In my training as a speech-language pathologist, I learned about something called categorical perception. The best way to describe it is to consider two speech sounds that are close to one another, for example “ee” as in “heat” and “ay” as in “hate”. The position of the tongue for these two sounds is very close; only a small shift or glide is needed to move from “ee” to “ay”. The practical implication for this when we speak is that the tongue never truly lands in exactly the same place reliably. Therefore we are almost always actually hearing something that exists somewhere between a pure “ee” and a pure “ay”. Yet we never perceive this. Our perceptual system automatically assigns what we hear to either the “ee” or “ay” category depending on the context and where on the continuum between “ee” and “ay” the tongue happens to land.
In terms of meaning, it is practical to be able to tell the difference between these sounds. Categorical perception allows us to understand whether someone is saying “Low income residents will be given heat subsidies” versus “Low income residents will be given hate subsidies. Our ability to navigate slight differences in articulation of speech sounds helps us to understand speech even when the speaker has an accent that is different from your own.
In our neurology class, we learned about the concept of “referred sensation”, which is where we feel discomfort in a part of our body that is distant from the site of the actual disorder, irritation or injury. Because of this default of perception, the professors and clinical supervisors reminded us frequently not to take patients’ descriptions of the location of their discomfort at face value, but instead to conduct a full examination.
After engaging in clinical practice for some time, I began to understand the myriad ways in which perception leads people astray. We never hear our own voices the same way in which others do. When helping people through vocal rehabilitation, sometimes their voices return to old non-functional patterns because their perceptual systems are telling them that the new vocal pattern is not “normal” and therefore sounds “strange”.
The evidence for the lies that perception tells is all around us. Consider the research regarding crime witnesses. It appears that more often than not two people witnessing the same crime will disagree on the details and at times the major elements of what they saw.
Given these conditions, why is it that we trust our perceptions when it comes to our physical environment, our bodies and our identities? Why do we trust that when our eyes tell us we see a solid object that it is in fact so? Why do we invest so much in our perceptual interpretation of our preferences and what is “good” and “bad”. In this circumstance it makes an enormous amount of sense instead to make a practice of questioning our perceptions whenever we recognize we are becoming convinced that they are incontrovertibly true.
Do you have any episodes of faulty perception that helped you recognize a moment of prajna? Comment and share!
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