title: The serendipity case of the pedunculopontine nucleus low-frequency brain stimulation: chasing a gait response, finding sleep, and cognition improvement.
abstract: Deep brain stimulation (DBS) of the subthalamic nucleus (STN) is an efficacious therapy for Parkinson's disease (PD) but its effects on non-motor facets may be detrimental. The low-frequency stimulation (LFS) of the pedunculopontine nucleus (PPN or the nucleus tegmenti pedunculopontini - PPTg-) opened new perspectives. In our hands, PPTg-LFS revealed a modest influence on gait but increased sleep quality and degree of attentiveness. At odds with potential adverse events following STN-DBS, executive functions, under PPTg-ON, ameliorated. A recent study comparing both targets found that only PPTg-LFS improved night-time sleep and daytime sleepiness. Chances are that different neurosurgical groups influence either the PPN sub-portion identified as pars dissipata (more interconnected with GPi/STN) or the caudal PPN region known as pars compacta, preferentially targeting intralaminar and associative nucleus of the thalamus. Yet, the wide electrical field delivered affects a plethora of en passant circuits, and a fine distinction on the specific pathways involved is elusive. This review explores our angle of vision, by which PPTg-LFS activates cholinergic and glutamatergic ascending fibers, influencing non-motor behaviors.
authors.affiliation: Department of Neuroscience, "Tor Vergata" University , Rome , Italy ; IRCCS, Fondazione Santa Lucia , Rome , Italy.
authors.forename: Alessandro
authors.initials: A
authors.lastname: Stefani
authors.forename: Antonella
authors.initials: A
authors.lastname: Peppe
authors.forename: Salvatore
authors.initials: S
authors.lastname: Galati
authors.forename: Mario Stampanoni
authors.initials: MS
authors.lastname: Bassi
authors.forename: Vincenza
authors.initials: V
authors.lastname: D'Angelo
authors.forename: Mariangela
authors.initials: M
authors.lastname: Pierantozzi
keywords: Parkinson disease; deep brain stimulation; executive function; neuromodulation; sleep structure