slumber#2

動物は夢を見るかどうかという研究を取り上げた記事です。あらゆる生物が睡眠を行うということは確認されているそうです。しかし，人間以外の生物は夢を見るのでしょうか。いろいろな実験結果から答えはyesであるそうです。
　この記事の中で気になった表現は"slumber"です。『Wisdom第三版（三省堂）』にようると「眠る，まどろむ，休眠」などという意味がありました。記事の中には他にも"snooze"という表現もあります。これは「うたた寝をする，居眠りをする」という意味です。以前のブログで詳しく書かれておりますのであわせてご確認ください。(Ume)

What do animals dream about?

Physical movement is not the only way of peering into dreams, though. Researchers can now humanely peer into the electrical and chemical activities of brain cells in animals while they sleep. In 2007, MIT scientists Kenway Louise and Matthew Wilson recorded the activity of neurons in a part of the rat brain called the hippocampus, a structure known to be involved in the formation and encoding of memories. They first recorded the activity of those brain cells while the rats ran in their mazes. Then they looked at the activity of the very same neurons while they slept. Louise and Wilson discovered identical patterns of firing during running and during REM. In other words, it was as if the rats were running the maze in their minds while they were snoozing. The results were so clear that the researchers could infer the rats' precise location within their mental dream mazes and map them to actual spots within the actual maze.

University of Chicago biologists Amish Dave and Daniel Margoliash looked into the brains of zebra finches and discovered something similar. These birds are not born with the melodies of their songs hardwired into the brains; instead, they have to learn to sing their songs. When they're awake, the neurons in part of the finches' forebrain called the robutus archistriatalis fire following their singing of particular notes. Researchers can determine which note was sung based on the firing patterns of those neurons. By piecing together the electrical patterns in those neurons over time, Dave and Margoliash can reconstruct the entire song from start to finish.

Later, when the birds were asleep, Dave and Margoliash looked again at the electrical activity in that part of their brains. The firing of those neurons wasn't entirely random. Instead, the neurons fired in order, as if the bird was audibly singing the song, note for note. It might be said that the zebra finches were practising their songs while they slumbered.

http://www.bbc.com/future/story/20140425-what-do-animals-dream-about

afternoon slumber - 田邉祐司ゼミ 常時英心：言葉の森から
snooze - 田邉祐司ゼミ 常時英心：言葉の森から