Cortical Chauvinism

Switched On

NOTE: During the past few months I have been made aware that the link buttons at the end of my blogs do not provide a proper count for those who have shared the same through social media. I appreciate people emailing me about the problem; however, I am computer naïve and do not know how to correct the problem. Sorry

Switched On is the long awaited book of John Elder Robison’s personal experiences with Transcranial Magnetic Stimulation (TMS). John is a very talented individual within the autism spectrum who has been quite successful while partaking in diverse careers, e.g., guitar engineer, car mechanic, photographer. In the world of autism John is best known as both an author (Look Me in the Eyes) and Neurodiversity advocate. It is difficult to attend an autism related activity without his name being mentioned.

John has taken a “soft stance” on Neurodiversity, one that sees both gifts and disabilities for those within the spectrum while also accepting the benefits of research and therapy. The “hard stance” for other Neurodiversity individuals is that autism (and other mental conditions) falls within the normal variability of the human genome and thus, being normal, see no need for further research or treatment.

The book Switched On relates how sometime in 2008 John partook in a research study on TMS and autism directed by Alvaro Pascual-Leone from Harvard University. After one session of stimulations John felt an emotional upsurge that allowed him to perceive the world around him differently to what he was accustomed. His description suggests that TMS opened a floodgate of introspective thoughts as to his own emotional state and the people around him. He recalled past memories that seemingly persisted in his subconscious and now –after TMS- acquired a different meaning. According to John these changes have persisted and may account for some of the emotional highs and lows he has experienced over the last few years. On the positive side, as a photographer his compositions have acquired an individual artistic style that he and others seem to enjoy. John has also become more empathetic towards the plight of his customers as they bring their cars to his repair shop. Furthermore, his social skills have remarkably improved, especially in regards to the art of “small-talk”. On the negative side, John believes TMS made him more aware of the problems in his marriage and ultimately contributed to his divorce.

Transcranial Magnetic Stimulation is a technique that induces a current in a small area of the cerebral cortex. The equipment works in analogous fashion to an electrical generator where a changing magnetic field induces current in a wire. In the case of the brain, the machine (generator) provides the magnetic field and the wires are the projections of cells called neurons. A different technique called transcranial direct current stimulation uses a small amount of current (1-2 miliamperes) between scalp electrodes to change the state of brain activation.  In some chapter towards the end of Switched On TMS and tDCS are conflated.

The circuitry of tDCS is quite simple and can be easily assembled by the do-it-yourself community. I have questioned whether this technique is of any benefit and those using the same appear to lack sophistication in both electronics and neurosciences (see bit.ly/1P8Brqx). I usually say that the naivety of neuroscientists will be judged by the number of tDCS articles in their CVs. At present tDCS providers are targeting desperate parents of children with neurodevelopmental conditions and charging them money for therapies that have yet to be validated. TMS on the other hand depends on the discharge of a large current from a bank of supercapacitors into a coiled wire. The high current is very dangerous and requires the use of special switches and “bleeding” components. The circuitry required for TMS escapes the knowledge of the do-it-yourself community.

Switched On narrates the emotional liberation of John that occurred after TMS. However, an equally impressive story (in essence a subplot) is the lack of ethics of the people that conducted the TMS clinical trial wherein John participated. For purpose of the trial John helped recruit patients through his blog. John also gave lectures and narrated his personal observations that then became available to potential participants.  Moreover, the administrators of the trial instigated John to share his experiences with other participants and eventually altered the negative perspective of at least one of them. Later on John and other participants were recycled into other TMS trials. In one part of the book it is suggested that John may have participated simultaneously in more than one study. These patients were no longer naïve and their brains had already been changed by the initial bout of TMS stimulation. The results of these trials are tainted.

John’s trial was finally published in a third tier journal in 2011. The same provided results on a small population, only 10 patients. The study was not a treatment trial but one studying brain mechanisms engaging the formulation of words (object naming). The reasoning behind the experiment was never properly formulated and John recounts multiple sessions where the ideas ricocheted from corpus callosum projections to emotional reciprocity to mirror neurons.  At present the idea of a broken mirror system in autism has been debunked (see bit.ly/1M9F84T). Furthermore it is extremely naïve from a neurosciences perspective to take mirror neurons as the basis of a TMS experiment. Mirror neurons only constitute a minority of the cells at any given site.  Even when the proper site and depth can be stimulated any effects of TMS would be the result of the large majority of non-mirror neurons being activated (note: some of these cells have an anti-mirror neuron effect).

I personally take exception at the way the investigators changed experimental parameters from their first trial to those conducted more recently, and for which patients have apparently been recycled.  John participated and had good results with slow frequency stimulation but was bothered and claimed no similar beneficial effects from later interventions in which a very fast rate of stimulation (theta burst) was used. Theta bursts may shorten the time of stimulation from half an hour (with slow frequency) to only a couple of minutes. The shortened time is advantageous to the physician; however, a side-by-side comparison trial in ASD should have been attempted before completely shifting parameters. When dealing with patients, it is all about baby steps.

My group finished a treatment clinical trial on TMS and ASD in 2005 and was able to publish the results in the Journal of Autism and Developmental Disorders 3 years later. By 2008 we had concluded 2 additional trials and had already treated over 100 individuals in the autism spectrum.  More importantly the people at Harvard had a copy of our grant and preliminary results. Our next 2 studies were published in 2010. In all we have seen and reported on more patients than all other groups combined. Contrary to Harvard my group has concentrated on treatment efforts rather than studying potential mechanisms. We have reported beneficial reports on TMS and ASD but only in higher functioning individuals. One of my biggest regrets has been telling parents of lower functioning individuals that their child may not be able to participate in our trials as they may not comply with inclusionary/exclusionary criteria. This practice of warning patients has escalated  after Switched On was published.

I am extremely happy for the life altering experience that John has had. In addition publicizing his story has certainly brought a lot of needed publicity to the field. We conceived of TMS as being the first therapeutic intervention targeting the core pathology of the condition. Side effects are minimal. However, results vary from individual to individual. I have never seen results of the magnitude reported by John and they certainly have not been apparent immediately after stimulation.  TMS effects are cumulative and the brain has to remodel itself based on the magnetic pulses, a process that takes time. What I would try to avoid is having parents gain false hope and be the targets of unscrupulous commercial ventures targeting both their plight and pockets (see bit.ly/1qq6ytg).