Direct Current and Magnetic Brain Stimulation for ADHD

Direct Current and Magnetic Brain Stimulation for ADHD

I have been researching new therapies for improving the symptoms of Inattentive ADHD, Sluggish Cognitive Tempo and ADHD. There are several new drugs on the horizon that target our alertness, our neurotransmitters levels, our  histamine levels or our brain oxidation and circulation.  These drugs are all in various stages of development but I have been looking at other treatment modalities as well. One of the more interesting treatments on the horizon is the use of brain stimulation to improve attention, impulsive behavior, hyperactivity, arousal levels and executive function. problems.

Deep brain stimulation, magnetic brain stimulation and electrical current brain stimulation are being tested as treatments for movement disorders and for  mood, memory and executive function problems. Electroconvulsive Therapy or electric shock treatment is a form of brain stimulation that has been used for years to treat psychiatric problems.  How electroconvulsive therapy (ECT) works is still a bit of a mystery but  in major depression ECT  has been found on functional MRI imaging studies to "untangle" brain connections that are hyper connected.  

Deep brain stimulation, electical stimulation and magnetic stimulation, also use currents as therapy but they appear to work in a different way.  Way back in 1985 a researcher by the name of Anthony Barker showed that you could stimulate the brain using magnets and in the process change the electrical activity within the brain in a positive and painless way.  Psychiatrists have found that some patients with mood and behavioral disorders who do not respond to drug therapy, do respond to Transcranial Magnetic stimulation  treatments.  Dr. Barker found that unlike shock therapy, magnetic therapy did not cause negative memory or cognitive side effects.

Transcranial magnetic stimulation therapy and Transcranial direct current stimulation therapy are non-invasive and painless.  These treatments do not require surgery and should not be confused with Deep Brain Stimulation (DBS).  Deep brain stimulation involves placing an electrical pace maker inside the brain. Brain surgery is required  It has been used to treat Parkinson's disease and debilitating Tic disorders such as Tourette's that does not respond to medication. It has not been studied or used, as far as I know, for the treatment of ADHD.

Where tMST uses magnets to stimulate the brain, Trans-cranial direct current stimulation (tDCS) of the prefrontal cortex is a medical procedure that uses a low dose electrical current as a brain treatment. This treatment produces different brain changes from the treatment that uses magnetic stimulation and is potentially a better treatment for ADHD.

Studies have shown that trans magnetic brains stimulation (TMS0 causes nerve cell spikes in the brain area stimulated. How these spikes then affect behavior is now being studied.  Studies on the benefits of magnetic stimulation for the symptoms of ADHD have been mixed..  The results of a study just published in the June edition of the Journal ECT reported no benefits form TMS when compared to placebo for the treatment of ADHD in teens and young adults.  Other studies however have shown that TMS improves attention, at least in the short term.  

One of the problems with studying TMS has been that study subjects know if they are receiving the true treatment vs the placebo.  Somehow they feel or sense the treatment.  In medical study terminology this means that the study cannot be "blinded".  Results from studies that cannot be blinded are always problematic because the knowledge of whether you are or are not in the treatment group may skew the results. 

 Transcranial direct current stimulation may prove to hold the best promise for the treatment of ADHD as initial studies have found it to be helpful for improving working memory and task planning.   Direct current stimulation changes the overall nerve cell electrical activity but does not cause the electrical spikes seen in TMS.  It is thought that the current stimulation changes the integrity of the nerve cell wall and in this way improves the behavior of that nerve cell.  Studies have shown that when you apply a current to the left prefrontal cortex, working memory and task planning improve but at certain times during task performance a positive charge best improves these behaviors while at other times during the same task a negative direction of charge is more effective. Researchers have speculated that the direction of charge is directly related to the amount of dopamine (a neurotransmitter) available at that point in the task.  Other studies have found that impulsive behavior (another dopamine dependent activity) can also be improved with the use of tDCS.  

The idea of a "thinking cap" containing currents that improve our behavior, memory and mood congers up images of the Jetsons.  I imagine that by the time brain stimulation treatments are perfected, there will be all sorts of  gizmos that transmits electrical currents wirelessly  to our brains.  In a few years when we talk to our kids about these treatments they will likely say, "Yea, there's an app for that".

 2012 Jun;28(2):98-103.

Transcranial magnetic stimulation (TMS) in the treatment of attention-deficit/hyperactivity disorder in adolescents and young adults: a pilot study.


Enhancement of selective attention by tDCS: interaction with interference in a Sternberg task.


 2012 May 16. [Epub ahead of print]

Direct current stimulation (tDCS) reveals parietal asymmetry in local/global and salience-based selection.


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