[A version of this item appears in: Dementia: the Latest Evidence Newsletter (RWHT), Volume 2 Issue 5, December 2011].
Alzheimer’s Disease could be eased by regular small fleeting pulses of electricity. A small safety trial to test “deep brain stimulation” (DBS) in six patients with Alzheimer’s Disease using surgically implanting electrodes found that some patients showed slight improvements.
A preliminary and small-scale clinical study examined the effect of deep brain stimulation (DBS) on the size and functioning of the hypothalamus, which is involved in memory, to see whether stimulating this area of the brain might alter the memory circuits in patients with early Alzheimer’s Disease. They measured changes in the activity of brain structures, the brain’s use of sugar (which is typically reduced in patients with Alzheimer’s) and cognitive function after 1, 6 and 12 months.
Two of the six participants showed a less severe decline in functioning than expected, one had a more severe decline, and three had a similar change in functioning as expected. In addition to the areas stimulated by DBS directly, other regions involved with in memory circuitry were activated consistently in all six patients. Stimulation of the hypothalamus apparently drives the activity of the brain’s memory circuits. After 1 and 12 months of DBS, all six patients had increased activity in the brain areas affected by Alzheimer’s Disease. The researchers claim that deep brain stimulation (DBS) produces “striking and sustained changes” and that the technique is safe.
A follow-up study in mice showed that DBS resulted in the generation of new cells in the hippocampus (another part of the brain involved in memory). The original human trial appeared in the Annals of Neurology, and a follow-up mouse study appeared in the Journal of Neuroscience.
The researchers are now conducting larger human trials and animal research to determine the potential of DBS as a treatment for Alzheimer’s Disease.
Note: The mild electrical stimulation in DBS should not to be confused with electroconvulsive shock therapy (ECT).
Note: This study lacked a control group so it isn’t yet possible to prove any slowing in the deterioration expected in people with Alzheimer’s as a direct result of DBS treatment.
Note: The patients involved in this study were all in the early stage of the disease, so use of this therapy in patients with more advanced disease may not be suitable. Further, this type of surgery could be distressing or confusing for people with dementia. Invasive brain surgery may be unsuitable for frail elderly patients due to age-related complications and counter-indications.
Brain electric shocks used to treat Alzheimer’s. London: NHS Choices, November 25th 2011.
Stone, SS. Teixeira, CM. [and] Devito, LM. [et al] (2011). Stimulation of entorhinal cortex promotes adult neurogenesis and facilitates spatial memory. The Journal of Neuroscience : the official journal of the Society for Neuroscience, September 21st 2011, Vol.31(38), pp.13469-84. (Click here to view the PubMed abstract).
Laxton, AW. Tang-Wai, DF. [and] McAndrews, MP. [et al] (2010). A phase I trial of deep brain stimulation of memory circuits in Alzheimer’s disease. Annals of neurology, October 2010, Vol.68(4), pp.521-34. (Click here to view the PubMed abstract).