Professor Emeritus Dr. Dr. Burkhard Bromm celebrated his 80th birthday on June 30, 2015. He studied physics, mathematics, and medicine in Tübingen, Hamburg, Kiel, and Stockholm. He received his habilitation in physiology from the University of Kiel, accepted a professorship at Ruhr University Bochum, and in 1974 became Director of the Department of Neurophysiology at the University of Hamburg. From 1977 to 2000, he served as Managing Director of the Institute of Physiology at the University Medical Center Hamburg-Eppendorf. His research focused on the analysis of central nervous system pain mechanisms and the neuronal correlates of pain. His electrophysiological analyses provided groundbreaking new insights into the information processing of pain and the neurological basis of the awareness of pain-related brain activity.

On the occasion of his 80th birthday, a celebratory symposium of the Hamburg Academy of Sciences was held on July 3, 2015, in honor of the honoree, on the topic of

Pain and consciousness

The symposium, from today's perspective, aimed to explore the fact that patients can modulate pain psychologically and mentally. The focus was on neurophysiological mechanisms by which therapeutic methods, such as cognitive hypnotherapy (hypnotic induction, relaxation, dissociation, analgesia, safe space, distraction, pain reframing), autosuggestion, placebo, or nocebo, can influence pain. The active, volitionally controlled alteration of pain perception was also to be addressed. The symposium thus led to the boundaries of the "mind-body problem." The honoree wanted to highlight this central theme of human existence on the occasion of the symposium. Prof. Dr. Dr. Bromm explained: "At 80, one is allowed to do that, if at all. If not now, when?".

Following a welcome address by the Dean of the Faculty of Medicine at the University Medical Center Hamburg, Prof. Dr. Dr. Uwe Koch-Gromus, greetings were offered by Prof. Dr. Jürgen Schwarz, Center for Molecular Neurobiology Hamburg, Prof. Dr. Heimo Ehmke, Institute for Molecular and Integrative Physiology, University Medical Center Hamburg, Prof. Dr. Wolfgang Jelkmann, President of the German Physiological Society, Prof. Dr. Rolf-Detlef Treede, President of the International Association for the Study of Pain, and Prof. Dr. Ing. Prof. EH Edwin J. Kreuzer, President of the Academy of Sciences in Hamburg.

The subsequent symposium was moderated by Prof. Dr. Jörn Hennig Wolf, spokesperson of the Academy of Sciences in Hamburg – working group “Rational decisions on uncertain foundations”.

Professor Dr. Hartmut Göbel, from the Kiel Pain Clinic, introduced the clinical significance of both voluntary and involuntary effects of cognitive and affective influences on pain. Using clinical examples and scientific findings, he illustrated the central importance of the evaluative, affective, and cognitive components of the pain experience. Modern pain therapy is based on replacing the earlier linear-causal model of pain. Physiological, biochemical, behavioral, and subjective cognitive mechanisms, including systems-theoretical processing, determine the conscious experience of pain and must be the focus of practical therapy. Only in this way can the initiation, maintenance, and chronification of pain be understood and effectively treated.

Dr. Falk Eippert, University of Oxford, presented experimental studies on the effects of placebos during nociceptive stimulation with laser stimuli. He further supported these findings with brain imaging experiments. His results bridged the gap between clinical observations and neurophysiological research. Falk Eippert and his colleagues used functional magnetic resonance imaging (fMRI) to observe the spinal cord of subjects while they participated in a painful experiment. Among other findings, the researchers discovered that even the nerve cells of the spinal cord reacted less actively to the same intensity of heat pain when the subject expected pain relief after receiving a placebo.

Professor Dr. Rolf-Detlef Treede, Chair of Neurophysiology at Heidelberg University and President of the International Association for the Study of Pain, explained the significance of EEG and MEG signals for conscious processes in pain. He presented new findings on cognitive potentials, which are reduced under anesthesia and enhanced by attentional efforts or distractions. He explained in detail the brain structures responsible for this and discussed neurophysiological correlates of pain and itching.

Professor Dr. Dr. Gerhard Roth, Institute for Brain Research at the University of Bremen, President of the German National Academic Foundation from 2003 to 2011, discussed findings on the neurophysiology of consciousness and free will, as well as conscious and intentional decisions. He explained the structures and functions of the limbic system and the neural basis of affects and emotions. The unconscious largely determines consciousness; it develops ontogenetically before consciousness and establishes the basic structures of how we interact with ourselves and our environment very early on. Emotional experiential memory has the first and last word in the formation of our desires and intentions, and in the final decision regarding their realization.

In his lecture entitled "On the Freedom to Suppress One's Pain," the honoree himself addressed the possibilities of free will in altering pain. Pain, he explained, can distract attention from all other experiences. Building on clinical and experimental findings, he elaborated on how the course of pain sensations can be modified and which neuronal mechanisms underlie this process. Numerous findings have now demonstrated that the physically measurable neurological processes required for a conscious and deliberate action have already begun long before the individual experiencing the pain perceives a conscious decision. The concept of free will, therefore, also becomes a product of neurological processes that have already taken place long before the action itself is consciously perceived and carried out.

The explanations led to the limits of human consciousness and the foundations of the individual's personal responsibility for feelings, freedom, and will.

The symposium concluded with a celebratory evening on the Rickmer Rickmers.

The following video shows the remarks of brain researcher Prof. Dr. Dr. Bromm on free will on the occasion of a previous lecture at the Hermann-Ehlers-Academy in Kiel.