title: After Effects of Cerebellar Continuous Theta Burst Stimulation on Reflexive Saccades and Smooth Pursuit in Humans.
abstract: The use of cerebellar repetitive transcranial magnetic stimulation has been attempted for perturbing reflexive and voluntary eye movements, but discrepancies are seen between the results of distinct studies possibly due to the different stimulation sites, intensities, and paradigms. We describe the after effects of 20 and 40 s continuous Theta Burst Stimulation (cTBS) as compared to sham stimulation, applied over the lateral cerebellar vermis and paravermis on Reflexive Saccades (RS) and Smooth Pursuit (SP) eye movements, recorded in the 30 min following stimulation. The experiments were carried out in eight healthy volunteers, and eye movements were recorded monocularly with video-oculography. The 40 s cTBS significantly increased the amplitude of ipsilateral RS and the acceleration of the ipsilateral SP, and this effect was detectable all over the 30-min recording period; 40 s cTBS did not modify the other parameters, namely the peak velocity, the duration and the latency of RS, and the latency and the velocity of SP. The 20 s cTBS was ineffective on all RS and SP parameters. Finally, we detected a significant quite-linear reduction of RS peak velocity over time, but this was independent from cTBS and was probably caused by fatigue. The effects of 40 s cTBS in our experiments mimic the disorder of ocular motility in Wallenberg's syndrome and could result from functional impairment of cerebellopontine pathways. This effect lasts 30 min at least, and can provide a useful framework for adaptive ocular motor studies.
authors.affiliation: Department of Public Health, Experimental and Forensic Medicine, University of Pavia, Via Forlanini 2, 27100, Pavia, Italy. silvia.colnaghi@unipv.it.|Laboratory of Neuro-otology and Neuro-ophtalmology, C. Mondino National Neurological Institute, Pavia, Italy. silvia.colnaghi@unipv.it.
authors.forename: Silvia
authors.initials: S
authors.lastname: Colnaghi
authors.affiliation: Department of Electrical, Computer and Biomedical Engineering, University of Pavia, Pavia, Italy.
authors.forename: P
authors.initials: P
authors.lastname: Colagiorgio
authors.affiliation: Department of Electrical, Computer and Biomedical Engineering, University of Pavia, Pavia, Italy.
authors.forename: S
authors.initials: S
authors.lastname: Ramat
authors.affiliation: Department of Brain and Behavioral Sciences, University of Pavia, Pavia, Italy.|Brain Connectivity Center, C. Mondino National Neurological Institute, Pavia, Italy.
authors.forename: E
authors.initials: E
authors.lastname: D'Angelo
authors.affiliation: Non-invasive Brain Stimulation Unit, Santa Lucia Foundation IRCCS, Rome, Italy.|University of Rome Tor Vergata, Rome, Italy.
authors.forename: G
authors.initials: G
authors.lastname: Koch
authors.affiliation: Laboratory of Neuro-otology and Neuro-ophtalmology, C. Mondino National Neurological Institute, Pavia, Italy.|Department of Brain and Behavioral Sciences, University of Pavia, Pavia, Italy.
authors.forename: M
authors.initials: M
authors.lastname: Versino
mesh_terms: D002531:Cerebellum / Q000502:physiology*; D053483:Eye Movement Measurements; D005260:Female; D006801:Humans; D008297:Male; D011698:Pursuit, Smooth / Q000502:physiology*; D012438:Saccades / Q000502:physiology*; D013997:Time Factors; D050781:Transcranial Magnetic Stimulation / Q000379:methods; D014741:Video Recording; D055815:Young Adult
keywords: Cerebellum; Saccades; Smooth pursuit; cTBS