Brain-Based Therapy with Adults

Evidence-Based Treatment for Everyday Practice

John B. Arden, Lloyd Linford

• Publisher: Wiley
• Year: 2008
• ISBN:
  9780470467299
• Edition: 1
• Topic: Psychology
• Subtopic: Clinical Psychology
• Index: Psychology

Brain-Based Therapy with Adults: Evidence-Based Treatment for Everyday Practice provides a straightforward, integrated approach that looks at what we currently know about the brain and how it impacts and informs treatment interventions. Authors John Arden and Lloyd Linford, experts in neuroscience and evidence-based practice, reveal how this new kind of therapy takes into account the uniqueness of each client. Presentation of detailed background and evidence-based?interventions for common adult disorders such as anxiety and depression offers you expert advice you can put into practice immediately.

CHAPTER 1

How We Change

The average species on Earth lasts for only about four million years, so if you wish to be around for billions of years, you must be as fickle as the atoms that made you. You must be prepared to change everything about yourself—your shape, size color, species affiliation, everything—and to do so repeatedly. . . . So at various periods over the last 3.8 billion years you have abhorred oxygen and then doted on it, grown fins and limbs and jaunty sails, laid eggs, flicked the air with a forked tongue, been sleek, been furry, lived underground, lived in trees, been as big as a deer and as small as a mouse, and a million things more. The tiniest deviation from any of these evolutionary shifts, and you might now be licking algae from cave walls or lolling walruslike on some stony shore or disgorging air through a blowhole in the top of your head before diving sixty feet for a mouthful of delicious sandworms.

—Bill Bryson, A Brief History of Almost Everything

AS PSYCHOTHERAPISTS, WE think a lot about how people change. Our ideas on the subject shape how we practice our professional arts. In many psychotherapies, there is a moment when the patient looks at us and poses the question directly: “Do you think people can change?” This is usually a way of asking “Do you think I can, and that I will?” Some evidence suggests that the average psychotherapist has more than the usual level of conflict or unhappiness in his or her own family background. Maybe that is what inspires us to try to transform a little of other people’s unhappiness into security and contentment and to believe that the answer to the question about can I and will I change is yes.

In our time, three or four relatively independent traditions in science are converging on clinical psychology. By being aware of their intersection,

psychotherapists can back up their optimism with solid evidence that people do change and that therapy is effective in helping them do so. Neuroscience, genetics, attachment studies, psychotherapy research, and studies of mindfulness meditation all play a part. In this book we rely on research in neuroscience, psychotherapy research, cognitive and psychodynamic psychology, attachment research, and evidence-based psychotherapeutic practices. The model we present incorporates many assumptions on which psychotherapy has been based for the last 100 years or so—about the importance of the therapeutic alliance and particular techniques with specific disorders. What is relatively new is the emphasis we place on attachment and neuroscience. We argue that a personal and rather mysterious decision by Sigmund Freud separating psychology from biology has had long-lasting and deleterious effects.

Some commentators (Cozolino, 2002) have suggested that psychotherapy could not have survived as a branch of neurology, which is to say that Freud had to cut the umbilical cord uniting the two. The point is well taken. However, Freud’s decision also led to a schism in the mental health field, in which psychology has viewed the mind as an entity independent of the brain and biological psychiatry tends to see the brain as if the mind were just a “ghost in the machine.” The latter view has been the dominant one in the “Pax Medica Era,” which we believe may be coming to an end. In this book, we would like to advance the assumption that the mind and the brain are different manifestations of a single set of processes—that mind and experience shape the brain’s structure. That is how we change.

NURTURED NATURE

In contemporary neuroscience, the causes of even basic psychological phenomena are often far from simple ones. The genetic contribution to brain functioning is a case in point. Genes commonly are taken as the most deterministic, least environmentally influenced element in our lives—for all intents and purposes as “nature.” In fact, this is a serious overstatement, because the gene itself, while influencing behavioral potential, is in turn endlessly shaped by the environment. An obese patient who says “I got the gene for my waist size from my father!” means to say he is not responsible for his eating habits any more than he is for his brown eyes. His alibi needs updating. While genes influence our vulnerability not only to obesity but to various psychological disorders as well, people’s experience typically determines whether pathogenic genes are expressed and result in an actual disorder.

Every cell in the human body contains the same set of genetic instructions found in the fertilized egg’s DNA. What makes one cell become a neuron and another a part of the bones in the hand? To be expressed, the DNA molecule must be opened up so that it can be copied and transmit its genetic information into proteins within the cell. In practice, the cell’s DNA is selectively “unpacked,” and accordingly, only some genes are expressed. The chemical regulators of the DNA form an epigenetic system that determines what role (if any) a particular gene will have. Animal studies have shown that epigenetic factors are affected by environmental influences such as early abuse or neglect by a parent (Higgins, 2008) and in humans, reactions to environmental trauma such as famine can be transmitted from one generation to another.

Genes are an important factor in understanding how we change. Under certain conditions, they constitute a major influence in the development of such psychological disorders as schizophrenia (where estimates of the heritability of this disorder range as high as 80%), autism, obsessive-compulsive disorder, and social anxiety disorder, among other disturbances. This happens where the individual carries the necessary gene or genes and where the epigenetic system permits the gene to be expressed. The unpacked part of the DNA string is copied, producing a complementary molecule of messenger RNA (mRNA) through a process called transcription. The RNA in turn produces proteins in the cell through translation. Through transcription and translation, information in an expressed gene becomes the template for the cell’s functions. But whether the gene is allowed to express itself is subject to environmental influences.

Like Escher’s famous lithograph of a hand drawing itself, genes and environmental responsiveness are cocreating processes. Minor changes in either the environment or the transcription and translation processes may result in significantly altered functioning. Gene expression is fundamental to synaptic plasticity, the process that allows the brain to remodel itself, to change how it functions in order to adapt to novel or changing conditions (Black, 1998; Kandel, 2000). Recent science suggests an übergenetic, or epigenetic, system that changes in response to environmental exposure (e.g., to famine) and has the power to switch the expression of specific genes on or off. Although the percentage varies widely depending on the precise gene, roughly speaking, genes control about 50 percent of the variance in most traits. People who carry a gene that influences the trait of shyness are much more likely to feel shy and behave accordingly than people who lack this predisposition if their shy gene gets expressed. Inevitably the gene’s expression will be moderated by environmental influences. A child with a tendency to be shy may learn to modulate her shyness through the support and encouragement of her parents (Kagan, 1998); and adults can modify such a disposition through many different kinds of experiences, including therapy. A person with a family history of affective disorders, who carries a gene that predisposes him to psychopathology, may never develop depression or bipolar disorder and can enjoy a reasonably happy life. A child growing up in an extended and encompassing family of shy people who struggle with a high incidence of major depression, however, will be challenged on both the nature and nurture fronts.

Early studies of heredity assumed that siblings reared in the same families are exposed to highly similar environments and that differences between siblings must be caused by genetic variation. More recent research shows that things are not that simple. Dunn and McGuire (1994) compared family environments and noted unique factors that often exerted significant influence on development, such as different friends and school experiences. Siblings, even identical twins, do not inhabit the same environments, and even shared experiences may be interpreted quite differently, which in turn may prompt the influential people in their environment—including their parents—to interact with them differently than with their siblings (Pike & Plomin, 1996).

Each step of the way, genetics and experience mutually influence development. Genes set the range of possible developmental paths; experience stimulates the individual to react in ways that are based on learning; and learning changes the likelihood of genetic expression (Guzowski et al., 2001). For example, the manner in which parents respond to their child’s temperament produces feedback that results in shaping the growth, interconnections, and massive “pruning” (or programmed cell death) of the child’s neurons. When a newborn baby first emerges from his mother’s womb, he’s likely to have twice as many neurons as the obstetrician or midwife assisting in the delivery. Over the course of childhood and through adolescence, these excess neurons die off based in part on how often they are stimulated by the external environment and other neurons. In this way, interplay between a child and parent changes the child’s behavior and the influence of gene expression. We explore the interactions and effects of temperament and attachment in this book’s companion volume, Brain-Based Therapy with Children and Adolescents.

Gene expression, experience, mental activity, and behavior are intertwined and form a transactional set of processes (Rutter et al., 1997). The growth of new synapses (and even new neurons) gives us the capacity to nurture nature—because the functional relationships between neurons play such an important role in determining who we are and how we behave (LeDoux, 2002). In other chapters we explore some of the subtle ways that nature and nuture interplay to produce the kinds of problems found in the panoply of mental disorders cited in the fourth edition of the Diagnostic and Statistical Manual of Mental Disorders. For the time being, let us turn to an examination of how these interactions between genes and environmental “triggers” produced the human brain in the first place.

EVOLUTIONARY BACKGROUND

Our genes are the historical record of minute changes in the DNA of our evolutionary ancestors passed down from one generation to another. Comparative studies of human and nonhuman genomes suggest that we share an enormous amount of this heritage with other mammals and almost all of it with the nonhuman primates. Human DNA is 96% identical to the DNA of chimpanzees (Lovgren, 2005). In the awesome timeline of evolutionary history, Homo sapiens arrived only recently. Although the common ancestors of humans, the great apes and the Old World monkeys, are believed to have made their first appearance 63 million years ago (and were still around as recently as 13 million years ago), humans have been on the scene for a small fraction of that time. Homo sapiens idaltu, dating from about 160,000 years ago, is the oldest known anatomically modern human.

According to one model (known as the Lake Toba Catastrophe theory), between 50,000 and 70,000 years ago a super-volcanic event reduced the world’s human population to as few as 1,000 breeding pairs (Ambrose, 2001). With only a few thousand individuals surviving, humans became an endangered species on the brink of extinction. This radical restriction of the breeding population may be why human DNA is remarkably homogenous across different settings. Tumultuous environmental change would have favored genetic shifts in our ancestors’ capacities for rapid learning and adaptation. The capacity for rapid adaptation to changing conditions—the capacity for flexible change—was privileged.

Even before the Lake Toba volcanic event, our ancestors’ brains had begun to expand, especially the prefrontal cortex. The growth of the neocortex and associated structural and functional changes in the subcortical brain centers took place relatively slowly from about 400,000 years ago until about the time of the Lake Toba events. From 50,000 years ago onward, the record of fossils and cultural artifacts shows startlingly rapid change, suggesting either a dramatic genetic shift or the cumulative effects of interactions between genetically mediated brain potential and an environment in which human culture in itself started to play a dominant role in human evolution. Our ancestors relatively suddenly began producing ever more refined human artifacts, beyond the early fashioning of stone tools. After 50,000 years ago, there is evidence that our progenitors began burying their dead, making animal hides into clothing, and painting symbolic art on the walls of their dwellings. The essential capacities of the modern human brain rather suddenly came on line for creatures confronting massive environmental change.

Paleoanthropologists believe this “great leap forward” could only have come about as a result of changes in the neural architecture underlying our ancestors’ behavior and capacity for internalized thought in the human neocortex. Of all animal species, humans have the largest prefrontal cortex as a proportion of total brain volume. About 20% of the human brain is comprised of frontal lobes; by contrast, frontal lobes comprise about 3.5% of feline brain volume. The most recent addition to our evolutionary development, the frontal lobes are also the last to mature in individual humans, with development not complete until sometime in the third decade of life. The prefrontal cortex (at the forefront of the frontal lobes) gives us many of our most complex human cognitive, behavioral, and emotional capacities. It endows us, for example, with the ability to develop and act on a moral system (Dolan, 1999). The prefrontal cortex (PFC) lets us set aside our own agendas and reflect on the needs of others. It is associated with our subjective experience of empathy. When the PFC is damaged, people are likely to engage in behaviors that are antisocial and impulsive or not engage in purposeful behavior at all. At a time when human populations were dispersing out of Africa, a larger PFC constituted an indispensable asset in enhancing the richness of social bonds and attachment.

Underneath the cortex there were other changes in the brains of our immediate ancestors. “Lower brain” centers, such as the limbic areas and the cerebellum, changed to support the growth of the human behavioral and emotional repertoire. The cerebellum, an area specialized for motor control in other mammals, also performs sophisticated organizing functions in the human brain, working in tandem with frontal lobes (Grigsby & Stevens, 2000).

The motor area of the brain adjacent to the tongue and lips in the left frontal lobe (now called Broca’s area) coevolved with the ability to produce speech (Fuster, 1997), enriching social relationships and internal cognitive processes. Like a new tool, speech changed what the brain could do, and, as we later demonstrate, heightened brain activity leads to further changes in neural architecture.

As our ancestors were subjected to radical new pressures from sudden climate change and as genetic shifts made new behaviors possible, the advantages of social life became even more pronounced for humans. The human brain has a vested interest in the expression of our genetic endowment for empathy, the human ability to “feel” what others are thinking and feeling, because mindsight is prerequisite to the brain’s very existence. Human infants have very large heads and are born with brains that require, as it were, much home assembly. To survive, the brain must have relationships with caring, attentive, and deliberate caregivers who see the needs of their young as more important than their own. Loving, appreciating the development of those we love, and resolving interpersonal problems with those we are closest to has survival value for the brain. Human evolution has favored the development of these qualities over almost all others, because the survival of the brain itself depends on them.

John Bowlby (1969) applied this evolutionary perspective to observations of infants and children with their caregivers. Looking at the human infant as a young creature whose world is, for all intents and purposes, the maternal environment, Bowlby showed that newborns adapt out of Darwinian necessity to their mothers’ personality and circumstances. The infant’s capacity for creating and using relationships is carried in the brain’s genetic makeup. Within minutes of birth, infants show a preference for gazing at the human face and can imitate facial expressions such as opening the mouth and sticking out the tongue (Meltzoff & Moore, 1998). The infant’s hand grasps when something (such as another hand) is placed in its palm. Replete with clever neurodynamic mechanisms for intuiting the mental state of those around us, we are born to be shaped in the context of relationships. The cold evolutionary rationale for this phenomenon may well be that our ancestors faced catastrophic environmental change. Those endowed with a brain that could change rapidly, learn quickly, and maximize the advantages of social networking survived.

The ability to decipher subtle social cues is a contribution of the expanded PFC. The orbitofrontal cortex (OFC)—that part of the prefrontal lobes that lies directly above and behind the eyes—enhances the human capacity for social appraisal, allowing us to give complex social interactions an emotional value and think over the likely consequences of risky social moves before we act. Language lets us tell someone who was not there what we witnessed or what we heard from someone else about what he or she witnessed, vastly expanding the generalizability of individual experience. Together these faculties let us learn from other people’s stories as well as our own.

Figure 1.1 Lobes of the Human Brain

Astonishingly, the brain embodies within it the power to be changed by these stories, and this may be the human brain’s most valuable legacy. Elsewhere in this book we return to the discussion about the interplay of genes and evolutionary history and the difference that the frontal lobes have made in human history. Affect regulation, decision making, and attention are topics of enormous relevance to psychotherapy. But before launching into a more detailed account of what contemporary neuroscience has to tell us as psychotherapists about the brain, let us consider why we need to have this discussion at all. How did psychology and brain sciences become estranged in the first place?

REDISCOVERY OF THE BRAIN

Awareness of the astonishing adventure of our evolutionary past was lost to humanity until the late nineteenth century, when Charles Darwin’s Descent of Man, and Selection in Relation to Sex (1871) exhumed it. Darwin’s careful cataloging of how species such as the finches of the Galapagos adapted to food supplies and other environmental variables laid the foundation for our understanding of gene-environmental interactions in biological systems—a model that is at the heart of modern neuroscience. Similarly, his later theory that man and the nonhuman primates descended from common stock opened new fields of inquiry into our history as a species and the selective advantages bestowed by the human brain.

Figure 1.2 Environmental Selection of Biological Fitness

Darwin’s insig...