It’s HOW You Say It

Tremendous time and effort are spent on word choice – drafting the perfect motion in limine, opening statement, and/or closing argument.  However, it may be that the more time spent on how the ideas are delivered will enhance persuasion more than the words used.

This is brought home in a new research paper, How The Voice Persuades.  Van Zant, A. B., & Berger, J. (2019, June 13). How the Voice Persuades. Journal of Personality and Social Psychology. Advance online publication.

The focus here is on “paralanguage,” defined as the use of the voice – sound, pitch, volume, speed of delivery – and nonverbal communication such as gesture, pausing, and movement.

The importance of paralanguage has not escaped judicial attention.  One case explained that an appellate court must defer to a jury’s interpretation of

an audio-recorded statement as opposed to a written transcript. Spoken language contains more communicative information than the mere words because spoken language contains “paralanguage”—that is, the “vocal signs perceptible to the human ear that are not actual words.” Keith A. Gorgos, Lost in Transcription: Why the Video Record Is Actually Verbatim, 57 Buff. L. Rev. 1057, 1107 (2009). Paralanguage includes “quality of voice (shrill, smooth, shaky, gravely, whiny, giggling), variations in pitch, intonation, stress, emphasis, breathiness, volume, extent (how drawn out or clipped speech is), hesitations or silent pauses, filled pauses or speech fillers (e.g., ‘um/uhm,’ ‘hmm,’ ‘er’), the rate of speech, and extra-speech sounds such as hissing, shushing, whistling, and imitations sounds.” Gorgos, supra at 1108. The information expressed through paralanguage is rarely included in the transcript, as there is generally no written counterpart for these features of speech. Gorgos, supra at 1109.

People v. Hadden, 2015 IL App (4th) 140226, P28, 44 N.E.3d 681, 685-686, 2015 Ill. App. LEXIS 953, *10-11, 398 Ill. Dec. 652, 656-657.

How The Voice Persuades put paralanguage to the test, seeing whether how a message was delivered impacts listener receptivity, in particular whether the audience will believe the presenter’s contention.

A series of experiments was conducted where the effect of paralanguage was assessed.  Important to the researchers were two phenomena – detectability and confidence.  “Detectability” addresses whether the listener can detect a goal of being manipulated, one that is often found in word selection but less manifestly in how words are delivered.  “Confidence” is the speaker conveying “attitude certainty,” i.e., a strong subjective belief in the expressed belief(s).

In one experiment, speakers either did or did not disclose that they had been paid to review the item (a tv) they were promoting.  While disclosure of course allows detectability, the impact of paralanguage- varying the presentation in its delivery – increased receptivity of the message even when the speaker’s intent was disclosed.  As the study reports, “even when presented with information known to increase the salience of communicators’ persuasive intentions, participants did not become more likely to resist paralinguistic attempts.”  Plain English – even when listeners were told that the speaker was paid to review the item, paralanguage made more people receptive to the message that this was a good tv to purchase.  One conclusion was that speaker confidence overrode the distrust of knowing the presenter has an agenda.

And which paralanguage cues were most effective?  Again, the report details the findings:

Speakers were more persuasive when they spoke at a higher volume (z _ 2.64, p _ .008) and when they varied their volume (z _ 2.14, p _ .033). Notably, these two cues were both displayed by speakers when engaging in paralinguistic persuasion attempts. Though speakers increased their pitch, pitch variability, and speech rate during paralinguistic attempts, these cues did not impact attitudes…


[S]peakers’ paralinguistic persuasion strategy of increasing their volume and varying their volume made them appear more confident, which in turn made them more persuasive.

What is the upshot?  The authors acknowledge the need for further research, and urge that more be done to assess whether additional variables – in particular “increased pitch, increased speech rate and fewer pauses” will also impact acceptance.  And in domains where accurate judgments are paramount[,]” it will be “faster speech rate, fewer pauses and falling intonation” that may enhance listener acceptance.

For now, the lesson is simple – just as we were once taught that “the medium is the message,” it is sound as well as content that may be core to persuasion.