August 12, 2015

August 12, 2015

Written by Maximus Peperkamp, M.S. Verbal Engineer

Dear Reader, 

This writing is my twelfth response to “Talker-specific learning in speech perception” by Nygaard and Pisoni (1998). These researchers focus on something which has been apparent to me for a long time. It has often bothered me that what seems obvious to me is not accepted, let alone understood, by others. With certain people and under certain circumstances I am able to talk, think, feel and function coherently, but with other people and other circumstances I stumble over my words, I cannot think, I cannot remember and I only seem to make mistakes. 

I recognize myself in what these authors write about. “In our use of language, we are often aware that through exposure to and learning of a novel talker’s voice, for example, we become increasingly able to recover the linguistic aspects of an utterance that seemed difficult to understand only moments earlier.” This positive occurrence is one which I would call Sound Verbal Behavior (SVB), in which the speaker’s voice has a positive effect on the listener. The influence of this “novel talker’s voice” is in stark contrast to the Noxious Verbal Behavior (NVB) speaker’s voice, which has a negative effect on the listener. The more “exposure to and learning of” a SVB voice can occur, the more capable and confident we seem to become.

“Perceptual learning involves an increase in the ability to extract information from the environment, as a result of experience and practice with stimulation coming from it. Gibson (1969) has identified two types of perceptual learning.” One type suggests “that perceptual sensitivity can be enhanced by pre-exposure to a set of stimuli.” In this type “Mere experience of the stimulus domain increases perceivers’ sensitivity.” If we consider the sound of the speaker’s voice as “stimulus domain”, we find that exposure to both SVB as well as NVB increases the listener’s “perceptual sensitivity.” However, if the listener is more exposed to NVB than to SVB, a different kind of sensitivity begins to occur in the listener, who will become biased to whatever he or she has been most often exposed to. 

“In the second type, explicit experience in categorizing or identifying stimuli allows perceivers to become attuned to specific diagnostic physical features.” Thus, the listener’s “experience in categorizing or identifying stimuli” as belonging to the SVB or NVB category depends on the ways in which he or she was conditioned.  Authors describe this learning process “which allows the perceivers to become attuned to specific diagnostic physical features.” However, such becoming “attuned” of course only applies to SVB, because NVB is only about coercion and obedience.

“For this type of learning, the organization of stimuli into categories has been shown to have an important influence on subsequent perceptual sensitivity.” The listener’s “perceptual sensitivity” is  shaped by the extent to which he or she is more often exposed to SVB or NVB. I was never able to learn much from speakers who had a lot of NVB and little or no SVB. From an early age I favored SVB speakers, because with them was I able to learn and do something right. With NVB speakers, such as my father, I couldn’t do anything right. 

“In the case of talker learning, categorizing or identifying talker’s voices may lead to increased distinctiveness of the perceptual dimensions of talker identity.” Although I was affected by the rejection of my father, luckily there were plenty of SVB speakers in my family, such as my mother, my grandmothers and my uncle, who supported and encouraged me. However, since they did not have any education, they couldn’t play a significant role in my academic development. Their primarily emotional support allowed me to listen to myself and figure out that I needed SVB to succeed in life. 

“If a benefit of perceptual learning of voice can be demonstrated for linguistic processing as well, it would suggest that the same underlying dimensions subserve both perceptual abilities.” Such a “benefit of perceptual learning” can be demonstrated with SVB. Everything I have achieved is in my opinion due to SVB. In the studies reviewed by these authors “it has been found that a number of factors, such as the a priori distinctiveness of the set of voices to be learned, the number of talkers to be identified or discriminated, and the length or duration of the utterances used during training (i.e., syllables, words, phrases, passages), can mediate learning of voices.” Another way of summarizing these results is to state that in SVB we really listen to each other, because we acknowledge that it takes time to have a conversation. In NVB, on the other hand, we are always in a rush and stressed, as, supposedly, there is not enough time. 

“Not surprisingly, listeners learn to recognize talkers’ voices most readily when utterances of long duration from a few highly distinct talkers are used.” In NVB, the speakers dominate and intimidate the listeners and talkers struggle to get the attention from other talkers, by forcing them to remain listeners. Moreover, in NVB communicators don’t give each other the time to speak and cut each other off whenever they can. “These results suggest that a period of perceptual learning is required for listeners to become sensitive to talker-specific information in the speech signal.” Only SVB has such “a period of perceptual learning” for the listener. In NVB no such learning period is needed as the speaker coerces the listener.

The author’s conclusion that “Listeners do not appear to acquire expertise in talker recognition effortlessly, but rather learn over time to attend explicitly to the unique, acoustically distinct properties of each talker’s voice” is clearly based on the ubiquity of NVB. Talking and listening is perceived as effortful only during NVB, but during SVB these two behaviors occur effortlessly. The fact that learning occurs “over time” does not have to mean that learning involves any effort. However, given the common lack of time which is experienced when we have NVB, the authors equate the lack of time with effort. In SVB we take more time to talk, but it takes no effort.