Freud's Theory of the Mental and Modern Functional Imaging Experiments*

What relations are there between Freud's theories of the mind and modern functional brain imaging experiments? To anchor this question, we present two statements from an article by Mark Solms (1997) about consciousness in a recent Journal of the American Psychoanalytic Association.

First, Solms emphasized Freud's definition that “Mental processes are in themselves unconscious” (p. 683), arguing the relevance of this definition to modern controversies about brain/mind/consciousness. We are willing to accept a moderate form of this position, in which the unconscious is acknowledged to contribute significantly to mental processes.

The second quotation is less familiar: “psychoanalysis and PET scanning … study one and the same underlying object: the mental apparatus and its functions” (p. 691). We do not plan to discuss Solms's use of this identity in pursuit of consciousness. This statement is evocative and needful of comment particularly in a period of intense research in the neurosciences when functional magnetic resonance imaging (fMRI) and positron emission tomography (PET) methods have been experimentally localizing brain activities. These functional imaging methodologies map neurophysiological responses to cognitive, emotional, or sensory stimulations (Posner & Raichle, 1994; Raichle, 1998; Shulman, Blamire, Rothman, & McCarthy, 1993). The experiments are non-invasive and may be done repeatedly. The rapid progress made using these methods has encouraged widespread optimism about our ability to understand activities of the mind.