For most of the twentieth century, science and depth psychology occupied separate rooms and rarely talked. Neuroscientists studied the brain. Jungians studied the psyche. The assumption was that these were different territories and the conversation between them was mostly uncomfortable. Then Mark Solms walked into both rooms at once.
Solms is a neuropsychologist and a trained psychoanalyst — a combination that is rare enough to matter. What he set out to do in this landmark 1997 study was straightforward in concept and enormously difficult in execution: he wanted to know what happens to dreaming when specific parts of the brain are damaged. Not in theory. In actual patients — 361 of them, each with documented brain lesions, each interviewed about their dream life before and after.
What he found shook the prevailing assumptions about how dreaming works, and in doing so, quietly validated a great deal of what Jung had been saying about the unconscious for most of his career.
"Patients with damage to the part of the brain that generates REM sleep still experienced dreams. Moreover, patients in whom dreaming was abolished had damage to a completely different part of the brain."
— Mark Solms, summarizing his central findingWhat the Research Actually Found
The dominant assumption going into this research was that dreaming and REM sleep were essentially the same thing — that the rapid eye movement phase of sleep was where dreams happened, and if you understood REM, you understood dreaming. Solms' data dismantled that assumption methodically.
REM Is Not Dreaming
Patients whose brain damage disrupted REM sleep continued to dream. The two are related but not identical — dreaming has its own neural address, separate from the sleep stage that was thought to produce it.
Where Dreams Stop
Damage to the temporo-parietal junction and the medial prefrontal cortex reliably caused dreaming to cease — without disturbing sleep itself. These regions, not the brain stem, are where dreaming actually lives.
The Forebrain Generates Dreams
Solms identified forebrain mechanisms — particularly dopamine pathways associated with motivation and desire — as the true engines of dream production. This is the part of the brain that wants things.
Dreaming Is Purposive
The regions involved are those that handle emotion, memory, motivation, and self-referential thought — exactly the functions that depth psychology has always placed at the center of why dreams occur.
What This Means for Jung
Jung spent his career arguing that the unconscious was not a passive storage room for repressed material but an active, purposive layer of the psyche — one that generates imagery, symbols, and narratives with the goal of communicating something the conscious mind needs to hear. Dreams were its primary language.
The neuroscience establishment of his era had no way to confirm or deny this. The tools didn't exist. What Solms' research provided, decades later, was a map — a physical location for the processes Jung had been describing in psychological terms.
Where Jung and Solms Converge
Jung described dreams as arising from below conscious awareness and carrying emotional and symbolic content that the waking mind has not yet processed. Solms found that the brain regions responsible for dreaming are precisely those governing emotion, self-referential thought, and motivation — the unconscious machinery of wanting, fearing, remembering, and meaning-making.
Jung called the unconscious purposive — it moves toward something. Solms found that the dopamine-driven motivational systems of the forebrain are central to dream generation. The brain that dreams is the brain that desires. That is not a coincidence. That is the same thing described from two different directions.
Jung argued that the dream compensates — it brings forward what the conscious attitude has ignored or suppressed. Solms' data shows that dreaming involves regions associated with emotional memory and internal narrative, not the rational executive functions of the frontal cortex. The dreaming brain is not reasoning. It is feeling its way toward something.
The Man Behind the Research
Solms didn't arrive at this work as a disinterested technician. He trained as a psychoanalyst at the Institute of Psychoanalysis in London while simultaneously working in neurosurgery at the Royal London Hospital — two worlds that rarely share a corridor. He went on to found the field of neuropsychoanalysis, the formal attempt to build a bridge between brain science and depth psychology, and was reportedly the first person to use that term.
He is Professor of Neuropsychology at the University of Cape Town, Director of the Arnold Pfeffer Center for Neuropsychoanalysis at the New York Psychoanalytic Society, and Chair of the Research Committee of the International Psychoanalytical Association. His later book, The Hidden Spring, extends this work into a broader theory of consciousness — arguing that feeling, not thinking, is the primary function of consciousness and that it originates in the brain stem, not the cortex. This is a radical claim with deep resonance for anyone who has spent time working with dreams.
Why This Book Belongs on Your Reading List
This is not a light read. Solms writes for an academic and clinical audience, and the clinico-anatomical method he employs — mapping specific cognitive changes to specific brain lesions — requires patience and engagement. But for anyone who takes dreams seriously, what this book offers is something rare: hard evidence that the territory Jungian psychology has always worked in is real territory. The unconscious is not a metaphor. It has a location. It has mechanisms. And those mechanisms are doing exactly what Jung said they were doing — working on you while you sleep, in the language of image and emotion, toward something your waking mind hasn't finished with yet.
The science caught up. It just took a few decades.