A study of the visual evoked magnetic field related to memory function by using a 320-channel MEG system

摘要

We are studying how to find the early stages of dementia, such as Alzheimer's disease (AD), by using a MEG system, In relation to brain functions and dementia, memory defects are characterized as the most obvious signs of dementia. In a preliminary study, we tried to measure the visual evoked magnetic field related to memory function by using a simple memory task. In the memory task measurement, the subject memorized one figure for a few seconds, and then counted the number of memorized figures that appeared in the sequence of figures presented randomly. Evoked responses by visual stimuli were averaged for each condition. We compared the results of the control and memory task and identified the components, which seem to be related to memory functions.