Review of: Psychobiology of Personality. (2005 Marvin Zuckerman,Arnold R. Bruhn )
New York: Cambridge University Press ISBN: 0-521-81569-X, 322 pp. (hardcover);, (paperback). $100.00, hardcover; $53.00, paperback
This text provides a multifaceted look at personality from a biological perspective. The book is solidly conceived and anchored in research. It leaves philosophical ruminations to philosophers. Years ago—many years ago, it now seems—we debated as graduate students the age-old nature versus nurture question. Does nature (biology) determine what we become, or are behaviors conditioned or reinforced by powerful environmental influences? This controversy, oversimplified somewhat in my rendering of it, provoked such heated discussions as whether criminals are “bad seeds” or individuals produced by an aberrant environment—poorly parented and raised in dysfunctional, toxic environments. To illustrate the powerful role of reinforcement, for example, B. F. Skinner (cited in Schultz, 1981) demonstrated that he could train pigeons through reinforcement to play ping pong, an activity that most pigeons normally do not gravitate toward on their own. Some of the pigeons, if Skinner’s film clips are any indication, appeared surprisingly proficient at the sport.
In a less dramatic fashion, Gerry Patterson (1977) demonstrated that he could train parents to reinforce desirable behaviors in their children and extinguish undesirable ones. Social liberals who believed in a world in which all of us begin with, more or less, a blank slate as social equals pointed to studies such as Patterson’s in asserting that it is primarily a benign and nurturing environment that separates people who stand out in positive ways from their peers whose behaviors are socially aberrant.
Although the work of social liberals clearly demonstrated that animals and children can be trained and their behaviors shaped by their environment, the field began to shift more in the direction Zuckerman has taken in the psychobiology of personality. Put another way, babies are obviously not blank slates; this is clear to anyone who has been around a broad cross-section of them. Some seem from an early age almost hard wired to be more active, more anxious, more adventurous, or more fearful, despite whatever interventions parents and teachers subsequently make to reshape their behavior.
In the 1960s, Thomas and Chess (1968) undertook landmark longitudinal studies to describe categories of behavior and physiologic reactivity, such as activity level, adaptability to new environments, and response to changing activities. They found consistent and stable patterns in these variables, which they described as behavioral styles or temperaments that were evident from infancy. The authors proposed, in all, nine categories of behavior and physiologic responses. How children responded even as infants in turn impacted the parents and caused them to modify their behaviors.
Plainly put, it appears that Thomas and Chess (1968) were observing patterns that could be discerned from the beginning—not simply reinforced or conditioned by the children’s parents. For those on the nurture side of the debate, the findings of Thomas and Chess—psychoanalysts by training—were stunning. The psychoanalytic notion of good mother–bad mother began to crumble around the margins. This happened none too soon, in my judgment, as mothers had either been praised too highly or vilified by psychologists prior to the 1960s, depending on how their children turned out.
Thomas and Chess’s ground-breaking work also made it possible for researchers to look at state–trait studies with a different mind-set, without reducing traits observed to bad parenting. Once the field accepted traits as something inborn to the individual, the door was opened to genuine studies of psychobiology and personality.
We can now look at Zuckerman’s line of inquiry from the context I have sketched out: If we accept as a premise that nature plays a major role in personality, what is that role exactly, and how is it played out? Zuckerman grapples with this complex issue as gamely and clearheadedly as can be expected, given the current state of our knowledge.
When we consider psychopathology through Zuckerman’s perspective, we can see that
most forms of psychopathology, particularly the personality and anxiety and mood disorders, can be conceptualized in terms of specific patterns of personality dimensions…. If this is true, then personality and psychopathology probably share certain kinds of psychobiological characteristics. Neuroticism, for instance, seems to be a predisposing trait for anxiety and mood disorders, and impulsive sensation seeking and aggression are found as traits from which antisocial personality develops. (p. xii).
If traits are grounded in biology, as Zuckerman argues, then psychopathology is as well. This is a profound thought with far-reaching consequences.
For those familiar with the predecessor to the book under review, Zuckerman notes that the first edition of his book was based on a “levels approach to personality…that attempts to explore all levels of personality, from the genetics to the trait with stops at the neurological, biochemical, physiological, conditioning and behavioral levels of explanation” (p. ix). The present edition emphasizes human psychobiology, with only a few animal models included (p. x).
Two major strengths Zuckerman brings to this text are his command of the literature and his ability to explain matter of factly the major lines of inquiry. Zuckerman has that rare facility to explicate the significance of a body of work simply and cogently, to focus on what it contributes and the limit of its scope. The reader experiences the pleasure of chatting with a master of his area without being bogged down with detail or overwhelmed with information.
The audience for this book is advanced students of personality—undergraduate or graduate students and instructors of personality. Because of the narrowness of its focus, the book would not do as a text in personality, but it would be a wonderful supplementary text for students who want to explore biological influences. For those who value an extensive bibliography, I estimated 620 references, including some as recent as 2003, and 33 references starting in 1969 to works of which Zuckerman was lead author. Zuckerman’s credentials as an expert who has been involved in the field for many years are thus evident.
Diligent in his exploration of the biology of personality, Zuckerman leaves us with a much clearer articulation of the nature–nurture issues. Just as Skinner (cited in Schultz, 1981), Patterson (1977), and others have demonstrated that nurture can be critical in understanding human behavior, Zuckerman balances the discussion and demonstrates that we cannot ignore or unduly diminish nature either.
From my perspective as a psychologist interested in personality assessment, Zuckerman’s work stimulates some interesting associations. For sure, personality assessment should incorporate a five-factor assessment protocol, which researchers could combine with more traditional personality instruments, such as the Millon Clinical Multiaxial Inventory (Millon, Millon, & Davis, 1994); the Thematic Apperception Test; the Rorschach; and autobiographical memory assessment systems, such as The Early Memories Procedure (Bruhn, 1989). Of course, the field should also consider an evaluation of biological variables known to affect personality. Zuckerman’s work helps us to peer into the future and see possibilities unimagined 50 years ago in the field of personality assessment. Any truly excellent text stimulates thought and, one hopes, research. By this criterion, Zuckerman’s is an excellent text.