How we evaluate and experience our environments and our rather consistent emotional behavioral patterns remains linked to ancestral affective “memories” (intrinsic circuit functions), shared by all mammals, as they guide the maturation (and specializations) of our higher (neocortical) mental apparatus. In short, the causal, developmental infrastructure for personality development has to be bottom-up, before the top can provide regulatory guidance to the whole.
Furthermore, a top-down approach is largely correlational and cannot easily test for causal underpinnings with the kinds of neurochemical, neurophysiological, and detailed neuroanatomical research that can be conducted with animals. The top-down approach does not start with underlying evolutionary processes and mechanisms that can be evaluated neuroscientifically. At its best, it accepts top-down, statistically derived models and attempts to correlate them with possible underlying biological mechanisms (DeYoung, 2014). (For a critique of the mapping of top-down approaches onto brain structures, see Poldrack, 2010).
However, many top-down theorists seem content with correlational research when trying to reveal underlying biological mechanisms. We write content with tongue in cheek, of course, for we realize that the power of neuroscience is a much more recent scientific development than semantic-psychological and mathematical-statistical approaches. In fact, the kind of brain research that can be conducted on animals is simply not possible for psychologists studying humans. In any event, we are not suggesting that what has preceded us has not had value; it clearly has in laying out the broad psychological topography of personality dimensions. Our goal is to reaffirm how cross-species neuroscience and genetics have finally opened up the Pandora’s box of BrainMind complexities that the great pioneers of the field simply could not consider adequately.
In sum, our perspective is that the clarification of the biological mechanisms underlying our personalities requires first achieving an evolutionary bottom-up understanding of human emotions and other affects, which requires the kind of manipulative brain research that is readily (and ethically) performed in animal models but difficult to conduct on humans. Of course, the ethics of neurobehavioral research on animals is problematic (especially for the most highly aversive negative feelings, engendered by FEAR and PAIN), but it is being done, and probably will continue to be done (hopefully, in ever better ways, as reflected in the current “gold rush” to implement optogenetic and DREADD technologies—the first being discrete stimulation of specific brain neurochemical systems with light—and the latter being designer receptors exclusively activated by designer drugs).
As our relevant knowledge base expands, many novel linkages to understanding human brains/minds will emerge. It will be on such foundations that a fuller understanding of both animal and human personalities will emerge, as well as a more satisfactory understanding of human psychopathologies and their treatment (Panksepp, 2005, 2015, 2016). Indeed, our move away from behavior-only preclinical (i.e., animal research) models of psychiatric disorders to ones that focus on the brain substrates of primary-process core affects (Panksepp, 1998a) has already yielded some promising therapeutic breakthroughs (Panksepp et al., 2014; Panksepp & Yovell, 2014), which are further discussed in Chapter 18. With these conceptual preliminaries out of the way, we now further consider how studies of human tertiary personality assessments have parsed human personality structures, without considering the relevant brain issues.
THE TOP-DOWN BIG FIVE OUTSIDE THE LEXICAL WORLD
We conclude this chapter with a foray into the Big Five world, by way of a brief review of Colin DeYoung’s ideas. DeYoung is a rising young personality psychologist at the University of Minnesota with new insights that illuminate the difficulties we have just meandered through. Colin offers a new top-down approach to personality research among a large community of researchers that still focus on traditional questionnaire measures of the five-factor model such as the revised NEO-PI (McCrae & Costa, 2010). Although not yet integrated with the kind of neuroscience approach advocated here, DeYoung offers something new within the history of personality theory. We offer the following as commentary rather than criticism.
First, what might we expect from a personality psychologist still aspiring to take a top-down approach? We would certainly expect him to take a more cognitive than affective approach to personality. Accordingly, DeYoung uses the Big Five as a starting point but sees behavior more in learning-theory terms and conceives of personality theory as the study of goal-directed, self-regulating systems. He has proposed the Cybernetic Big Five Theory (DeYoung, 2014), which incorporates a stimulus–response–feedback model into personality that is more consistent with a traditional cognitive-learning concept of personality than with the affective evolutionary approach espoused in this book. But this is also closer to our view, for we see affects (especially their environmentally induced shifts) as being absolutely critical ingredients in the instantiation of learning and memory.
What else might we predict? We would expect him to take a statistical approach to identifying personality dimensions. Correspondingly, DeYoung has theorized that the Big Five is organized on four hierarchical levels (DeYoung, Quilty, & Peterson, 2007; DeYoung, 2010). He used factor analysis to identify two metatraits that he labeled Stability and Plasticity, which together comprise the first level. This was consistent with others who had previously argued that the Big Five could be summarized with two similar higher-order factors labeled Alpha and Beta: Alpha representing the socialization processes by which “the child develops superego and learns to restrain or redirect id impulses and to discharge aggression in socially approved ways” and Beta representing “personal growth versus personal constriction” (Digman, 1997, p. 1250). Alpha “involves the common aspects of Agreeableness (vs. Hostility), Conscientiousness (vs. Heedlessness), and Emotional Stability (vs. Neuroticism),” with Beta fostered by traits such as “outgoing, adventurous, expressive, and active (Extraversion), and creative, imaginative, and open to new ideas and change (Intellect)” (pp. 1249–1250).
Going in the narrower direction, Costa & McCrae (1995) had offered six subscales, or facets, for each of their five factors. However, based on a previous twin study of five-factor facets reported by Jang et al. (2002), which found statistical evidence that two genetic factors were necessary to explain the variations in the facet scores of each of the five factors, DeYoung argued that a third layer of aspects needed to be inserted between the Big Five factors and their more numerous facets.
DeYoung again used factor analysis to empirically derive his third layer of ten aspects. Under Neuroticism (low Emotional Stability) he found Withdrawal and Volatility; beneath Agreeableness were Compassion and Politeness; below Conscientiousness were Industriousness and Orderliness.4 At the next lower level for Extraversion were Enthusiasm and Assertiveness; and Openness/Intellect simply divided into the aspects of Openness and Intellect.
At the fourth level, the bottom level just below the aspects, DeYoung placed the facets, which were only rationally derived with no consensus regarding their number. For both the metatraits above the Big Five dimensions and the aspects inserted at a third level just below them, DeYoung relied on statistics to identify important dimensions rather than using affective neuroscience tools to grapple with what survival systems might be inherently embedded in the mammalian brain. But we think these ideas can be brought together.
Lastly, we would expect a top-down personality psychologist to overly rely on human cortical functions when searching for brain mechanisms underlying personality dimensions. Using neuroimaging (DeYoung et al., 2010), about 75 percent of the brain sites reported were neocortical, with fewer evolutionarily older cortical areas such as the cingulate cortex and the hippocampus, as well as two basal ganglia structures, the amygdala and the nucleus accumbens. One reason may have been that those top-brain regions are simply much larger and contain many more neurons that fire at stupendous rates (to handle the dynamic flow of real-life cognitions). Subcortical areas are tiny by co
mparison; their neurons fire at much lower overall rates and consequently are much harder to measure in brain imaging research.
We applaud DeYoung’s focus on actual neurobiological mechanisms to help explain his identified personality aspects, but he remains in the more cognitive, top-down camp, although with the potential to integrate seamlessly with our bottom-up foundational approach. Indeed, we suspect that it is on the seamless integration of top-down and bottom-up approaches that the fecundity of future personality theories will depend.
Although DeYoung seems committed to the top-down approach to personality, we suspect he would have little problem integrating what we focus on here. Still, he has written “that personality neuroscience needs personality psychology more than the other way around. The accomplishments of the last 75 years in personality psychology should be guiding neuroscientists as they explore individual differences. We have mapped out the phenotype with remarkable success. . . . If personality neuroscience fails to avail itself of this knowledge, its results will accumulate piecemeal and will not inform us coherently about the individual as a whole” (DeYoung, 2007). So, for now, we simply note synergistic findings from our bottom-up approaches (Montag, Reuter, Jurkiewicz, Markett, & Panksepp, 2013).
Yet, having mapped out emotional phenotypes, we note that in our view two of the Big Five dimensions, Agreeableness and Emotional Stability, are compounds that comprise more than one primary emotional brain system. As reviewed in Chapter 2, we found the positive pole of Agreeableness to be associated with the subcortical CARE system, and the negative pole with the RAGE/Anger system. Similarly, the negative pole of Emotional Stability combined with all three negative primary emotions, RAGE/Anger, FEAR/Anxiety, and PANIC/Sadness. Importantly, overactivity in each of the negative primaries is associated with distinct major psychopathologies (psychopathy, anxiety disorders, depression, and panic attacks), with unique developmental trajectories and different therapeutic treatments.
What is to be gained by not incorporating solid affective neuroscience evidence into personality theory and giving these three brain systems, which contribute so heavily to dysfunctional lives suffering from the likes of antisocial behavior, disabling anxiety, panic attacks, and suicidal depression, the focus they deserve? Would it not be useful to consider and treat imbalances of these emotions as primary personality dimensions rather than lumping them into a single Emotional Stability/Neuroticism dimension? Similarly, why not recognize that there appears to be no higher-order Agreeableness system in the subcortical brain, and thereby increase focus on the clinical issues presented by pathologically low CARE (leading to low empathy by one path) and hypersensitive RAGE/Anger systems (leading to low empathy by another path)?
From our bottom-up perspective, the danger may be that it is the top-down research that “will accumulate piecemeal” data that may not adequately represent and prioritize our evolved human affective nature as a whole. Still, it is puzzling why so many top-down researchers do not recognize the value of our evolved, cross-species, psychobiological roots, capable of only being studied well in comparative cross-species studies, already offered by affective neuroscience. The cortex may be essential for the development of our unique human cognitive capabilities, but it is not necessary for the expression of basic mammalian affective personality characteristics. The danger of neglecting “real” affective brain-mind foundational issues for personality theory may be that, without a rich understanding of the subcortical BrainMind (which only brain research on other animals can provide), we may run the risk of failing to understand either human self-actualization or diverse pathological dysfunctions, from psychiatrically relevant personality disorders to many everyday personality problems, such as obsessive gambling and other diverse impulse control problems (e.g., addictive disorders emerging from the general-purpose SEEKING system). All of these arise from evolutionarily deeply ingrained affective systems of mammalian brains.
Humans are indeed a deeply affective species, quite similar in this respect to the other mammals. This primary level (“natural kinds”) needs to be represented more explicitly in personality theorizing. Perhaps higher cortical mechanisms and cultural proclivities can elaborate our primary tools for living into other seminatural “tertiary kinds,” but they should be seen as derivatives of our fundamental genetically based, psychoneurological nature. An understanding of emotional affects may be a key to bringing bottom-up cross-species affect studies and top-down human personality approaches together in a mutually beneficial synthesis.
CHAPTER 7
Our Ancestral Roots
Personality Research on Great Apes
There can be no doubt that the difference between the mind of the lowest man and that of the highest animal is immense. An anthropomorphous ape, if he could take a dispassionate view of his own case, would admit that, though he could form an artful plan to plunder a garden—though he could use stones for fighting or for breaking open nuts—yet that the thought of fashioning a stone into a tool was quite beyond his scope. Still less, as he would admit, could he follow out a train of metaphysical reasoning, or solve a mathematical problem, or reflect on God, or admire a grand natural scene. Some apes, however, would probably declare that they could and did admire the beauty of the colored skin and fur of their partners in marriage. They would admit that though they could make other apes understand by cries some of their perceptions and simpler wants, the notion of expressing definite ideas by definite sounds had never crossed their minds.
Nevertheless the difference in mind between man and the higher animals, great as it is, certainly is one of degree and not of kind.
—Charles Darwin, The Descent of Man
TO HELP HIGHLIGHT the continuity of personality construct across species, we devote this chapter and the next two to three species: the one that is evolutionarily closest to us (chimpanzees), the one with whom we have historically had the closest relations (dogs), and one that has brought us much misery historically (plagues) yet also has served us so well in medicine and neuroscience (rats). We also briefly touch on those vertebrates that are about as distant from us as any other living vertebrate species (fish). Our hope is that this progression will help readers appreciate the gradients of personality that reach far back in evolutionary time, even as the neuropsychological (albeit not the behavioral) details get harder and harder to fathom as the evolutionary distance between ourselves and other species increases. We provide some detailed coverage for students of personality, although general readers may wish to pass over some materials.
OUR CLOSEST LIVING EVOLUTIONARY RELATIVE
Chimpanzees are the closest living phylogenetic relatives of human beings. Humans share approximately 98.8 percent of our DNA with chimpanzees (Chimpanzee Sequencing and Analysis Consortium, 2005), and a recent analysis suggests humans and chimpanzees may share a common ancestor as recently as 4 million years ago (Hobolth, Christiensen, Mailund, & Schierup, 2007). Therefore, to the extent that personality is influenced by brain biology, one would expect chimpanzees to exhibit the most similar personalities to humans among the vast varieties of nonhumans with which we share this planet.
Indeed, many have explored how similar chimpanzees and humans actually are. Frans de Waal has written that chimpanzees form political alliances to help them maintain power and status within their social group (de Waal, 1982) and exhibit dispositions for moral behavior (de Waal, 1996). Chimpanzee cultural differences between social groups have also been described, including the use of medicinal plants (McGrew, 1992, 2004). Jane Goodall documented chimpanzees making tools and hunting small mammals (Goodall, 1986). While Goodall, in a manner of speaking, moved right into the homes of wild chimpanzees in Africa, others have adopted chimpanzees into their homes and raised them like their own children. The most famous of these human chimp parents were Allen and Beatrix Gardner (a student of Nobel Prize–winning ethologist Niko Tinbergen), who adopted Washoe into their home and taught her to communicate with them in American Sign Language. The
pioneering chimpanzee researcher Robert Yerkes (1925) believed that chimps understood many of his words and had speculated that chimpanzees might learn to sign, but apparently no one ever tried to formally verify that until the Gardners. Since that pioneering work, many have now taught chimpanzees (and gorillas) to communicate using sign language or sign language equivalents.
CHIMPANZEE PERSONALITY AND BIG FIVE CONSCIENTIOUSNESS
Up to this point in the book, we have only discussed the Big Five Conscientiousness dimension with respect to humans. In fact, in studies using ratings of mammals using personality inventories, a Conscientiousness dimension had been lacking (Gosling & John, 1999)—until James King and Aurelio Jose Figueredo of the University of Arizona set out to answer the question, “How closely do chimpanzee personality factors resemble those in humans?” (King & Figueredo, 1997, p. 257), by attempting to verify that all of the Big Five personality factors could also be measured in chimpanzees.
Mostly drawing from Goldberg’s (1990) Big Five personality taxonomy, King and Figueredo selected forty-three descriptive adjectives and used fifty-three experienced observers to rate one hundred chimpanzees from twelve zoological parks, obtaining an average of over four observer ratings per chimpanzee. A factor analysis of these mean observer ratings yielded six factors, with Dominance emerging as the first and largest factor, which was later determined to be highly heritable in chimpanzees (Weiss, King, & Figueredo, 2000). Factors 2–6 corresponded to the human Big Five: Surgency/Extraversion, Dependability/Conscientiousness, Agreeableness, Emotionality/Neuroticism, and Openness to Experience, although the Emotionality and Openness factors were small, containing only three and two items, respectively. Confirming the validity of their findings, each of these factors except Openness was later shown to be related to behaviors that were independently observed in zoo settings (Pederson, King, & Landau, 2005). Indeed, for the first time a research team had objectively documented Conscientiousness, as well as the full Big Five personality model, in a nonhuman species, with the wrinkle that Social Dominance was added to the mix, and they had done so by obtaining ratings of adjective trait terms originally used to describe human personalities.
The Emotional Foundations of Personality Page 13