Auto-immune diseases are characterized by an inappropriate inflammatory response against tissues in the body and represent a major health care burden. Pro-inflammatory cytokines such as TNF-α, IL-6 and IL-1β play a central role in the pathophysiology of many auto-immune diseases. Innovative therapies aimed at limiting pro-inflammatory cytokine production in a more physiological manner are warranted. In previous research conducted in an individual known as "the iceman", the investigators found that, through a autodidact concentration/meditation technique, he appears to mount a controlled stress response, characterized by activation of the sympathetic nervous system and enhanced production of cortisol, both of which are known to result in immunosuppression. In accordance, while practicing this concentration/meditation technique, the inflammatory response during human endotoxemia (lipopolysaccharide [LPS] administration) was remarkably low in this individual. Therefore, this technique could provide a novel means of controlling the inflammatory response. However, the aforementioned results were obtained in just one subject, and hence can not serve as scientific evidence for the effectiveness of the concentration/meditation technique. The iceman claims that he can teach this technique to other subjects within a relatively short time frame. Therefore, in the present study the investigators wish to investigate the effect of concentration/meditation on autonomic nervous system activity and the inflammatory response during experimental human endotoxemia in a controlled manner, by comparing a group of subjects that are trained by "the iceman" and practice the concentration/meditation technique with a group of subjects which do not.

Inclusion Criteria:

• Age ≥18 and ≤35 yrs
• Male
• Healthy
• Travel insurance (for travel to Poland for the training in the concentration/meditation technique)

Exclusion Criteria:

• Use of any medication
• Smoking
• Use of recreational drugs within 21 days prior to endotoxemia experiment day
• Use of caffeine or alcohol within 1 day prior to endotoxemia experiment day
• Previous participation in a trial where LPS was administered
• Surgery or trauma with significant blood loss or blood donation within 3 months prior to endotoxemia experiment day
• Participation in another clinical trial within 3 months prior to endotoxemia experiment day.
• History, signs, or symptoms of cardiovascular disease
• History of frequent vaso-vagal collapse or of orthostatic hypotension
• History of atrial or ventricular arrhythmia
• Hypertension (RR systolic >160 or RR diastolic >90)
• Hypotension (RR systolic <100 or RR diastolic <50)
• Conduction abnormalities on the ECG consisting of a 1st degree atrioventricular block or a complex bundle branch block
• Renal impairment: plasma creatinine >120 µmol/L
• Liver function abnormality: alkaline phosphatase>230 U/L and/or ALT>90 U/L
• History of asthma
• Obvious disease associated with immune deficiency.
• CRP > 20 mg/L, WBC > 12x109/L, or clinically significant acute illness, including infections, within 4 weeks before endotoxemia day