Subject: pressure-induced pitch shifts From: William Hartmann <hartmann(at)PA.MSU.EDU> Date: Wed, 21 Nov 2001 12:58:13 -0500This is a multi-part message in MIME format. ------=_NextPart_000_00D2_01C1728C.2E1069A0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable Dear List, On the New Scientist question. The yawning effect on pitch may be = related to the pitch shift observed on clenching the jaw, reported by Corey JASA 22, = 640 (1950). It seems possible that these pitch shifts are the result of intensity = changes and the pitch-intensity effect, but they don't sound that way. An alternative = explanation would be that pressure on the oval (or round) window biases the basilar = membrane a little so that the place of maximum excitation shifts slightly. Then the place = theory of pitch perception would predict a pitch shift.=20 Another way to get pitch shifts is to bias the basilar membrane with = a very low- frequency tone (as in a masking period pattern experiment) and observe = the pitch=20 of a high-frequency tone presented in the peaks or the valleys of the = low-frequency=20 tone. Hope to see you all at ASA Fort Lauderdale in a few weeks! Best wishes, Bill Hartmann ------=_NextPart_000_00D2_01C1728C.2E1069A0 Content-Type: text/html; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable <!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN"> <HTML><HEAD> <META http-equiv=3DContent-Type content=3D"text/html; = charset=3Diso-8859-1"> <META content=3D"MSHTML 5.50.4611.1300" name=3DGENERATOR> <STYLE></STYLE> </HEAD> <BODY bgColor=3D#ffffff> <DIV><FONT size=3D2>Dear List,</FONT></DIV> <DIV><FONT size=3D2></FONT> </DIV> <DIV><FONT size=3D2> On the New Scientist question. = The yawning=20 effect on pitch may be related to the</FONT></DIV> <DIV><FONT size=3D2>pitch shift observed on clenching the jaw, reported = by Corey=20 JASA 22, 640 (1950).</FONT></DIV> <DIV><FONT size=3D2></FONT> </DIV> <DIV><FONT size=3D2>It seems possible that these pitch shifts are the = result of=20 intensity changes and the</FONT></DIV> <DIV><FONT size=3D2>pitch-intensity effect, but they don't sound that = way. An=20 alternative explanation would</FONT></DIV> <DIV><FONT size=3D2>be that pressure on the oval (or round) window = biases the=20 basilar membrane a little</FONT></DIV> <DIV><FONT size=3D2>so that the place of maximum excitation shifts = slightly. Then=20 the place theory of</FONT></DIV> <DIV><FONT size=3D2>pitch perception would predict a pitch shift. = </FONT></DIV> <DIV><FONT size=3D2></FONT> </DIV> <DIV><FONT size=3D2> Another way to get pitch shifts = is to bias=20 the basilar membrane with a very low-</FONT></DIV> <DIV><FONT size=3D2>frequency tone (as in a masking period pattern=20 experiment) and observe the pitch </FONT></DIV> <DIV><FONT size=3D2>of a high-frequency tone presented in the = </FONT><FONT=20 size=3D2>peaks or the valleys of the low-frequency </FONT></DIV> <DIV><FONT size=3D2>tone.</FONT></DIV> <DIV><FONT size=3D2></FONT> </DIV> <DIV><FONT size=3D2> Hope to see you all at ASA Fort = Lauderdale=20 in a few weeks!</FONT></DIV> <DIV><FONT size=3D2></FONT> </DIV> <DIV><FONT size=3D2>Best wishes,</FONT></DIV> <DIV><FONT size=3D2></FONT> </DIV> <DIV><FONT size=3D2>Bill Hartmann</FONT></DIV></BODY></HTML> ------=_NextPart_000_00D2_01C1728C.2E1069A0--