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Objective In migraine, there is an altered behavior of patients during the attack and an altered connectivity in the cortical structures modulating and encoding the sensation and pain. Thus, we hypothesized that the extent of the peripersonal space (PPS) and the responses in the PPS may change during a migraine attack. For this reason, we analyzed the modulation of somatosensory blink reflex (SBR) in the PPS during episodic migraine. Design Cross-sectional assessment of modulation of SBR in patients with migraine. Setting Headache outpatient clinic of a tertiary referral center. Subjects We included 22 patients with episodic migraine, of whom 13 individuals were in the interictal period and nine were experiencing a headache episode. We also included 14 healthy individuals. The three groups were similar in age and gender. Methods SBR was recorded when the participants were sitting with their forearm in the extrapersonal space and also when their hands were in the PPS surrounding the face. Latency, amplitude, and area under the curve (AUC) were measured and compared. Results The amplitude and AUC of the SBR were significantly higher in patients during the attack compared with healthy subjects. The magnitude of the SBR was increased in the PPS in healthy subjects, whereas the increase was not significant in patients during the attack or in the interictal period. Conclusions We think that the modulation in the PPS is defective in patients with migraine both during the acute attack and in the interictal phase, suggesting diminished top-down modulation of the SBR. [ABSTRACT FROM AUTHOR]

• Patients with dry eye have an abnormal enhancement of excitability in blink reflex circuits. • The abnormalities were present in both, primary and secondary dry eye syndromes. • The abnormal sensorimotor integration may be due to sensitization due to excessive sensory input We hypothesized that there may be changes in sensory integration pathways in patients with dry eye. To confront this issue, we analyzed blink reflex (BR), prepulse modulation (PPM) of BR, and excitability recovery of BR to paired stimuli in 17 experimental subjects with dry eye syndrome. We included 17 experimental subjects, 8 with primary and 9 with secondary, dry eye syndrome. We also examined a control group of 14 age and gender matched control subjects. After clinical evaluation, we recorded BR, PPM of BR (at 50 and 100 ms intervals) and BR percentage recovery to paired stimulation (at 300 and 500 ms intervals). None of the patients had any spasm activity. Experimental subjects had significantly larger R2 and R2c AUCs, significantly greater excitability recovery at 300 ms interval and significantly reduced R2 and R2c prepulse inhibition, in comparison to control subjects. Experimental subjects with primary dry eye syndrome had higher number of spontaneous blinks than experimental subjects with secondary dry eye syndrome (54.0 ± 10.3 for primary dry eye and 43.5 ± 13.3 secondary dry eye). Our results are compatible with increased excitability and abnormalities in sensorimotor integration in blink reflex circuits of patients with dry eye. This suggests the development of adaptive changes in brainstem synaptic activity, aimed at facilitation of blinking in the context of increased sensory input from corneal irritation. [ABSTRACT FROM AUTHOR]