When I trained as a clinical psychologist during the 1980s at a well-regarded American university, there was little mention of neuroscience. Given the brain's central role in human experience, I found this unsettling. After a few years in practice I began to explore the seemingly empty scientific space between the brain and psychotherapy.
I discovered that before Sigmund Freud founded psychoanalysis, he was deeply interested in neurology. In a paper entitled "Project for a Scientific Psychology," he proposed to examine the neural structures underlying human experience. Freud included crude diagrams of neural
networks representing our inner experiences, defense mechanisms, and some possible causes of mental illness.
Hostile reactions from his colleagues convinced Freud to suppress the paper, which was published only after his death fifty years later. During the 20 th century, psychoanalysis and other branches of psychotherapy parted company with neurology, developing a rich metaphoric language of the mind that paid little attention to the brain and nervous system. Simultaneously, the neurosciences built a deep store of knowledge about the brain's relationship to observable behavior.
Cultural and religious beliefs also contributed to this scientific division by holding that conscious experience must somehow arise and exist independently of the human body. This dualism of human spirit and physical body implied that brain-based explanations for problems affecting motor movement and language were possible, but that personality, feelings, and beliefs existed in the realm of the spirit. Thus, psychotherapy and the neurosciences traditionally maintained their own departments, world-views, and languages, viewing each other with suspicion and distrust.
Another barrier to their collaboration has been that the brain is widely viewed as a static entity, determined by genetic preprogramming and early childhood experience. Based on this dogma, students of both fields were taught that neural plasticity, or the ability of the nervous system to grow and change, was extremely limited after childhood. Freud had to abandon this pessimistic view of the brain to pursue the idea that his "talking cure" could alter neural connections and change the nature of psychological experience. He was right to do so.
The human brain and nervous system, it turns out, are built and sculpted, neuron by neuron, through the interaction of our particular genes and experiences, in what is called use-dependent development. We now know, for example, that all learning and memory are encoded within the nervous system, and that it is this learning that organizes the neural architecture and functioning of the brain. Every experience, from moving a toe to deep states of meditation, is stored in and organized by the electrochemical signaling within and between neurons. Changing our minds, by definition, changes our brains.
During childhood, the growth and organization of the brain occurs in parallel with the rapid development of a wide range of skills and abilities. But the brain continues to react to its environment and remains plastic, to some degree, throughout life. Researchers are currently focusing on the underlying genetic and biochemical processes that generate new neurons and stimulate existing ones to change and grow. There is hope across all clinical fields that deal with disorders of the nervous system that these discoveries will lead to greater understanding of brain functioning and radically improved treatment.
Psychotherapy attempts to create a learning environment that targets specific skills and abilities--organized by the same neural systems that neuroscientists are in the process of discovering--to induce changes in thinking, feeling, and behavior. Obviously, this new perspective radically re-defines psychotherapy. If the goal of therapy is to alter thoughts, behaviors, and feelings, then psychotherapists are attempting to change the physical architecture of the brains of their clients.
If all of this is true, psychotherapy succeeds to the extent that it activates and enhances the lifelong processes of neural plasticity. From this perspective, psychotherapy is an enriched interpersonal environment, tailored to encourage the growth and integration of neural networks regulating memory, cognition, emotion, and attachment. Despite psychotherapy's historical lack of attention to the brain, the invisible hand of neural plasticity has guided its development--and the therapist has always been an unsuspecting neuroscientist.
Findings in neuroscience are now beginning to support this connection. For example, psychotherapists' supposedly "unscientific" use of language and emotional attunement may actually provide the best medium for some types of neural growth and integration. The human brain has evolved in tandem with spoken language in social contexts, so it is logical to believe that emotion-laden interpersonal dialogue may well stimulate the brain to learn. Interpersonal neurobiology, a new field combining developmental psychology, evolutionary biology, and genetics, seeks to understand how relationships throughout life are translated into the structure and function of the nervous system.
Our research tools and theories remain primitive relative to the complexity of the human brain and there are few definitive answers about the causes and treatment of mental illness. Future advances will require the interaction of laboratory research, clinical case studies, and the imagination of creative thinkers. Freud's brand of psychoanalysis has fallen on hard times, but he would be the first to endorse the widening dialogue between psychotherapy and neuroscience.