Alzheimer’s disease could soon be treated with a non-invasive therapy that rests magnets on the head to manipulate brain activity, according to new research.
Memory has shown to be improved using a technique that sparks an area of the brain important for sensory skills, scientists in Canada have discovered.
The treatment, called transcranial magnetic stimulation (TMS), involves a portable skull cap that delivers a brief, magnetic pulse through the scalp. It has already shown promise in treating depression, schizophrenia and migraine.
The new finding comes as researchers in Australia are currently carrying out the world’s first trial into the treatment with Alzheimer’s patients. Early reports show that some elderly patients are seeing improvements in their memory and concentration.
In the new study, 17 participants were better at remembering a pattern of tones in reverse after they received TMS.
The study’s author, Dr Philippe Albouy, a cognitive psychologist at McGill University, Montreal, said: ‘Now we know human behaviour can be specifically boosted using stimulation that matched ongoing, self generated brain oscillations.
‘Even more exciting is while this study investigated auditory memory, the same approach can be used for multiple cognitive processes such as vision, perception, and learning.’
These are among the many faculties that can be affected by dementia and the researchers said showing TMS can be used to improve mental performance has clinical implications.
They hope it could eventually compensate for the loss of memory caused by neurodegenerative diseases such as Alzheimer’s.
There are an estimated 850,000 adults in the UK living with dementia, a figure set to rise to two million by 2050 due to an ageing population. Existing drugs simply help symptoms, but their benefits wear off over time and and unfortunately do not work for everyone, resulting in the disease soon taking its devastating course.Co-author Dr Robert Zatorre said: ‘The results are very promising, and offer a pathway for future treatments.
Non-invasive magnet therapy is currently being trialled by Australian researchers to slow the development of Alzheimer’s disease.
Using a new type of transcranial magnetic stimulation (TMS) called theta-burst stimulation, researchers from the Monash Alfred Psychiatry Research Centre (MAPrc) in Melbourne have been able to stimulate nerve cells on the surface of the brain.
Kate Hoy, the MAPrc group leader, said that using theta-burst stimulation allowed a shorter burst of high frequency stimuli to four regions of the brain in three minutes compared to other treatments which took 40 minutes to target one region of the brain.
She said the treatment targeted the build-up of plaque proteins around brain cells which inhibited the ability of those neurons to communicate.
The study is recruiting 100 people with mild to moderate Alzheimer’s aged 50-95 years old to participate in a six-week trial.
‘We plan to do more research to see if we can make the performance boost last longer, and if it works for other kinds of stimuli and tasks.
‘This will help researchers develop clinical applications.’
The participants were given a task that required them to memorise a sequence of tones to the extent that when they were played backwards they could still identify them.
As they did this their brains were scanned using techniques known as MEG (magnetoencephalography) and EEG (electroencephalography), which record magnetic and electric activity in neurons, respectively.
The ability to remember sounds, and manipulate them in our minds, is incredibly important to our daily lives. Without it we would not be able to understand a sentence, or do simple arithmetic.
The new research sheds fresh light on how sound memory works in the brain, and is even shows how to improve it.
Scientists already knew a neural network of the brain called the dorsal stream was responsible for aspects of auditory memory.
Inside this were rhythmic electrical pulses called theta waves, yet the role of these were until recently a complete mystery.
The study, published in Neuron, reveals the precise the relationship between theta waves and auditory memory, and demonstrates how memory could be boosted.
The combination of MEG and EEG revealed the amplitude and frequency signatures of theta waves in the dorsal stream while the subjects worked on the memory tasks. It also showed where the theta waves were coming from.
Using that data, the researchers then applied TMS at the same theta frequency to the subjects while they performed the same tasks, to enhance the brain waves and measure the effect on memory performance. They found that when they applied TMS, subjects performed better.This was only the case when the TMS matched the rhythm of natural theta waves in the brain. When the TMS was arrhythmic, there was no effect on performance. This suggested it was the manipulation of the theta waves, not simply the application of TMS, which improved performance.
Another co-author of the study Professor Sylvain Baillet explained: ‘For a long time the role of theta waves has been unclear.
‘We now know much more about the nature of the mechanisms involved and their causal role in brain functions.’The findings follows US research three years ago that found TMS led to improvement in memory that lasted for 24 hours.
That team said the technique could lead to non-pharmaceutical treatments for memory disorders resulting from disease, injury and even ageing.
They used MRI (magnetic resonance imaging) scanning to identify a brain region just a centimetre from the surface of the brain which was closely connected to the hippocampus, which controls memory.
When TMS was applied there, activity in the associated regions became better synchronised.
The next day participants who received TMS were much better at remembering associations between human faces and words than those receiving a placebo stimulus.
A new study has shown that memory was improved after participants received transcranial magnetic stimulation (TMS) b-error
Researchers are attempting to alleviate the symptoms of Alzheimer’s, a disease in which proteins build up in the brain to form ‘plaques’ and ‘tangles’ which lead to the loss of connections between nerve cells and eventually loss of brain tissue
Magnets could delay the progression of Alzheimer’s, which causes memory difficulties and problems with thinking, reasoning, perception or communication