My apologies if you arrived here seeking an audio summary of the chapters in The Interpersonal Communication Book, 13th edition. The QR code used by the publisher was incorrect and will, I’m told, be corrected in the next printing. In the meantime, you can go to www.mycommunicationlab.com to hear the summaries. Again, I apologize for this error.
According to the American Heritage Dictionary of the English Language, the English word noise comes from the French nois which came from the Latin nausea, meaning “a feeling of sickness.” It seems that the word’s meaning generalized from a feeling of sickness (originally it referred to sea sickness particularly) to a general feeling of discomfort and then narrowed to the discomfort or disturbance brought about by excessive or unwanted sound.
In popular usage noise can refer to a wide variety of sounds, almost all of them unpleasant. You might, for example, describe annoying music, not as music but as noise. Sometimes noise is used to refer to messages that are unimportant or that can be disregarded as in “Don’t mind him; he’s just making noise.” And sometimes, it’s used to refer to a means of attracting attention as in “If you want their attention, you better make some noise.” It can also be used to allude to tentative intentions, as in “She’s making noises about finding another position.” At times, the word can even have a positive connotation as in “He was comforted by the noise from the rustle of the leaves.”
In communication, noise is generally defined as the interference that distorts the message a speaker sends to a listener. It’s a measure of the difference between the signal the speaker sends and the signal that the listener receives.
Generally when we think of noise we think of audible interference, for example, the roar of traffic, the neighbors’ blasting television, or the dog barking. We can consider these examples as noise because they can all interfere with the ability of a listener to hear what the speaker is saying. However, let’s say your dog was lost and you heard it barking. In this case, the barking would no longer be noise; it would not be the sounds that interfere with your receiving a message—it would be the very message you want to hear so you’d be able to locate your lost dog.
Because sounds can be both noise and not noise, it’s useful to distinguish between signal and noise. Signal refers to the messages you want to hear; noise refers to the messages you don’t want to hear, the messages that interfere with the messages you want to hear (i.e., the signals). For example, when you search the web for information, your search engine is likely to pull up a variety of websites that you’re not interested in along with those in which you are interested. The websites you’re not interested in may be considered noise; the websites you want may be viewed as signal.
From this distinction between signal and noise comes the signal-to-noise ratio, a measure of the amount of noise relative to the amount of signal. A web search that produces lots of desirable material (i.e., lots of signal) and little undesirable material (i.e., little noise) would be high in S/N ratio. A web search that produces more noise than signal would be low in S/N ratio. Looked at in this way, effective communication would be high in signal and low in noise; ineffective communication would be low in signal and high in noise.
Most often we think of noise as auditory; it refers to the airborne sounds that interfere with the airborne signal you want to hear. But the term—especially in communication—also refers to interference in writing. Misspellings, creases in the paper, pop-ups on your computer screen, spam, and just about any visual interference with the messages you want to receive would also be considered noise. Imperfections in digital images (red specks where there should be yellow, say) may also be considered noise.
In the Interpersonal Communication Book and Interpersonal Messages, I identify four kinds of noise. These four are probably not the only kinds of noise that could be identified and other classifications are certainly possible. But, for a broad understanding of this important concept, these four seem to work well.
1. Physical noise is the interference that occurs in the environment—the hum of a light fixture, passers-by talking on the phone, or birds chirping.
2. Physiological noise refers to barriers existing within the people communicating; for example, a hearing loss, impaired vision, or a cleft palate may all distort the auditory and/or visual signals.
3. Psychological noise refers to cognitive or mental interference such as a deep-seated prejudice that prevents the signals from being received as clearly as they might be. For example, the deeply prejudiced person might be rehearsing counter arguments and not fully hear or read the messages being sent.
4. Semantic noise occurs when the communicators don’t share the same meaning for the words used. Overly complex terms or dialectical variations in meaning can easily produce semantic noise.
One important additional point needs to be made here and that is that noise can never be eliminated entirely. There will always be some degree of noise in any and all forms of communication. You can’t eliminate it. But you can strive to reduce it. You can reduce physical noise by structuring the environment, closing the windows to block out noisy traffic or shutting off the television to reduce the competing messages. You can compensate for physiological noise by repeating your message, speaking at a higher volume, or avoiding covering your mouth when you talk so your lips can be read. You can reduce psychological noise by becoming aware of and combating your own biases and prejudices. And you can reduce semantic noise by asking questions when meanings are not clear or defining terms that you think your listener won’t understand. As you’ll see these suggestions are covered throughout your texts.
You can also view advances in communication technology as ways to lessen noise. Today’s search engines, for example, are much more efficient than were those popular 10 or 15 years ago; that is, they contain more signal and less noise. Fiber optic cables, to take another example, contain less noise than metal cables and therefore make communication easier and more pleasant. Technological advances in digital imaging enable artists to remove noise from graphic images. On the other hand, other technological advances have enabled advertisers to add noise to our systems in terms of pop-ups, spam, and animated advertisements on many web pages. In the same way, television shows regularly run ribbons at the bottom of the screen to provide a variety of messages and frequently use pop-ups to announce new shows. If you're interested in the current show, these pop-ups are noise; if you're interested in what's on next, then the pop-ups are signal.