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Nevertheless, few patients did show memory improvements. These were the same two who reported memory recollections when the electrodes were first implanted.

Lately, we were researching about electrical stimulation of the hippocampus. Some experts said that it causes temporary amnesia – Zapping Memories Away.
It all started when Toronto experimental treatment centers started using deep brain stimulation (DBS) to improve memory in people with Alzheimer’s disease. Progressive loss of memory is the main symptom of this disorder, and while some drugs are available, they provide partial relief or even less than that.
But recently lucky a chance discovery by the same Toronto group shown us new direction. In 2008, they reported that stimulation of the hypothalamus caused vivid memory recollections for a 40-year-old man. In that case, the effect was entirely unintended and unexpected. The patient was being given DBS to try to curb his appetite (he weighed 350 pounds.)
And though the hypothalamus is involved in regulating appetite, not memory – but the fornix, a nerve bundle that passes through that area, is. It’s the main "nerve highway" connecting the hippocampus to the rest of the brain, and the hippocampus is vital for memory.