ABSTRACT
Increased, decreased or normal excitability to transcranial magnetic stimulation (TMS) has been reported in the motor (M1) and visual cortices of patients with migraine. Light deprivation (LD) has been reported to modulate M1 excitability in control subjects (CS). Still, effects of LD on M1 excitability compared to exposure to environmental light exposure (EL) had not been previously described in patients with migraine (MP). To further our knowledge about differences between CS and MP, regarding M1 excitability and effects of LD on M1 excitability, we opted for a novel approach by extending measurement conditions. We measured motor thresholds (MTs) to TMS, short-interval intracortical inhibition, and ratios between motor-evoked potential amplitudes and supramaximal M responses in MP and CS on two different days, before and after LD or EL. Motor thresholds significantly increased in MP in LD and EL sessions, and remained stable in CS. There were no significant between-group differences in other measures of TMS. Short-term variation of MTs was greater in MP compared to CS. Fluctuation in excitability over hours or days in MP is an issue that, until now, has been relatively neglected. The results presented here will help to reconcile conflicting observations.
Subject(s)
Evoked Potentials, Motor/physiology , Migraine Disorders/physiopathology , Motor Cortex/physiopathology , Adult , Cross-Over Studies , Female , Humans , Photic Stimulation , Transcranial Magnetic StimulationABSTRACT
BACKGROUND: New daily persistent headache (NDPH) is a primary chronic daily headache that is generally considered to be difficult to treat. Migraine has been linked to comorbid psychiatric conditions, mainly mood and anxiety disorders, but NDPH has never been linked to psychiatric conditions, and never studied extensively for such an association. CASE: We report nine cases (six women and three men) of patients diagnosed with NDPH and panic disorder who were treated for both conditions. Six of them (66%) had good or excellent responses. CONCLUSION: The spectrum of anxiety disorders, particularly panic disorder, should be considered in NDPH patients. Simultaneous treatment of both disorders may lead to good outcomes.