he is exposed to an advertisement. Neuromarketing offers cutting edge methods to know how a customer’s brain actually works and what effect does marketing have on the consumers’ population.

Neuromarketing researchers believe that consumers sometimes make subconscious decisions in a split of second. They believe that consumer’s decision can be driven through changing their emotions.

How Neuromarketing Works:

Knowing how an advertisement captures a consumer’s attention is what neuromarketing is all about. Research data is gathered by using certain biometrics that include:

  1. Eye tracking: tracking eye movement to understand which part of the advertisement is most appealing to the viewer.
  2. Facial coding: Testing facial expressions to learn certain responses about a product or an advertisement.
  3. Skin response and electrodermal activity: measures sweat gland secretions and different levels of excitement and arousals.
  4. Electroencephalography (EEG): measures electrical activity in the brain which is linked with increased or reduced focus and/or excitement levels.

Use Of EEG in Neuromarketing:

EEG biosensors makes the neuromarketing research easy. This allows the researchers to record consumer’s response in the right place such as movie theatre, bars etc. The biosensors can be placed on the head that accurately measure the brain activity of the subject. The changes in the electrical activity of the brain determines the emotional response of the person being tested, also whether he is engaged in watching the advertisement or not at all focused.

EEG can also reveal that the consumer was very attentive during the first 30 seconds of the advertisement but lost interest in the last 30 seconds. This feedback, in, turn, could better help in making the last 30 seconds of the advertisement even more effective.

Earning Money by Watching Advertisements and Using EEG:

This has also become a popular way of making money. This simple yet very beneficial tool can be used as a source of earning by using EEG to record your brainwaves while watching TV commercials and advertisements at home. People get paid by different companies and brands for selling their brainwave data. The general price paid per brainwave recording is between $80 and $100 per hour.

Different companies recruit people and pay them for watching their advertisements and recording their brainwaves by using electroencephalogram scans. It records on a second-by-second basis regarding how people respond to the commercial.

Neuromarketing has helped marketers make engaging and effective commercials. This not just benefits the marketers but the customers as well in enhancing their experience with a brand or product long before they consider buying it. This field is gaining unbelievable popularity among marketing and advertising professionals and is growing day by day.

 

 

References

Making Ads That Whisper to the Brain. (2010, nov 13). Retrieved from https://www.nytimes.com/2010/11/14/business/14stream.html: https://www.nytimes.com/2010/11/14/business/14stream.html

Neuromarketing and EEG: Measuring Engagement in Advertising. (2018, june 14). Retrieved from NeuroSky: http://neurosky.com/2016/08/neuromarketing-and-eeg-measuring-engagement-in-advertising/

Neuromarketing: Marketers scan consumers’ brains to test their ads. (2015, nov 5). Retrieved from CBC: http://www.cbc.ca/news/technology/neuromarketing-brainsights-1.3303384

Neuromarketing: The New Science of Consumer Behavior. (2011, jan 14). Retrieved from springer link: https://link.springer.com/article/10.1007/s12115-010-9408-1

What is Neuromarketing? (n.d.). Retrieved from Neuromarketing: https://www.neurosciencemarketing.com/blog/articles/what-is-neuromarketing.htm

 

 

 

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!

 

References

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

 

 

What is neuroplasticity?

Is it true that neurostimulation helps your neurons make connections?

Neuroplasticity, also known as brain plasticity, is the ability of the brain to be adapted to any change in its surrounding throughout its life. From the time we are born until the day we die, the cells in our brain keep reorganizing according to our needs of change. Neuroplasticity is constantly at work throughout our lives. The connections within our brain are either becoming stronger or weaker. Younger people’s brains change more easily, because their brains are very plastic. Aged people lose their brain plasticity and become more firm and fixed in their thinking, learning and perceiving. In clinical context, the term neuroplasticity determines how quickly a patient recovers after a brain injury i.e. to regain independence to perform daily life activities (self-care, dressing, personal hygiene etc.)

 

It has been recognized that not all psychiatric and neurological behavioural indicators are solely because of abnormality, but because of alteration in the functionality of the brain regions. In this context, brain region becomes an important target of neuromodulatory interventions such as transcranial direct current stimulation. The advancement in neuroimaging techniques have made ways for us to non-invasively visualize different regions of the brain. tDCS has been used to improve various areas of cognitive functions. Some of them are briefly described ahead.

 

tDCS to improve learning and boost memory:

tDCS has been proven to be potentially beneficial in improving memory and learning in people with atypical brain development. With the help of several researcher’s work, it was proposed that tDCS when used on the right inferior frontal and right parietal cortex improved memory conditions. tDCS has also been reportedly said to improve language performance and word retrieval in people with language impairment.

 

tDCS to enhance motor skills:

In a randomized study, it was observed that tDCS could enhance motor skills in patients with chronic stroke. The transcranial direct current stimulation (tDCS) was positioned over the motor cortex (M1) (through anode) and contralesional forehead (through cathode) challenging fine motor skill task. The results showed significant increase in motor skills relative to any other treatment.

tDCS to treat Chronic Pain:

 

Different experimental research work done on patients with fibromyalgia and phantom limb pain suggested that tDCS had the capacity to upregulate and downregulate the functional connectivity of brain regions that are associated with motor, cognitive and pain processing. Patients with phantom limb pain were given anodal tDCS (applied over motor cortex) for over 5 consecutive days and they reported reduction in their pain.

 

tDCS to enhance athleticism:

A “Cycling Time to Task Failure Test” was conducted among several athletes in which it was revealed that participants who received anodal stimulation biked longer than those who received sham or cathodal stimulations. The researchers suggested that the better performance could be due to higher excitability of motor cortex leading to a decrement in effort and increment in endurance of the athletes.

 

tDCS to treat Alzheimer and other diseases:

It was reported that tDCS used on temporal cortex and left DLPFC enhanced VRM (Visual Recognition Memory) in patients with Alzheimer Disease. In different research work, it was noticed that tDCS also proved great in enhancing overall memory conditions of Alzheimer patients when applied bilaterally over the temporal regions through anodal electrodes on the scalp.

 

 

References

 

A brain network perspective on tDCS induced neuroplasticity: Single versus dual or multiple sites stimulation. (2017, march). Retrieved from science direct: https://www.sciencedirect.com/science/article/pii/S1388245716306897

IMPROVING NEUROPLASTICITY 

AND MOTOR LEARNING BY BRAIN. (2016, feb). Retrieved from https://pdfs.semanticscholar.org/536d/5ef2ae380aab59630ceeda72c54de0751ac8.pdf

Induction of Neuroplasticity by Transcranial Direct Current Stimulation. (2016, dec 1). Retrieved from NCBI: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5219570/

WHAT IS NEUROPLASTICITY? (n.d.). Retrieved from brain works neurotherapy: https://brainworksneurotherapy.com/what-neuroplasticity

 

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.

 

References

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

-better-athlete/

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.

 

 

 

 

References

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

 

 

 

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.

References

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

ww.brainstimjrnl.com/article/S1935-861X(17)30196-1/fulltext

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.

Differ

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.

 

Refer

ences

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.

References

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

 

 

Alternative Modalities in BMI Biometrics

While most medical applications of the EEG BMI require clean data, recorded artifacts from facial movements and eye-blinks have been shown to be exceedingly accurate in classifying individuals.

Historically, when a subject undergoing an EEG recording session blinks or twitches their face, a sharp spike appears on the recording trace that renders that epoch unusable. While most medical applications of the EEG BMI require clean data, recorded artifacts from facial movements and eye-blinks have been shown to be exceedingly accurate in classifying individuals.

In addition to facial movements, eye-blinks are now being integrated with EEG systems to achieve a higher classification rate than using brainwaves alone. In [34], it was discovered that using a cheap, consumer-version EEG headset (the Neurosky Mindwave) achieved a 99.4% classification rate by discriminating eye-blinks in addition to EEG brainwaves. This represents the highest classification rate for a significant subject size (31 persons) to date using an EEG instrument.  Eyeblinks may have some disadvantages relative to brainwave patterns (such as forced-volition and lack of continuous verification), and are likely to be more prone to mimicry, but may be easier to train. Integrated with the continuous verification protocols offered by EEGs, eyeblinks may provide a high-level of security when requested in discretized intervals.

An exciting new modality analyzes differences in neural connectomes derived from functional magnetic resonance imaging (fMRI) to identify individuals. Unlike EEGs, fMRI relies on imaging deep neuronal structures, often in a clinical setting. The neural connectome is a diverse, complicated web of linkages among neurons inside the brain, which varies both with experience and genetics. In [35], connectomes constructed in the Human Connectome Project identified persons in a group of 126 persons with high accuracy (approximately 93%). It was noted that analyzing just the frontoparietal network was more distinctive across subjects compared to analyzing the whole brain (p < 10-9), and that these ‘neural fingerprints’ did not change when a person was at rest or performing a task. A person’s fMRI data from one session was used to create a connectivity matrix of their neural connections. This connectivity matrix was then compared to all other connectivity matrices from the remaining sessions, and a correlation coefficient for each session was calculated.

Disadvantages of using fMRI as a biometric is that the subject must remain stationary, it is contraindicated in subjects with implanted metallic devices, and it is significantly more expensive than other methods of biometric verification. However, conclusions drawn on fMRI data are likely to hold true on developing mobile technologies, such as DOT (Diffuse Optical Tomography) [36]. DOT has a greater temporal resolution than fMRI, allowing for continuous verification. However, it may be more dependent on detector placement than EEG [37].

 

Citations:

  1.   Facial movements, eeg authentication using artifacts http://link.springer.com/chapter/10.1007/978-3-319-07995-0_34#page-1
  2.   Multi-level approach based on eye-blinking http://www.sciencedirect.com/science/article/pii/S0167865515002433
  3.   http://www.nature.com/neuro/journal/v18/n11/full/nn.4135.html
  4.   DOI is good  http://www.nature.com/nphoton/journal/v8/n6/full/nphoton.2014.107.html
  5.   DOI vs fMRI – http://www.ncbi.nlm.nih.gov/pubmed/23578579
  6.   http://ieeexplore.ieee.org/xpls/icp.jsp?arnumber=1619442