Transcranial Magnetic Stimulation May Calm Symptoms

A form of brain stimulation holds promise for treating aspects of autism

Brain Scan
Brain Scan. Don Farrall

Researcher Says He Has "Found the Pathology of Autism"

Dr. Manuel Casanova holds an endowed chair at the University of Kentucky. He's written dozens of peer-reviewed papers, and receives funding from the National Institutes of Health. Dr. Casanova is conducting research on the autistic brain -- and, according to him: "I think we have found the pathology of autism. ...It explains so much, it all makes sense."

Not only does Dr. Casanova believe he has found the pathology of autism, but he is also working on a treatment which may have the ability to lessen autistic symptoms of hypersensitivity without compromising the creativity and savant abilities that make autistic people so extraordinary.

Minicolumns in the Autistic Brain: Good News and Bad News

The outer part of the brain is called the neocortex. Within the neocortex are groups of cells called minicolumns. These minicolumns are the smallest unit of cells capable of processing information. Ordinarily, minicolumns include relatively large cells, called neurons, which allow communication not only within an individual minicolumn but also among different parts of the brain.

Minicolumns in people with autism are smaller and more numerous than normal. In addition, neurons within each minicolumn are reduced in size. This may be both good and bad, says Casanova: "Since the efficiency of connections among neurons is a function of cell size, the presence of smaller neurons in the brains of autistic patients has a dramatic effect on the way that different parts of the brain interact with each other.

Brain activities that require longer projections (e.g., language) may be impaired while those that depend on shorter connections (e.g., mathematical manipulations) may be preserved or reinforced."

In other words, people with autism are exceptionally good at anything that can be processed in one area of the brain -- such as math and visual discrimination.

They are, however, exceptionally bad at anything that requires coordination among various parts of the brain -- such as social skills, language, and face discrimination.

Bad Insulation Between Minicolumns May Cause Sensory Issues

According to Casanova, one side effect of extra minicolumns with extra-small cells is "stimuli are no longer contained within specific minicolumns but rather overflow to adjacent minicolumns thus providing an amplifier effect. This may explain the hypersensitivity of some autistic patients as well as their seizures."

Casanova likens this to water contained in a shower. "The inhibitory fibers act in analogous fashion to a shower curtain. When working properly and fully draping the bathtub the shower curtain prevents water from spilling to the floor." People with autism have leaky shower curtains.

Increasing Insulation Could Lessen Sensory Issues and Seizures Without Compromising Creativity

Dr. Casanova believes that it is possible to increase the "insulation" surrounding minicolumns, thus lessening sensory overload and the likelihood of seizures.

The beauty of his theory is, these negative outcomes could be addressed WITHOUT impacting the ability of people with autism to think, perceive and create outside the box.

Here's how it works: According to Casanova, the "main property of these [minicolumn] cells and projections is that they stand at 90 degrees to surface of the cortex. They are the only cells that do so." Casanova theorizes that transcranial magnetic stimulation (TMS) could "flip the magnetic field in the cortex," thus reinforcing the insulation around the minicolumns. This treatment would (according to existing research) have minimal side effect. Most importantly, it would not have the side effect of changing the personality or thought processes of the person being treated.

Could TMS Be the "Real Deal?"

This idea is not as odd as it may sound. In fact, TMS has already proved useful in treating mental illnesses such as schizophrenia and depression. Clinical trials are in progress through the NIH to test the usefulness of TMS in treating hallucinatory voices. Over the course of several years, various organizations have undertaken trials of TMS -- but so far there is no consensus on the results. While trials at Harvard and elsewhere seem to hold promise, and articles in publications such as Newsweek are positive, TMS remains a fringe therapy that is not yet ready for general use.


Telephone interview with Dr. Manuel Casanova. September, 2006.

Casanova MF, Kooten IAJ van, Switala AE, Engeland H van, Heinsen H, Steinbusch HWM, Hof PR, Schmitz C. Abnormalities of cortical minicolumnar organization in the prefrontal lobes of autistic patients. Clinical Neuroscience Research 2006; 6(3–4), 127–133.

Casanova MF, Kooten IAJ van, Switala AE, Engeland H van, Heinsen H, Steinbusch HWM, Hof PR, Trippe J, Stone J, Schmitz C. Minicolumnar abnormalities in autism. Acta Neuropathologica 2006; 112(3), 287–303.

Casanova MF, Abnormalities Of Cortical Circuitry In The Brains Of Autistic Individuals. Presented at the All Wales Autism Resource (AWARES) International Conference, 2006.

Chae, J. H., Nahas, Z., Wassermann, E., Li, X., Sethuraman, G., Gilbert, D., et al. (2004). A pilot safety study of repetitive transcranial magnetic stimulation (rTMS) in Tourette's syndrome. Cognitive and Behavioural Neurology, 17(2), 109-117.

Mantovani, A., Lisanby, S. H., Pieraccini, F., Ulivelli, M., Castrogiovanni, P., & Rossi, S. (2006). Repetitive transcranial magnetic stimulation (rTMS) in the treatment of obsessive-compulsive disorder (OCD) and Tourette's syndrome (TS). International Journal of Neuropsychopharmacology, 9(1), 95-100.

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