Perrotta A, et al. - Experts contemplated if the stimulation frequency, the pain phases and different diagnoses of trigeminal autonomic cephalalgias (TACs) could exert an impact on the habituation to pain. It was discovered that trigeminal autonomic cephalagias displayed a frequency-related defective habituation of nociceptive trigeminal responses at the higher stimulation frequencies, regardless of the diagnosis and/or the disease phase. Clinical similarities were brought to light in the different subtypes of TACs that were in parallel with a trait-dependent dysfunction in pain processing.