We must recollect that all of our provisional ideas in psychology will presumably one day be based on an organic substructure.
—Sigmund Freud
How does the brain give rise to the mind? Where do the brain and mind meet, and by what means do they interact with one another? These are difficult questions—so difficult, in fact, that the common reaction is to focus on either the mind or the brain and act as if the other is irrelevant (Blass & Carmeli, 2007; Pulver, 2003). The problem with this approach is the barrier it creates to understanding that the human experience of brain and mind is essentially a unified process (Cobb, 1944). Neurology and psychology are simultaneously pushed apart by academic and intellectual politics while being drawn together by their common psychobiological foundation. The entangled histories of neurology and psychology reflect the push and pull of these powerful opposing forces (Ellenberger, 1970; Sulloway, 1979).
Freud started out as a rebel, a neurologist curious about the mind. I suspect he was frustrated with the mind–brain partisanship of medical school, and longed to work with others who shared his interests. At the age of 29, Freud won a traveling fellowship to spend the fall and winter of 1885 at the Salpêtrière Hospital on the left bank of Paris. The choice of the Salpêtrière was based on the reputation of Professor Jean-Martin Charcot, a man considered an expert on both mind and brain. In Charcot, Freud sought a teacher who was well established, confident, and unafraid of the no-man’s-land between mind and brain. One can imagine Freud’s excitement as he walked the streets of Paris on his way to meet the great man, a possible kindred spirit.
Charcot specialized in patients suffering from what was then called hysteria. These patients had symptoms, such as seizures or paralysis, that mimicked neurological illnesses but were without apparent physical cause. A classic example is a condition called glove anesthesia, in which feeling is lost in one or both hands beginning at the wrist. In these patients, the hands appear to take on symbolic significance; perhaps they have been used to commit some taboo act that triggered overwhelming guilt or fear. It was believed that a conflict within the mind was converted into a bodily symptom.
The 1880s were also a time when the ability of the subconscious mind to control behavior (as demonstrated through hypnosis) burst into popular awareness. Charcot used hypnosis during clinical demonstrations to illustrate his emerging theories about mind–body interactions. The months Freud spent at Salpêtrière with Charcot had a profound effect on him. He came to believe that hidden mental processes do indeed exert powerful effects on consciousness, and that hysterical symptoms result not from malingering or feigning illness, but from the power of the unconscious mind embedded within the neural structures of the brain. Hysteria, from this perspective, reflected the capacity of traumatic experience to reorganize the brain and disrupt conscious experience. Dissociative splits between consciousness and behavior demonstrated to Freud that the brain is capable of multiple levels of conscious and unconscious awareness. In the decades to come, he would explore the use of language, emotion, and the therapeutic relationship to reconnect them. Freud returned to Vienna in February 1886, and opened his own clinical practice 2 months later. Despite his entry into the medical establishment, he continued his rebellion later that year with the presentation of a paper on the existence of hysteria in males. Deeply fascinated by the unconscious, Freud remained its most ardent explorer until his death in 1939.
In the years following his residency at Salpêtrière, Freud expanded on Charcot’s thinking in many significant ways. He placed the unconscious in a developmental context by tracing the genesis of hysterical symptoms to childhood experiences. He came to believe that hysterical patients suffered from the unconscious emotional aftereffects of repressed childhood memories. Furthermore, Freud connected the development of the individual to the evolution of the species. Influenced by the ancient idea that we contain within us the biological history of our primitive ancestors, he included the importance of instinctual drives such as sexuality, rage, and envy in his developmental theories. Freud believed that beneath our civilized exteriors, there exists within us a more primitive being, accounting for many of the contradictions of modern “civilized” behavior.
Freud argued that in order to understand who and what we are, we need to understand the primal unconscious elements of experience. He called this the id—the primitive and uncivilized life energy that we share with our reptilian and mammalian ancestors. This concept was met with understandable hostility by Freud’s repressed and rational contemporaries. At that time, physicians were pillars of European culture, highly invested in their superiority over the animal kingdom and steadfast in their right and obligation to subjugate the “primitive” people of the world. Needless to say, linking civilized humans to animals (to say nothing of his idea that children have sexual desires) made Freud and his theories scandalous in respectable circles.
Freud’s Abandoned Project
The seemingly irreconcilable dichotomies and paradoxes that formerly prevailed with respect to mind vs. matter…become reconciled in a…unifying view of mind, brain, and man in nature.
—Roger Sperry
In the late 1800s, the doors to the microscopic world of the nervous system opened for the first time. Technical improvements in the microscope and newly developed staining techniques led to the discovery of both neurons and the synapses through which they communicate. The existence of synapses revealed that the nervous system is not a single structure, but instead is made up of countless individual processing units. Furthermore, that humans shared these neurons with all other living creatures supported the Darwinian idea of our common ancestry with other animals. Around this same time, the work of Wernicke and Broca showed that specific areas of the brain were responsible for different aspects of language. The dual neuroanatomical notions of synaptic transmission and the localization of specific functions to different areas of the brain provided rich theoretical soil for new ways of understanding the brain.
Inspired by Darwin, Charcot, and the opening of the microscopic neural world to investigation, Freud wrote The Project for a Scientific Psychology (Freud, 1968). In The Project, he postulated that what we witness of conscious and unconscious behavior is organized by and stored within the brain’s neural architecture. As part of this work, he drew simple sketches of interconnecting neurons to represent human impulses, behaviors, and psychological defenses. These sketches depicted the interactions among drives, the organs of the senses, and mechanisms of inhibition. According to his colleagues, Freud became obsessed with the idea of constructing a neurobiological model of the mind (Schore, 1997b). Despite his enthusiasm, Freud realized that his dream for psychology to be based in an understanding of the nervous system was far ahead of its time, and at odds with prevailing religious beliefs and medical dogma. For these and other reasons, he suppressed the publication of The Project until his death.
Perhaps Freud kept the Project to himself because he feared that it would be relegated to the same sort of obscurity as the case of Phineas Gage. Gage, a 19th-century railroad foreman, had a metal bar pass completely through his head as a result of an accident, causing the destruction of the middle portions of his frontal cortex. This particular area of the brain has since been shown to be involved with judgment, planning, and emotional control. Although Gage had no specific motor or language deficits, those who knew him said that “Gage was no longer Gage” (Benson, 1994). His emotionality, relationship abilities, and the quality of his experience were all dramatically altered. Because Gage’s symptoms involved his personality and emotions, the publication reporting his case received little attention for most of the 20th century. Not only was it outside the realm of behaviors that neurologists felt comfortable addressing, but there was also a bias against relating human personality to neurobiological mechanisms (Damasio, 1994).
Freud, the neurologist, became all but forgotten as his psychological theories moved further and further from their biological roots. He chose instead to utilize the more palatable and accessible metaphors of literature and anthropology to provide the primary vocabulary for psychoanalysis. Unfortunately, Freud’s shift from the brain to metaphors of mind opened psychoanalysis to all sorts of criticism throughout the 20th century. Metaphors such as the Oedipal and Electra complexes were seen as contrived fictions, shielding them from scientific evaluation. Perhaps Freud anticipated that in the future, psychoanalysis would eventually be integrated with its neurobiological substrates. This would only happen when the time was right for a synthesis based in an equal partnership of both sciences (Pribram & Gill, 1976).
The time for such an integration has arrived, and respect for psychological processes have taken a strong enough hold within both the scientific community and general culture that we can avoid a reduction of the mind to basic biochemical processes. On the contrary, an appreciation for the structures and functioning of the brain by nonneurologists has become the norm. It is in this spirit that we turn our attention to ways of thinking about the brain that enhance our understanding of human experience. We begin with a model of the brain that provides a bridge between the fields of neuroscience, evolution, and the origins of the unconscious.
The Triune Brain
He who joyfully marches in rank and file…has been given a large brain by mistake, since for him the spinal cord would suffice.
—Albert Einstein
In the 1970s, the neuroscientist Paul MacLean presented a theory that emphasized the conservation of more primitive evolutionary structures within the modern human brain (MacLean, 1990; Taylor, 1999). MacLean called his idea the triune brain. Very much in line with the theories of Darwin and Freud, it provides an evolutionary explanation that may account for some of the contradictions and discontinuities of human consciousness and behavior.
MacLean described the human brain as a three-part system that embodies our evolutionary connection to both reptiles and lower mammals. Think of it as a brain within a brain within a brain, with each successive layer devoted to increasingly complex functions and abilities. At the core is the reptilian brain, relatively unchanged through evolutionary history, responsible for activation, arousal, homeostasis, and reproductive drives. The paleomammalian brain (or limbic system), which is central to learning, memory, and emotion, wraps around the reptilian brain. The highest layer, the neomammalian brain or cerebral cortex, organizes conscious thought, problem solving, and self-awareness (MacLean, 1985).
MacLean suggested that our three brains don’t necessarily communicate or work well together because of their differing “mentalities” and the fact that only the neomammalian brain is capable of consciousness and verbal communication (MacLean, 1990). This is a fundamental issue that connects evolution, neuroscience, and psychotherapy. What Charcot and Freud called dissociation and hysteria could well have been the result of inadequate integration and coordination among these different, cohabiting brains. MacLean’s description of the nonverbal reptilian and paleomammalian brains unconsciously influencing processing in the neomammalian brain roughly parallels Freud’s distinction of the conscious and the unconscious minds.
The model of the triune brain serves the valuable function of providing a connective metaphor among the artifacts of evolution, the contemporary nervous system, and some of the inherent difficulties in the organization of human experience. This conservation of our evolutionary history alongside our modern neural networks confronts the therapist with the challenge of simultaneously treating a human, a horse, and a crocodile (Hampden-Turner, 1981).
Ah, If Only It Were So Simple!
The large brain, like large government, may not be able to do simple things in simple ways.
—Donald Hebb
A superficial reading of MacLean’s work might lead us to the idea that each layer of the triune brain evolved independently and sequentially, and that they all cooperate in a hierarchical fashion like a military chain of command. This is clearly not the case. In reality, the reptilian and paleomammalian brains have continued to evolve alongside the neomammalian brain. Earlier structures are not conserved “as is” from past generations, but also undergo a process of exaptation—the modification of earlier evolving brain structures for new applications in networks dedicated to alternative or more complex functions (Cacioppo & Berntson, 2004). Thus, all three layers continue to evolve along with the emergence of ever more complex vertical and horizontal neural networks. This conservation and modification of neural networks has led to an amazingly complex brain capable of a vast array of functions from monitoring respiration to performing mathematical computations. This makes understanding functional neuroanatomy from a study of the contemporary brain quite a challenge.
An example from space exploration may prove useful in understanding the neuroanatomist’s dilemma. When Apollo 13 approached the moon, difficulties with the air supply system left the crew with just a few hours of oxygen (Lovell & Kluger, 1994). In the face of this crisis, scientists on earth removed nonessential components from a mock spacecraft and constructed a new air supply system. Pieces of upholstery, plastic bags, duct tape, and electrical wiring were used in innovative ways to serve new functions. The instructions on how to build this makeshift device were then conveyed to the Apollo 13 crew. This scenario is much closer to the crafting of the modern brain than imagining an engineer sitting down with a blank sheet of paper. An engineer of the future presented with this bootstrapped air purification system would have a difficult time figuring out what it is and why it was built the way it was. Although there are obvious differences between the Apollo 13 scenario and natural selection, both are examples of a pragmatic adaptation with existing materials to an environmental crisis.
The multiple roles played by the cerebellum offer a prime example of both neural conservation and exaptation. The cerebellum is a primitive brain structure. At its core is the vermis, centrally involved in balance. In fish, the vermis helps them to swim upright. In humans, it coordinates vestibular functioning and helps us to sit up and walk without falling. During evolution, as our brains and bodies became more complex, the cerebellum expanded to coordinate gross and then fine motor movements—a logical development for a structure initially at the core of the ability to swim. In an interesting and surprising twist, the later-evolving portions of the cerebellar lobes are involved in the organization and coordination of language, memory, and reasoning (Schmahmann, 1997). It appears that the cerebellum’s ability to process, sequence, and organize vast amounts of sensory-motor information was utilized by the evolving brain as part of the neural infrastructure of higher cortical processes.
Just as balance and motor behavior require constant monitoring of posture and the inhibition of unnecessary and distracting movements, so, in their own ways, do attention, concentration, memory, and language. The same timing mechanisms involved in locomotion seem to have been conserved for sequential processing in thought and language. Although the cerebellum is considered a primitive brain structure, its evolution involved vertical networking with most of the cortex, suggesting that the vertical networks that connect the horizontal layers of the triune brain may serve as clues to its evolutionary history (Alexander, DeLong, & Strick, 1986; Cummings, 1993).
In addition to horizontal and vertical networks, evolution has also selected for increasing differentiation between the left and right hemispheres. Certain areas of the brain have become specialized for specific skills, such as language and spatial abilities. Still other areas, such as those in the prefrontal cortex, serve to organize and control the activity of multiple other regions. Keep in mind that the brains of men and women also have many differences and that the brain changes as we grow up and grow older (Cozolino, 2008). Many of these differences are especially important to the processes of attachment and affect regulation so central to psychotherapy.
Neural networks relevant to psychotherapy exist throughout the brain—some are evolutionarily primitive, others developing more recently. Some are fully functional from birth, while others take decades to mature. This is why an understanding of both evolution and development is vital in capturing the full picture of human experience.
The Interpersonal Sculpting of the Social Brain
It is difficult to give children a sense of security unless you have it yourself. If you have it, they catch if from you.
—William Menninger
The theory that ontogeny recapitulates phylogeny refers to the concept that the evolution of the species is recreated in the gestation and development of each individual. To use MacLean’s terms, we pass through the reptilian and paleomammalian stages before we develop into a fully human being. Although the theory of recapitulation is in most ways incorrect (Gould, 1977), some interesting parallels exist between our evolutionary history and the process of human development.
At birth, the reptilian brain is fully functional and the paleomammalian brain is primed and ready to be organized by early experiences. The cortex, on the other hand, continues to slowly grow into the third decade and matures throughout life. Thus, much of our most important emotional and interpersonal learning occurs during our early years when our primitive brains are in control. The result is that a great deal of learning takes place before we have the necessary cortical systems for explicit memory, problem solving, or perspective. Consequently, many of our most important socioemotional learning experiences are organized and controlled by reflexes, behaviors, and emotions outside of our awareness and distorted by our immature brains. To a great extent, psychotherapy owes its existence to these artifacts of evolution and development.
The slow development of the cerebral cortex maximizes the influence of experience in building the brain. That so much of the brain is shaped after birth is both good and bad news. The good news is that the individual brain is built to survive in a particular environment. Culture, language, climate, nutrition, and parents shape each of our brains in a unique way. In good times and with good-enough parents, this early brain building will serve the child well throughout life. The bad news comes into play when factors are not so favorable, such as in times of war or in the case of parental psychopathology or separation (Benes, Taylor, & Cunningham, 2000). The brain is then sculpted in ways that assist the child in surviving childhood but may be maladaptive later in life. It is in these instances that a therapist attempts to restructure neural architecture in the service of more adaptive behavior, cognition, and emotion. Building the human brain is vastly complex. Rebuilding it is a difficult and fascinating challenge.
A portion of the brain called the anterior cingulate—centrally involved with maternal behavior, nursing, and play—appears in the evolution of early mammals (MacLean, 1985). Before this, animals had to be prepared to survive on their own at birth. Good examples are newborn sea turtles that hatch from their eggs high on a beach and make a mad instinctual dash toward the ocean. With the evolution of maternal care, children are allowed to develop more slowly within a supportive, scaffolding environment. In the course of evolution, primates have experienced increasingly longer periods of maternal dependence. This luxury allows for the evolution and development of more complex brains, as well as an increasing impact of parenting and early experiences on how the brain is built.
Konrad Lorenz (1991) found that geese imprint (bond to attachment figures) during a limited period of time soon after birth. If baby geese saw Lorenz first, they would follow him as if he were their mother. Lorenz also found that when these geese reached sexual maturity 2 years later, they would “fall in love” with the kinds of geese they had been exposed to during their imprinting period. He even noted that a baby goose, which originally imprinted on him, fell in love with a human girl from the next town when he reached sexual maturity and would fly there to see her. These early experiences seemed to be permanently etched into the brains of Lorenz’s geese.
This principle of imprinting can be seen in humans in the more flexible and complex form of attachment schema. The early interpersonal environment may be imprinted in the human brain by shaping the child’s neural networks and establishing the biochemical set points in circuitry dedicated to memory, emotion, safety, and survival. Later, these structures and processes come to serve as the infrastructure for social and intellectual skills, affect regulation, and the sense of self.
Prolonged dependence in childhood has allowed for the development of a neocortex so complex that we have become capable of spoken and written language, self-consciousness, and the construction of both private and social selves. Although these abilities create tremendous possibilities, brainpower does have its downside. We are now also capable of becoming anxious about things that will never happen, depressed by imagined slights, and saddened by potential losses. Our imaginations can simultaneously create exciting new worlds, as well as the fears that prevent us from living in them. It is obvious that despite the evolution of consciousness and rationality, our primitive emotional brains and their early development continue to exert a great deal of influence over us.
Summary
Although Freud began his career attempting to create a brain-based psychology, the theories and technology available to him did not allow him to carry out this project. Various ways of thinking about the brain (like MacLean’s), although limited, provide models that bridge the gap between psychology and neurology. Evolution’s legacy is a complex brain, vulnerable to a variety of factors that can disrupt the growth and integration of important neural networks. The field of psychotherapy has emerged because of the brain’s vulnerability to these developmental and environmental risks. But how can psychotherapists synthesize and incorporate both the mind and the brain into our work? The following chapter presents a model of neural networks, how they develop, and how we attempt to alter them during treatment. It is from this perspective that we will then examine the relevance of the nervous system to our work.