In Memoriam: Jan Gybels

Jan Gybels, MD, PhD
Leuven, Belgium
May 29, 2011

On May 29, 2011, Jan Gybels, co-founder of the IASP and world authority in pain research and pain treatment, suddenly passed away at the age of 82. Jan died in the Lubéron in southern France, a region that was very dear to his heart, and where he often resided in his beautiful summerhouse. He will be missed deeply by his family, his many friends, colleagues and patients. Although having attained a respectable age, one thought that death would never get a grip on him. With his death, we lose one of the most "human" of professors, one of the most scientific of neurosurgeons, and a very dear friend.

Jan Gybels was born in 1928, in the city of Aarschot, not far from the university city of Leuven. His father was a highly respected physician, and it is likely that Jan inherited his interest in medicine and science from his father. In the course of basic medical training at the University of Leuven, Jan also made his first steps towards neurophysiological research. In 1955, he graduated in medicine with the dissertation "Electrophysiological study of autonomic and cerebral responses following somatic stimulation." Subsequently, he went to the Montréal Neurological Institute for training in neurosurgery, as a student of illustrious teachers such as Wilder Penfield, Herbert Jasper and Brenda Milner. He completed his PhD thesis in the laboratory of Herbert Jasper on single unit recordings in behaving monkeys in a model of Parkinson's disease. Following training in neurosurgery, Jan moved to Queen Square in London for further studies in neurology, before returning to Belgium in the early 1960s. After having worked for some years at the Born-Bunge Institute in Antwerp, he was appointed professor of Neurology and Neurosurgery at the Catholic University of Leuven, where he founded the Laboratory for Experimental Neurology. Jan's early interest was to investigate the role of the small unmyelinated C-fibers and the thinly myelinated A-delta fibers in pain perception. There he and his co-workers conducted pioneering studies of human microneurography, often recording from their own peripheral nerve fibers. This was science at its very best! In collaboration with Johan Van Hees, Hermann Handwerker and Hugo Adriaensen, the lab produced a series of seminal papers on the role of C-fibers and A-delta fibers in human pain perception (1, 2). These studies have become citation classics in the field and are mentioned in every textbook of pain physiology. Being aware of the need for animal models in order to get a better understanding of the mechanisms and the treatment of clinical pain conditions, Jan was also one of the first to develop and validate animal models of persistent pain. By this means he could test the feasibility of new targets for deep brain stimulation in the treatment of chronic pain. With respect to the pain clinic, non-ablative neurostimulation procedures were his treatment of choice. He was a world authority on surgical procedures such as peripheral nerve stimulation, dorsal column stimulation and deep brain stimulation. Despite his conviction in the efficacy of these techniques, he remained very critical about these procedures, and carefully selected potential patients. Towards the end of his career, he accepted the challenge to write a new textbook on the neurosurgical treatment of pain. His textbook, co-authored by William Sweet, remains the critical reference work par excellence in the field (3).

Jan Gybels is in first instance known for his seminal work in the field of pain. However, he also made major contributions in the fields of image-guided stereotactic interventions, and the neurosurgical treatment of Parkinson's disease and neuropsychiatric disorders. As early as the late 1960s, Jan had teamed up with computer scientists in order to develop an automated system for locating intracerebral brain targets for stereotactic neurosurgery (4). By the late 1970s, these efforts had resulted in new methods for fusing angiographic data of the brain with a stereotactic coordinate system. This innovation made him one of the pioneers of image-assisted brain neurosurgery.

Jan Gybels was always an inspiration to his students, one who embodied the ideal of a genuine, critical and inquisitive neuroscientist, full of novel ideas. As a supervisor, he granted great freedom of inquiry to his students, leaving them to develop their own creative solutions to problems. Nonetheless, his critical questions, comments and subtle hints were always greatly appreciated; after a discussion with him, one always felt oneself to be on the right track again. He imparted his caution and criticism with respect to new and highly publicized developments.

In 1994, Jan Gybels officially retired, and the University of Leuven bestowed on him the status of professor emeritus. For this occasion, a liber amicorum was published (5). This volume comprised responses of more than 30 scientists and neurosurgeons, world authorities in their field, who were asked to make an account of their personal experience with Jan, or to reflect upon his scientific achievements. Patrick Wall wrote the following:

"The first generation of neurosurgeons contained giants who performed mighty deeds. As is the way with giants, they were dominating patriarchs capable of great wonders and of gigantic blunders. The next generation moved into two directions. One group developed their art by concentrating on technique. The other, much smaller group, reacted with awe and thoughtful questions. Jan Gybels is one of the leaders of that small group and for that we owe him our deepest respect."

Jan's scientific life was balanced by his lifelong attachment to his wife and by his devotion to his four children. In the years following his retirement, Jan remained very active in scientific and clinical matters. So he became president of the Belgian Royal Academy of Medicine. More recently, Jan started devoting more and more time to his family, placing particular emphasis on the education of his many grandchildren, thereby retiring a bit from the public scene. However, he intrinsically remained interested in the research topics to which he had contributed so much, and which remained so dear to his heart: attaining a better understanding of the neurophysiological mechanisms underlying analgesic neurosurgical procedures and deep brain stimulation for neuropsychiatric interventions (6, 7).

Not only will we miss the scientist and the great neurosurgeon but also the person. Jan Gybels was a very refined person, a modern renaissance man. He had an insatiable interest in literature, painting, music, philosophy and performing arts. Jan was also a great lover of good food, and there were few things in life that he appreciated more than a nice dinner with fine wine in the company of family and good friends. Jan was a very sociable and friendly person with an incredible sense of humor; whether during breaks at scientific meetings or at parties, he would always be surrounded by a large crowd of people, all eager not to miss a single word of what he was saying. He also liked the company of young and as yet unknown scientists, who were overwhelmed by the fact that this famous professor showed a sincere interest in what they were doing. Despite his fame and renown, modesty, discretion and honesty always stayed his trademarks.

Our many wonderful memories of Jan will keep him alive in our minds, and will continue to guide us to make the right decisions in science and life in general, and to remain critical of heedless innovation, until a very high standard of proof has been met.

Ron Kupers, PhD

Selected Readings

  1. Gybels J, Handwerker HO, Van Hees J. A comparison between the discharges of human nociceptive nerve fibres and the subject's ratings of his sensations. J Physiol 1979;292:193-206.
  2. Adriaensen H, Gybels J, Handwerker HO, Van Hees J. Response properties of thin myelinated (A-delta) fibers in human skin nerves. J Neurophysiol 1983; 49: 111-122.
  3. Gybels J and Sweet WH. Neurosurgical treatment of persistent pain: physiological and pathological mechanisms of human pain. Karger, Basel, 1989.
  4. Peluso F, Gybels J. Computer calculation of two target trajectory with "centre of arc-target" stereotaxic equipment. Acta Neurochir (Wien). 1969;21:173-80.
  5. Kupers R, "A look into the seeds of time, Liber Amicorum Jan Gybels," Leuven University Press, 1994.
  6. Gybels J, et al., Neuromodulation of pain. Eur J Pain. 1998;2:203-209.
  7. Nuttin B, Cosyns P, Demeulemeester H, Gybels J, Meyerson B. Electrical stimulation in anterior limbs of internal capsules in patients with obsessive-compulsive disorder. Lancet 1999;354:1526.