July 28, 2015

July 28, 2015

Written by Maximus Peperkamp, M.S. Verbal Engineer

Dear Reader, 

The following writing is my seventh response to the paper “Two Organizing Principles of Vocal Production: Implications for Nonhuman and Human Primates” by Owren, Amoss & Rendall (2010).

Among primates as well as among humans “factors such as the presence, relative rank, or likely response of nearby animals, are so basic as to have shaped vocal behavior in that species from its very beginnings.” Such differences are of notable “affective importance,” in other words, “arguing for specifically cognitive control of vocal output in those situations requires ruling out affective confounds, which has not been done.” 

Also humans we have not yet taken into account the affective confounds, which cause Noxious Verbal Behavior (NVB) and undermine relationships. Moreover, the argument “for specifically cognitive control” always involves verbal fixation, which prevents our voice from resonating. Hierarchical differences among humans set the stage for NVB. We have to be on guard towards everyone who sounds aversive. Such vigilance makes us outward oriented and prevents us from paying attention to negative private speech.

Threats from more powerful human beings, whom we can’t escape or avoid, always result in our internal struggle. Since this outer struggle is bound to fail and often even impossible, NVB public speech burdens us with negative self-talk, that is, with NVB private speech. Thus, 1) fixation on words, 2) outward orientation, and 3) conflict (between overt and covert speech, but also between one person and another) changes the sound of our voice. 

When we are stressed, frustrated, lost, sad, confused, overwhelmed, impatient, coerced, we sound that way. Just as monkeys “produce fewer vocalization than expected” in certain situations in the presence of particular individuals, so too do humans “volitionally suppress spontaneously affect triggered facial and vocal expressions through a process of “top-down” inhibition.” The possibility of “affective and behavioral resonance” is only available during SVB. There is evidence that “otherwise differentiated systems of producing and responding to a given behavior can exert reciprocal effects on underlying neurophysiological organization.” 

If animals can exert such effects, humans should be able to do the same. The landmark finding in this area was the discovery of primate ‘‘mirror-neuron’’ systems that are activated both by seeing an object or an action performed, and by acting on that object or performing the same action.” Such mirror-neuron systems exist in humans as well and we can only become aware of their workings when our voice sounds empathic.   

The authors conclude that “humans exhibit both a primate-like affect-triggered limbic pathway and an additional, cortically controlled, volitional vocal system. This phenomenon of parallel neural pathways in vocal production occurs across a variety of species and may represent a general outcome in evolution.” Recognition of these vocalizations in humans must involve acknowledgement of NVB and SVB. These are names given to these two cross-species occurring classes of vocal verbal behavior. 

The authors focus on primates, but I want to emphasize human vocalization, specifically that we affectively influence each other with the sound of our voice.  Like primates, we also adjust our voice to noise in our environment. This is the Lombart Effect. Indeed, we can have SVB in a noisy, aversive environments. It is our voice with which we create our environmental niche. This is particularly evident in the speaker-as-own-listener. The speaker is the only one who has excess to what happens within his or her own skin. 

“Studies with both squirrel monkeys and decerebrate domestic cats have indeed shown that the Lombard effect is mediated at the brainstem level, meaning its occurrence is likely uninformative with respect to the operation of higher level vocal control systems.” That the Lombart Effect is mediated at the brainstem level shows that in SVB no immobilization response is activated, because there is no immanent threat. 

In SVB the opposite of freezing or death feigning occurs. Although there may be a noisy and threatening environment, no activation of the immobilization response occurs, no fight or flight response is triggered. Instead the mobilization response is down-regulated. Thus, even in an aversive environment, SVB can occur.   

The authors conclusion that “although top–down cortical effects are likely important in some instances, even if these do not alter the conclusion that production is fundamentally affective in nature” is important to humans. 

“Although top–down cortical effects are likely important in some instances, even these do not alter the conclusion that production is fundamentally affective in nature. Finally, much of the evidence of convergence or divergence of calling across individuals or groups can also be explained without invoking volitional effects or cortical control.” More than we are due to our NVB capable of admitting, we are determined in our talking by affective experiences. Moreover, negative affective experiences impair our social engagement, while positive affective experiences are necessary to make social engagement possible. This is why SVB has to be established.

The authors end their paper with a salute to Darwin, to emphasize that “the single strongest commonality between primate and human vocal production lies in the central role that affect and the limbic system can have in both.” Their data “are indisputably indicative of evolutionary continuity not only among great apes and humans, but also among all primates and perhaps all mammals.” However, “vocal flexibility and volitional control” which is “so often sought in primates is largely absent while strikingly clear in humans.”

There is evidence for evolutionary continuity, the “reception-first system”, second pathway in addition to the “production-first system.”And, there are “neural phenomena in birds” similar to human vocal control, which indicate that “the beginnings of that new pathway may have already been present in a common ancestor from long ago.” Darwin was as right 140 years ago. 

His views about the “central role of affect in animal communication” are supported by these researchers. Humans evolved with neural structures, which in many ways are similar to primates and which explain why we talk the way we do. The only reason we haven’t progressed much further than Darwin’s claim, is because we are without knowing it dominated by NVB. 

If researchers themselves would have had SVB, progress would have been  made much faster. It  is in the name of our scientific endeavors that SVB needs to be addressed, taught and maintained. And if we are to survive as a culture, as a species, we need to have authentic human interaction.