The induction of nociceptive long-term potentiation (LTP) by high-frequency stimulation (HFS) is paralleled by modality-specific sensory changes at the conditioned site (increased sensitivity to noxious mechanical but not thermal stimuli; Lang et al. 2005 Abstr.: 11th World Congress on Pain, p61). Here we compared somatosensory changes at the conditioned and an adjacent site (ie. in areas of primary vs. secondary hyperalgesia). HFS induced a long-lasting increase of pain sensation to electrical test stimuli applied through the conditioning electrode (noci-ceptive LTP: +101%, p<0.001; n=24). Mechanical sensitivity (tactile detection, vibration, pain to pinprick and blunt pressure stimuli, and suprathreshold perception for pricking pain and pain summation) was tested at 1 hour before and after HFS. Significant alterations of sensitivity after HFS were found for tactile allodynia, hyperalgesia to pinprick and blunt pressure both in the area of primary and of secondary hyperalgesia. The occurrence of pinprick-hyperalgesia was highly correlated between the two sites (r=0.83). In conclusion, the induction of homosynaptic LTP in humans led to similar modality-specific changes in areas of primary and sec-ondary hyperalgesia suggesting a similar heterosynaptic facilit-ation of spinal nociceptive neurons as the common underlying mechanism. Supp. by DFG (Tr 236/16–1) & BMBF (01EM0506).