Prepulse modulation and recovery of trigemino-cervical reflex in normal subjects
- 35 Downloads
In this study, we analyzed the inhibitory control on the trigemino-cervical reflex (TCR), and whether or not prepulse modulation (PPM) has an effect on TCR. Thus, we studied the PPM of TCR. We hypothesized that TCR would presumably be under the modulatory effect after the prepulse stimulus similar to blink reflex (BR). We also studied the recovery of TCR which was previously shown.
We included 13 healthy individuals. All subjects underwent recordings of TCR, TCR-PPM, and recovery of TCR. For TCR-PPM, a subthreshold stimulus to second finger 50 or 100 ms before the test stimulus was applied. For recovery of TCR, two stimuli at the infraorbital nerve were applied at 300, 500, and 800 ms interstimulus intervals (ISIs).
There was an inhibition of bilateral late responses of TCR at the ISIs of both 50 ms and 100 ms. There was no change of latencies. Full recovery of TCR did not develop even at the ISI 800 ms.
We have provided an evidence for the TCR-PPM in healthy subjects for the first time in this study. The prepulse inhibition is attributed to the functions of the pedunculopontine tegmental nucleus. Our study provides a strong indication that there are connections between pedunculopontine tegmental nucleus and trigemino-cervical circuit, which produces TCR.
KeywordsPrepulse modulation (PPM) Trigemino-cervical reflex (TCR) Prepulse inhibition (PPI) Recovery Pedunculopontine tegmental nucleus
The authors thank Zeynep Değirmenci, Sibel Kilinc, Vildan Altop, Mecit Sepetcioglu, and Esat Cetinkaya for excellent technical assistance.
Compliance with ethical standards
The study was approved by the institutional review board, and informed consent was obtained.
Conflict of interest
The authors declare that they have no conflict of interest.
- 11.Serrao M, Cortese F, Andersen OK, Conte C, Spaich EG, Fragiotta G, Ranavolo A, Coppola G, Perrotta A, Pierelli F (2015) Modular organization of the head retraction responses elicited by electrical painful stimulation of the facial skin in humans. Clin Neurophysiol 126:2306–2313CrossRefGoogle Scholar
- 20.Serrao M, Di Fabio R, Bartolo M, Perrotta A, Tassorelli C, Coppola G, Davassi C, Padua L, Sandrini G, Pierelli F (2011) The contribution of trigemino-cervical reflexes in distinguishing progressive supranuclear palsy from multiple system atrophy. Clin Neurophysiol 122:1812–1815CrossRefGoogle Scholar