The Biologically-Based Bias of Personality Disorder Diagnosis.

More than previous versions, the American Psychiatric Association's (2013) fifth edition of the Diagnostic and Statistical Manual of Mental Disorders (DSM-V) formally specified the nature of a personality disorder. Going beyond specific personality disorders and their respective criteria sets, are the General Criteria for Personality Disorder (GCPD) provided in section III on page 761 of DSM-V. Much of this list simply specifies that impairments must be enduring-transcending time, place, medical status, and developmental period. It is only the first two, criterion A and criterion B, which positively define a personality disorder. Specifically, criterion A states that there must be “moderate or greater impairment in personality functioning,” and criterion B states that there must be “one or more pathological personality traits.” Thereafter, on page 762, the DSM attempts to define and operationalize the concepts of pathological personality traits and impaired personality functioning. First, DSM-V operationalizes pathological personality traits in so far as five are listed: (1) negative affectivity, (2) detachment, (3) antagonism, (4) disinhibition, and (5) psychoticism. Second, in describing personality functioning, there is mention of disturbances in self and interpersonal functioning, which are taken to “constitute the core of personality psychopathology.” DSM-V proceeds to parse self and interpersonal functioning further: “Self-functioning involves identity and self-direction; interpersonal functioning involves empathy and intimacy.” All such efforts are commendable improvements on what would otherwise have been imprecise concepts liable to hold different meanings for different readers. Precision is gained by exposition. Yet, precision invites criticism. With implicit assumptions giving way to explicit assertions, as collected across various tables, terms, and operational definitions within the GCPD, personality disorder diagnosis can be recognized as relativistic. When clinical judgment, diagnostic tradition and psychiatric authority are exchanged for empirical research, one finds personality variables like those embodied in the GCPD unassociated with deficits in vocation, mating success, finance, and health (Ullrich et al., 2007; Gutierrez et al., 2013; Vall et al., 2015). At any point along the continuum of personality, instead of unalloyed deficits and beneficial traits, humans experience fitness relevant trade-offs (Nettle, 2006; Brumbach et al., 2009), as do damselflies (Rodin and Johansson, 2004), rainbow trout (Schjolden et al., 2006), house mice (Rauw, 2006) and a host of other animals displaying rudimentary personalities (Bell, 2007; Wolf et al., 2007; Biro and Stamps, 2008; Dammhahn, 2012; Favreau et al., 2014). What is true for traits may be true for personalities. As previously reviewed (Hertler, 2015a), psychopathy and obsessive compulsive personality disorder have both been described as strategic, evolved patterns, rather than dysfunctional personality disorders. Moreover, a recent study found personality extremes consistent with DSM-V disorders to be sexually selected via female choice (Vall et al., 2015). With the fact of relativism being elsewhere treated (Hertler, 2015b), it suffices to state that the GCPD rests on clinical assumptions of pathology which do not appear to equate to impairments in evolutionarily relevant life outcomes. Herein, it is not the question of relativism itself that is pursued, but the nature of that relativism. GCPD criteria are neither arbitrarily relativistic nor culturally relativistic; instead they show a particular bias, comprehensible only from a life history evolutionary vantage point. Bringing a life history evolutionary perspective to bear Life history evolution is a coherent sub-discipline of evolutionary biology that originated with the study of variation across seven developmental trait clusters, among which were lifespan, maturation rate, and brood size. Life histories are distributed across a gradient from fast or r-selected, to slow or K-selected. Most basically, and confined to the classic biomarkers upon which life history theory was grounded, fast and slow relate to the pace of development. Fast or r-selected species mature quickly, breed much, and die young, whereas slow or K-selected species show the opposite pattern, living long enough to support extensive prenatal growth and thereafter lavish resources on a small number of long-lived young. Contrast the elephant with the rabbit. In number, size, and care of young, as in longevity, growth and maturation rate, these animals are extraordinarily dissimilar. Life history variation, though greatest between species, is present within species; including the human species. Within the past three decades, life history evolution has been particularly successful in logically grouping altruism and affiliation, risk aversion and inhibition, as well as future oriented thought and delay of gratification (Figueredo et al., 2006; Jonason and Tost, 2010; McDonald et al., 2012; Hertler, 2015a), showing them to be K-selected. Opposite these, across a continuum, are r-selected antagonism, sensation seeking, disinhibition, and an orientation to the present. The original biological, as well as the aforementioned psychological and social life history variables, are collectively calibrated by mortality; specifically the rate, predictability and controllability of mortality. In K-selected regimes, mortality is rare, predictable and controllable; in r-selected regimes, mortality is common, unpredictable, and uncontrollable (Schechter and Francis, 2010). As investing in a few, slow growing, late maturing young is impractical and maladaptive under an r-selected regime with high, and highly unpredictable mortality, so is excessive altruism, risk-aversion or future orientation. There is not sufficient time or safety to capitalize on investment. So, life history creates a sort of time relevant biology organized around mortality.