Subject: Re: maximum 'tatum' speed perception From: Erick Gallun <gallun(at)SOCRATES.BERKELEY.EDU> Date: Mon, 8 Apr 2002 14:03:26 -0700At 12:39 PM 4/8/02, Jeff Bilmes wrote: >Actually, I would surmise that 8-10Hz is a fairly large underestimate >of the maximum rate at which tatum perception can occur. Certainly Art >Tatum, for whom the term tatum was named, had a tatum rate that far >exceeded 10Hz (it was probably around 13-16Hz, or possibly higher). This made me think of the distinction raised in the Pastore, Harris and Kaplan (1982) paper "Temporal order identification: some parameter dependencies" in JASA, 71(2), pp. 430-436. In their experiments, subjects were asked to make judgements about tone-pairs with onset asynchronies. Either the high tone or the low tone came on first. In a two-alternative forced-choice task, onset asynchrony thresholds with brief (10 ms overlap) signals, were measured at roughly 5 ms. When the same subjects were then asked to "label" the same stimuli as high-low or low-high, threshold performance was only achieved at 9-10 ms. As the overlap duration was increased (and consequently the duration of the entire stimulus) up to 300 ms of overlap, a doubling of thresholds was reported. This suggests that while 8-10 Hz (roughly 10 ms) is a reasonable estimate for an identification task with standard listeners, the human ear could in fact perform the task at rates of up to 20 Hz. Erick Gallun Hafter Auditory Lab UC Berkeley