Subject: Teacher check From: Martin Braun <nombraun(at)TELIA.COM> Date: Wed, 2 Mar 2005 13:50:08 +0100Dear Robert, and others: >>Today we have data showing similar signs of appreciation of Mozart's music >>in rats as in humans. > > ...and did you know that they also are avid Dostoevski fans; not to > mention admirers of Velazquez? Good comparison. We do not expect that rats are affected by Dostoevski or Velazquez, but we know that they are affected by music. And you can be certain that there are plenty of more data to come. > Let's just point out two things. First, if it may be useful for people to > look at Kenneth Steele's paper in Music Perception [(2003), 21, p251] in > which he points out that rats' audiograms are such that they are unlikely > to hear anything below 500 HZ, and their cutoff is probably even higher > than that based on the reported SPL of 65 and considering background > noise. So this means that whatever they were hearing, it was Mozart minus > everything below about C5. Music Perception was not the right source then. Rats hear fine at least down to 250 Hz and at least down to 70 dB SPL at this frequency: http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=pubmed&dopt=Abstract&list_uids=893752 http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=pubmed&dopt=Abstract&list_uids=8188553 More importantly, even if their limit was 500 Hz, the rats would easily hear all notes in the Mozart piece. For a long time people could not hear frequencies below 300 Hz on the phone. But on the same phones they could easily follow a male voice down to a pitch corresponding to 50 Hz. (Perhaps the undergraduate that "flunked" your course can tell you the magic ;-)) > The second point, which I would expect an undergraduate to be able to > point out (or else flunk my course), is that the cited study used no > control group other than no treatment. So the specificity of the > conclusions is, shall we say, a bit suspect. Nobody has claimed any specificity in this case. The result was that the rats strongly responded to the presented music. The result was not that they responded differently to this music than to other music. > Sorry to be such a curmugeon. Sorry for the discomfort of facts and reason. Cheers, Martin ---------------------------- Martin Braun Neuroscience of Music S-671 95 Klassbol Sweden web site: http://w1.570.telia.com/~u57011259/index.htm