• Attention;
  • Somatosensory association cortex;
  • Medial prefrontal cortex;
  • Involuntary orienting;
  • Threat detection


Negative potentials evoked by painful electrical stimulation of the sural nerve that occur at 100–180 ms poststimulus over the contralateral temporal scalp (CTN100-180) and at 130–200 ms over the fronto-central scalp (FCN130-200) exhibit unusual attention effects. That is, their amplitudes are larger when the painful evoking stimulus is unattended than when it is attended. In this experiment, I show that attention has no effect on the CTN100-180 evoked by a weak, nonthreatening sural nerve electrical stimulus. These data suggest that the generators of the CTN100-180, which include the somatosensory association areas in the parietal operculum, are specifically involved in detecting threatening somatosensory stimuli. The FCN130-200 showed a small increase in the unattended condition, which is consistent with the role of its medial prefrontal cortex generators in monitoring any situation that might require a change in attentional control.