A collaborative research team led by Professor Kazuto Kobayashi of Fukushima Medical University and Professor Shogo Sakata of Hiroshima University succeeded in removing specific nerve cells in the basal forebrain of the brain, resulting in the location and objects of objects. It was clarified that the memory ability related to itself is reduced.It was known that these cells were lost in Alzheimer's disease, but this is the first time we have shown how they are involved in memory capacity.
As Alzheimer's disease progresses, nerves degenerate and severe memory impairment occurs.In particular, as an initial symptom, a disorder of recognition memory that reminds us of what we once saw or where we visited appears prominently.At this time, it is known that among nerve cells, acetylcholine nerve cells die, but it was not known how these cells are involved in recognition memory.To investigate this, we first created two types of mice from which acetylcholine neurons located in the medial septum and the Nucleus basalis were separately removed.By conducting a memory test on this mouse, we investigated the role of two types of acetylcholine neurons.The test examined whether the object itself and its position that were seen in the past are remembered.As a result of this test, the mouse with the damaged medial septum remembered the object itself, but did not remember the position of the object.We also found that mice with damaged Nucleus basalis remembered the position of the object, but not the object.Furthermore, it was found that these recognition memory disorders can be recovered by administering drugs used to treat dementia.
The role of acetylcholine neurons revealed in this study will be a great clue to elucidate the mechanism of recognition memory impairment.It also paved the way for drugs to alleviate the memory impairment caused by the death of acetylcholine neurons.
