Edward Fruitman, MD
1451 Broadway
Hewlett, NY 11557
(516) 295-4867

Category

congnition

TMS Could Help Treat Chronic Dizziness

Researchers from the Johns Hopkins University School of Medicine believe that they have located a specific site in the human brain that could be one of the sources of dizziness and spatial disorientation.

While dizziness can also be linked to damage to the inner ear, or to other senses such as vision, neurology instructor Dr. Amir Kheradmand and his colleagues report that they have discovered a region of the brain that plays a vital role in our subconscious awareness of which way is up and which way is down.

Their study, which appears online in the journal Cerebral Cortex, found that some causes of dizziness, unsteadiness and “floating” could be linked to that region in the parietal cortex.

The study authors opted to focus their analysis on the right parietal cortex, as research on stroke victims with balance problems has suggested that damage to that region of the brain was directly involved with upright perception.

They recruited eight healthy subjects, placing each in a dark room and showing them lines that were illuminated on a screen. Dr. Kheradmand’s team then had the study participants report the orientation of each line by rotating a dial to the left, the right, or straight ahead.

The subjects then received (TMS) – an FDA-approved treatment for depression and which “painlessly and noninvasively delivers electromagnetic currents to precise locations in the brain.”

Each individual had a TMS coil placed behind the ear and against the scalp across the right parietal lobe. The subjects received 600 electromagnetic pulses over the course of 40 seconds, and at the end of each session, they were asked a second time to show the researchers which way the illuminated line was positioned. At the end of the study, all of the subjects reported that his or her sense of being upright had been altered in the same way after TMS was administered in the same location in the parietal cortex.

According to Kheradmand, his team’s findings suggest that this form of stimulation could be used to treat chronic dizziness. “If we can disrupt upright perception in healthy people using TMS, it might also be possible to use TMS to fix dysfunction in the same location in people with dizziness and spatial disorientation,” he said.

Magnetic Brain Stimulation — TMS — Can Improve Memory in Schizophrenia

By RICK NAUERT PHD Senior News Editor
Reviewed by John M. Grohol, Psy.D. on March 13, 2013

PsychCentral

Those with schizophrenia are often functionally limited by mental or cognitive impairments.

Memory, attention, IQ, and verbal and motor skills are often disrupted, and these deficits tend to compromise the ability to perform normal day-to-day activities.

Scientists have been exploring a variety of strategies to reduce these impairments, including “exercising the brain” with specially designed computer games and medications that might improve the function of brain circuits.

In a new study, Mera Barr, Ph.D., and her colleagues at University of Toronto provide evidence that stimulating the brain using repetitive transcranial magnetic stimulation (rTMS) may be an effective strategy to improve cognitive function.

“In a randomized controlled trial, we evaluated whether rTMS can improve working memory in schizophrenia,” said Barr and senior author Zafiris Daskalakis, M.D.

“Our results showed that rTMS resulted in a significant improvement in working memory performance relative to baseline.”

Transcranial magnetic stimulation is a non-invasive procedure that uses magnetic fields to stimulate nerve cells. It does not require sedation or anesthesia and so patients remain awake, reclined in a chair, while treatment is administered through coils placed near the forehead.

In 2008, rTMS was FDA-approved to treat depression for individuals who don’t respond to pharmacotherapy.

The study is presented in the journal Biological Psychiatry.

“TMS can have lasting effects on brain circuit function because this approach not only changes the activity of the circuit that is being stimulated, but it also may change the plasticity of that circuit, i.e., the capacity of the circuit to remodel itself functionally and structurally to support cognitive functions,” said Dr. John Krystal, editor of the journal.

Experts say that previous studies have shown that rTMS improves working memory in healthy individuals, and a recent open-label trial showed promising findings for verbal memory in schizophrenia patients.

These findings informed the current study to determine if high frequency rTMS could improve memory in individuals with schizophrenia.

Researchers recruited medicated schizophrenia patients who completed a working memory task before and after 4 weeks of treatment.

Research methodology involved a double-blind study, where neither the patients nor the researchers knew who was receiving real rTMS or a sham treatment that was designed to entirely mimic the procedure without actually delivering brain stimulation.

Investigators discovered TMS not only improved working memory in patients after 4 weeks, but the improvement was to a level comparable to healthy subjects.

These findings suggest that rTMS may be a novel, efficacious, and safe treatment for working memory deficits in schizophrenia.

While the current findings are preliminary, researchers hope additional investigations will replicate the findings and provide an approved treatment for cognitive impairments in schizophrenia.

The authors concluded: “Working memory is an important predictor of functional outcome. Developing novel treatments aimed at improving these deficits may ultimately translate into meaningful changes in the lives of patients suffering from this debilitating disorder.”

TMS Improve Memory in Schizophrenia

Can Repetitive Magnetic Stimulation Improve Cognition in Schizophrenia? Pilot Data from a Randomized Controlled Trial

Mera S. Barr, Faranak Farzan, Tarek K. Rajji, Aristotle N. Voineskos, Daniel M. Blumberger, Tamara Arenovich, Paul B. Fitzgerald, Zafiris J. Daskalakis

Background

Working memory represents a core cognitive domain that is impaired in schizophrenia for which there are currently no satisfactory treatments. Repetitive transcranial magnetic stimulation (rTMS) targeted over the dorsolateral prefrontal cortex has been shown to modulate neurophysiological mechanisms linked to working memory in schizophrenia and improves working memory performance in healthy subjects and might therefore represent a treatment modality for schizophrenia patients. The objectives were to evaluate the effects of rTMS on working memory performance in schizophrenia patients and evaluate whether rTMS normalizes performance to healthy subject levels.

Methods

In a 4-week randomized double-blind sham-controlled pilot study design, 27 medicated schizophrenia patients were tested at the Centre for Addiction and Mental Health (a university teaching hospital that provides psychiatric care to a large urban catchment area and serves as a tertiary referral center for the province of Ontario). Patients performed the verbal working memory n-back task before and after rTMS magnetic resonance image targeted bilaterally sequentially to left and right dorsolateral prefrontal cortex 750 pulses/side at 20 Hz for 20 treatments. The main outcome measure was mean magnitude of change in the n-back accuracy for target responses with active (n=13) or sham (n=12) rTMS treatment course.

Results

The rTMS significantly improved 3-back accuracy for targets compared with placebo sham (Cohen’s d=.92). The improvement in 3-back accuracy was also found to be at a level comparable to healthy subjects.

Conclusions

These pilot data suggest that bilateral rTMS might be a novel, efficacious, and safe treatment for working memory deficits in patients with schizophrenia.