Subject: Pre-emptiveness From: "Albert Bregman, Tel: 514-398-6103" <IN09(at)MUSICB.MCGILL.CA> Date: Mon, 21 Sep 1992 18:13:02 EDTI want to reply to the people who have sent me comments on my proposed experiment so far. In general I want to thank you all for your comments and suggestions: Daniel Levitin and Arty Samuel: I AGREE THAT THE PROBLEM OF GETTING THE SUBJECTS TO TREAT THE SIGNAL SYNTHETICALLY IN THE NON-SPEECH BIASING CONDITION WILL BE HARD, BUT IS TRUE THAT IT IS NECESSARY TO CREATE A WHOLISTIC BIAS IN THE NON-SPEECH INSTRUCTIONS TO MATCH THE SYNTHETIC BIAS IN THE SPEECH INSTRUCTIONS. IF IT TURNS OUT THAT ONLY WITH FAMILIAR OR FAIRLY INTEGRATED SOUNDS IS THERE THE POSSIBILITY OF A SYNTHETIC BIAS, THE EXPERIMENT MAY OBSERVE SUPPRESSION OF COMPONENTS IN THE SPEECH CONDITION NOT BECAUSE THE TASK INVOLVES SPEECH, BUT BECAUSE IT INVOLVES A GLOBAL PATTERN FOR WHICH THE SUBJECT ALREADY HAS A SCHEMA AND CAN LISTEN SYNTHETICALLY. Bruno Repp and Yoshi Nakajima: It is clear that we can also hear the qualities of the sound(s) in speech or speechlike signals. Whalen & Liberman's explanation is that the speech recognizer only needs a little energy. What is left over can be used to form other perceptual qualities. This was the implica- tion of the experiment by Whalen and Liberman in Science a few years ago. The experiments that you proposed are excellent, Bruno. I hope you will get around to doing them some time. Yoshi, the possibility that we may be partitioning the synthetic speech signal into parts that contribute vs. those that are left over to supply other percepts is like the Whalen & Liberman propo- sals mentioned above. Your proposal would allow the speech recognition to subtract components. theirs allows it to subtract small amounts of energy from components, making the test of their proposal even harder. Bill Hartmann: The difficulty of biasing adult subjects may not be as difficult as you think. I agree that it would be impossible if the signals were good exemplars of the patterns in question. However, sine-wave-analog speech is not always heard as speech, so I am hoping that it would be possible to prevent it. Another precaution would be a post-experimental interview in the style of the social psychologists to determine whether the manipulation was effective. Then reclassify the subjects who were unaffected. In general: I agree that the issue is not whether the exact claims of Liberman are or are not correct, but exactly what the relationship is between speech perception and other aspects of perception. Perhaps we could draw up a list of questions. Here are a few. Can any of you think of more, or of better ways of expressing them? - Does speech perception act like other processes that extract a global pattern from data that is susceptible to being perceived at both a global and a part level? - Does it matter that the global description and local descriptions are framed in terms of different concepts (say phonetic vs. tonal)? - Does a global percept suppress or otherwise interfere with percepts based on the parts? Does the suppression also go in the other direction? Re Claim-staking: George Mandler once said to me years ago, "good experimental ideas are a dime a dozen. The important thing is to bring them to a successful experimental conclusion." I partly agree. I am not so worried about claim-staking as long as we can avoid any "chilling" effect. ("The other guy's going to do it, so I'd better not.") My feeling is that two people are unlikely to do it exactly the same way, and we will learn something about the issues from the two slightly different approaches. If the results agree, that means they are robust and not affected by small details of procedure. If not, then we face the challenge of reconciling them. Given the rareness of replication in psychology research, we shouldn't hesi- tate to tread on each other's toes. Physicists seems to be obsessed with who thought of something first or did it first (no offense, Bill Hartmann). I don't think I am going to get the Nobel Prize anyway, so I'm not worried. Any candidates for the Big One out there need not share their ideas. - Al Bregman