Insight, a growth project driven by tDCS: Simple DIY TDCS circuit using CRDs

 Read the full article here.

Above is a schematic for a simple tDCS circuit that will supply 1mA. The CRD (E-102) maintains a 1mA regulated current to the head (between the Anode and Cathode). The E-102 can be purchased at www.mouser.com. Two 9V batteries are better than one, particularly if you have a less than perfect electrode-head interface, and it will last much longer without the need to change the battery; also the CRD has a 1V-2V drop so the full battery voltage is not present at the Anode. In using the CRD, you have a two pin regulator instead of a three pin regulator and a resistor for the LM334, which means simpler construction.

via Insight, a growth project driven by tDCS: Simple DIY TDCS circuit using CRDs.

The Hidden Costs of Cognitive Enhancement | Wired Science

And the link to the full paper. The Mental Cost of Cognitive Enhancement (HatTip ComradeSergey)

Those who had the parietal area involved in numerical cognition stimulated learned the new number system more quickly than those who got sham stimulation, the researchers report today in the Journal of Neuroscience. But at the end of the weeklong study their reaction times were slower when they had to put their newfound knowledge to use to solve a new task that they hadn’t seen during the training sessions. ”They had trouble accessing what they’d learned,” Cohen Kadosh said.

The volunteers who had the prefrontal area involved in learning and memory stimulated showed the opposite pattern. They were slower than the control group to learn the new numerical system, but they performed faster on the new test at the end of the experiment. The bottom line, says Cohen Kadosh, is that stimulating either brain region had both benefits and drawbacks. ”Just like with drugs, there seem to be side effects,” he said.

via The Hidden Costs of Cognitive Enhancement | Wired Science | Wired.com.
See Also: Brain-Boosting Technique Might Help Some Functions While Hurting Others

Michael Weisend – Mind Research Network DIYtDCS Podcast #4

Dr. Michael WeisendMichael Weisend PHD. is a principal investigator at The Mind Research Network, MRN.org, and assistant professor of Translational Neuroscience at the University of New Mexico, Albuquerque. Dr. Weisend and his team pioneered a method for determining optimal brain regions for tDCS stimulation using fMRI. Much of Dr. Weisend’s work is focused on cognitive enhancement in healthy subjects for the purpose of reducing the amount of time it takes to master a skill. He shared a full hour of his time and a wealth of tDCS-related information. Download the interview here (zipped mp3). Subscribe in iTunes. (Firefox users- there’s an issue with the html5 audio player. In the meantime you can download the episode or open the page in another browser).

Show Notes
The Sally Adee article I discuss. (pdf)
The Through The Wormhole episode mentioned. (YouTube)
Magnetoencephalography
DARPA The Defense Advanced Research Projects Agency
DARWARS Ambush NK is a research program intended to accelerate the development and deployment of military training systems. (wiki) (pdf)
TDCS guided using fMRI significantly accelerates learning to identify concealed objects.
eeg electrodes + gel + wrap.
Transcranial direct current stimulation’s effect on novice versus experienced learning.
iNTIFIC Develops games and training.
pulsed oscillatory electromagnetic fields
tRNS
Fisher Wallace Stimulator.
Perils of tDCS.
F10-anodal, cathodal-opposite upper arm, actually does something.
‘Target search and identification’. What could it be good for the average person?
Dear reader, help me find a way to build a self-experiment that will test my results.
Recalling distant memories?
Anecdotes…
Girl who heard melodies.
Guy who solved a problem he’d been working on.
Age-related memory decline… ‘I can find words now…’
-More verbally fluent as a result of tDCS
-Left Inferior Frontal Gyrus (approx F5-anode, cathode opposite upper arm)
“People do not like it.” Cathodal stimulation of F10
Accelerating non-declarative skill learning.
-Cathode-L-DLPFC, Anode-M1
Grants outstanding to test more of this.
Recruiting the correct brain network to deal with the stimuli at hand for the purpose of successful task completion.
Competing brain networks!
Neural modulation fastest growing area of medicine.
Ethics of tDCS.
Lisa Marshall
Potential for-profit applications?
Conferences: Human Brain Mapping, Seattle June 16-20
Society for Neuroscience San Diego Nov 9-13

tDCS – Building a Resistor Based tDCS Device

Brent Williams of SpeakWisdom (we met him earlier on the blog) has started a YouTube tDCS series. This is his second in the series. This is an excellent overview of the basic components of tDCS, however, Brent does not recommend you actually build
and use a resistor-based device. Brent mentions that upcoming videos will demonstrate how to build a current-regulated device.

February 2013 tDCS Papers of Interest

If there’s no link to a pdf, it means the full paper is behind a paywall. If you find a public link to the full paper, please send it along and I’ll update the post. Did I miss anything 😉
Bold: Paper title, linked to Abstract
(pdf): Direct pdf download where available
Italic: ‘Takeaway’ snippet from abstract.
(Bracketed): My thoughts FWIW
Tags:

Transcranial direct current stimulation increases resting state interhemispheric connectivity.
the tDCS group showed increased DLPFC connectivity to the right hemisphere and decreased DLPFC connectivity to the brain regions around the stimulation site in the left hemisphere. (Lends more credence to the idea of increasing positive effects of tDCS by simultaneously damping down (cathodal) and ramping up (anodal) neuronal activity.)
Tags: theory, learning, enhancement

Transcranial direct current stimulation for treatment of refractory childhood focal epilepsy.
A single session of cathodal tDCS improves epileptic EEG abnormalities for 48 h and is well-tolerated in children.
Tags: epilepsy, children

Brain stimulation modulates the autonomic nervous system, rating of perceived exertion and performance during maximal exercise.
…indicating that the brain plays a crucial role in the exercise performance regulation.
Tags: sports medicine

Evolution of Premotor Cortical Excitability after Cathodal Inhibition of the Primary Motor Cortex: A Sham-Controlled Serial Navigated TMS Study (pdf)
Cathodal inhibition of M1 excitability leads to a compensatory increase of ipsilateral PMC (premotor cortical regions) excitability. (Cathodal tDCS used as a tool to facilitate an experiment)
Tags: theory,

Rethinking Clinical Trials of Transcranial Direct Current Stimulation: Participant and Assessor Blinding Is Inadequate at Intensities of 2mA (pdf) (See also: A big hole in the control? Transcranial direct current stimulation blinding on trial)
Our results suggest that blinding in studies using tDCS at intensities of 2 mA is inadequate. Positive results from such studies should be interpreted with caution.
Tags: theory, sham, blinding,

The effects of cross-hemispheric dorsolateral prefrontal cortex transcranial direct current stimulation (tDCS) on task switching
Task switching, defined as the ability to flexibly switch between tasks in the face of goal shifting, is a central mechanism in cognitive control. …Our findings confirm the notion that involvement of the PFC on task switching depends critically on laterality, implying the existence of different roles for the left hemisphere and the right hemisphere in task switching.
Tags: task switching, theory

The role of timing in the induction of neuromodulation in perceptual learning by transcranial electric stimulation
tRNS (transcranial random noise stimulation) facilitated task performance only when it was applied during task execution, whereas anodal tDCS induced a larger facilitation if it was applied before task execution. (This study showed tDCS to be more effective when applied prior to training! (i.e. ‘offline’)
Tags: tRNS, offliine, online, training, enhancement, perceptual learning

Modulation of verbal fluency networks by transcranial direct current stimulation (tDCS) in Parkinson’s disease
…left dorsolateral prefrontal cortex (DLPFC) tDCS increased performance on the phonemic fluency task
Tags: Parkinson’s, verbal fluency

Transcranial Electrical Currents to Probe EEG Brain Rhythms and Memory Consolidation during Sleep in Humans (2011) (pdf)
…results demonstrate the suitability of oscillating-tDCS as a tool to analyze functions of endogenous EEG rhythms and underlying endogenous electric fields as well as the interactions between EEG rhythms of different frequencies. (Way over my head at this point but trying to understand it, as Lisa Marshall is frequently mentioned in discussions around tDCS and memory. I’m also trying to build an understanding of EEG.)
Tags: memory consolidation, EEG, theory

(pdf) Random Noise Stimulation Improves Neuroplasticity in Perceptual Learning (2011)
Our results confirmed the efficacy of hf-tRNS over the visual cortex in improving behavioral performance and showed its superiority in comparison to other TES. (tRNS transcranial random noise stimulation, has been showing up more often in relation to studies focused on learning and cognition.)
Tags: tRNS, perceptual learning, neural plasticity,

Focal Modulation of the Primary Motor Cortex in Fibromyalgia Using 4×1-Ring High-Definition Transcranial Direct Current Stimulation (HD-tDCS): Immediate and Delayed Analgesic Effects of Cathodal and Anodal Stimulation
4×1-ring HD-tDCS, a novel noninvasive brain stimulation technique capable of more focal and targeted stimulation, provides significant reduction in overall perceived pain in fibromyalgia patients..
Tags: HD-tDCS, Fibromyalgia, pain health

Transcranial direct current stimulation’s effect on novice versus experienced learning (2011)
TDCS was significantly more effective in enhancing test performance when applied in novice learners than in experienced learners.
Tags: learning, threat detection, anode F8,

Evaluation of sham transcranial direct current stimulation for randomized, placebo-controlled clinical trials.
The tDCS sham condition investigated here may be suitable for placebo-controlled trials keeping subjects blind to treatment conditions. (The protocol for sham tDCS is necessarily evolving.)
Tags: sham,

Tremor Suppression by Rhythmic Transcranial Current Stimulation
With this technique we can achieve almost 50% average reduction in resting tremor amplitude and in so doing form the basis of a closed-loop tremor-suppression therapy that could be extended to other oscillopathies. (tACS transcranial alternating current)
Tags: Parkinsons, tremor, tACS

Is Transcranial Alternating Current Stimulation Effective in Modulating Brain Oscillations? (pdf)
Therefore, the present study does not provide significant evidence for tACS reliably inducing direct modulations of brain oscillations that can influence performance in a visual task.
Tags: tACS, posterior parietal cortex, visual perception

Neuromodulation for Brain Disorders: Challenges and Opportunities (pdf)
This article reviews the state-of-the-art of neuromodulation for brain disorders and discusses the challenges and opportunities available for clinicians and researchers interested in advancing neuromodulation therapies. (Excellent overview of where we’re at with various forms of brain stimulation)
Tags: Neuromodulation, brain stimulation, tDCS, DBS (Deep Brain Stimulation), ICS (intracranial cortical stimulation), TMS (transcranial magnetic stimulation)

Improved proper name recall in aging after electrical stimulation of the anterior temporal lobes (2011) (pdf)
The task was to look at pictures of famous faces or landmarks and verbally recall the associated proper name. Our results show a numerical improvement in face naming after left or right ATL stimulation, but a statistically significant effect only after left-lateralized stimulation.
Tags: name recall, anterior temporal lobes, aging,

Transcranial brain stimulation (not sure this link will work for you pdf)
This book reviews recent advances made in the field of brain stimulation techniques. Moreover NIBS techniques exert their effects on neuronal state through different mechanisms at cellular and functional level.
Tags: NIBS (non-invasive brains stimulation), research overview,

Naming facilitation induced by transcranial direct current stimulation. (2010)
…anodal tDCS of the left DLPFC improves naming performance, speeding up verbal reaction times after the end of the stimulation, whereas cathodal stimulation had no effect.
Tags: learning, left DLPFC,

Consolidation of Human Motor Cortical Neuroplasticity by D-Cycloserine (2004) (pdf)
While anodal tDCS enhances motor cortical excitability, cathodal tDCS diminishes it. Both effects seem to be NMDA receptor dependent. D-CYC selectively potentiated the duration of motor cortical excitability enhancements induced by anodal tDCS.(Again, way over my head, but NMDA receptors comes up frequently in the context of tDCS and neurotransmitters.)
Tags: NMDA receptors, D-Cycloserine, learning, enhancement

Interactions between transcranial direct current stimulation (tDCS) and pharmacological interventions in the Major Depressive Episode: Findings from a naturalistic study. (See also: Electrical Brain Stimulation Plus Drug Fights Depression)
…To investigate the interactions between tDCS and drug therapy …tDCS over the DLPFC acutely improved depressive symptoms.
Tags: depression, Zoloft

Physiological and modeling evidence for focal transcranial electrical brain stimulation in humans: A basis for high-definition tDCS.
We provide direct evidence in humans that TES with a 4 × 1-Ring configuration can activate motor cortex and that current does not substantially spread outside the stimulation area.
Tags: HD-tDCS, electrodes, M1

Transcranial Direct Current Stimulation (tDCS) Reduces Postsurgical Opioid Consumption in Total Knee Arthroplasty (TKA).
…tDCS may be able to reduce post-TKA opioid requirements.
Tags: pain,

Modulating lexical and semantic processing by transcranial direct current stimulation.…(tDCS), which is applied over Wernicke’s area and its right homologue, to influence lexical decisions and semantic priming…
Results showed impaired lexical processing under right anodal/left cathodal stimulation in comparison with sham and left anodal/right cathodal stimulation.