As the new columnist for “Science and Psychoanalysis,” my perspective will be highly personal—notes about science and the scientific literature that have come to my attention and that interest me as a psychoanalyst. It will also include issues at the interface of science and psychoanalysis—professional, political, cultural, educational, and other. I am limited by what comes to my attention, but would be happy to receive advice, suggestions (and not quite as happy, but happy enough, with criticism or complaint). I will try to be interesting, and as a result might spend more time at the boundaries than at the center.
I will start with experimental psychology, which it seems should be of great interest to psychoanalysts, but in fact has often turned out to be of little relevance. Psychoanalysts are concerned with important human themes— love, rage, identity, anxiety, conflict, among others. However, psychoanalysts often sacrifice precision and methodologic rigor because they believe these attributes are incompatible with the topics that interest them. Experimental psychologists insist on precision and rigor and, at least to psychoanalysts, often seem to sacrifice relevance in order to achieve them.
A recent study by a group at Oxford and Queen Square Institute of Neurology in London, reported in Science (vol. 305, issue 5685, 2004), provides refreshing evidence that it is possible to be both relevant and rigorous. The study addresses a question that has interested psychoanalysts since Freud: the origins of the feeling of ownership of one's own body. Analysts all know Freud's view, stated in “The Ego and the Id”—“The ego is first and foremost a bodily ego.”
H. Henrik Ehrsson and colleagues studied the neuronal counterparts of the feeling of ownership of the hand. They employed a well known perceptual illusion, hiding the subject's real hand while displaying a realistic rubber hand. They then stroked both the real and the rubber hands. In a brief time, subjects experienced the rubber hand as their own, but only if the positions of the two were visually aligned and the stroking was simultaneous.
They performed the experiment while conducting functional magnetic resonance imaging (fMRI) of the subjects' brains. This is a method for imaging the brain and studying the activity of different regions while the subject is engaged in mental activity. It is non-invasive, can be repeated multiple times without undesirable effects, and has fairly good spatial and temporal resolution (e.g., one can differentiate small parts of the brain that are relatively close together and follow changes over brief intervals of time). It has revolutionized neuropsychological research—the neuroscientist's equivalent of the telescope or microscope.
It was possible to identify those brain regions that “lit up” when the illusion led to the “feeling of ownership,” but not in response to the simple visual or tactile stimuli. The critical area was the premotor cortex, as part of a circuit including the parietal cortex and the cerebellum. “When the illusion arises, there is a change in the proprioceptive and tactile representations of the hand so that the somatic information from the hand matches the visual information.” The researchers conclude, “Multisensory integration in a body-centered reference frame is the underlying mechanism of self-attribution.”
In an editorial accompanying the paper, Matthew Botvinick at the University of Pennsylvania's Center for Cognitive Neuroscience points out that animal studies have shown that the premotor cortex contains neurons that respond to both touch and vision. They are activated not only by objects that touch or are seen touching the body, but even by objects seen approaching the body or approaching a tool that is being held by that part of the body. Thus the neurobiologists' “self,” like the psychoanalysts', includes a subjective mental representation that extends beyond the physical limits of the skin.
Botvinick closes, “Evaluating these possibilities…will require a willingness to engage phenomena that are, at least in part, irreducibly subjective. This willingness has been rare among experimentalists. [This] work… provides an encouraging indication that this attitude may be changing.”
Psychoanalysis has always been intrigued with the irreducibly subjective. The sense of self, the feeling of ownership of the body, is the kind of subjective experience, about which we theorize. Ehrsson, Botvinick, Science, and scientists are beginning to address these topics, attempting to “reduce” what can be reduced, and recognizing the importance of what cannot. It is vital that we remain engaged in the dialogue, learn from them, and share our insights with them.
It is an exciting time.
Robert Michels, M.D., is Walsh McDermott University Professor of Medicine and Psychiatry at Cornell University. He is a training and supervising psychoanalyst at the Columbia University Center for Psychoanalytic Training and Research.