title: Attentional Control of Gait and Falls: Is Cholinergic Dysfunction a Common Substrate in the Elderly and Parkinson's Disease?
abstract: The aim of this study was to address whether deficits in the central cholinergic activity may contribute to the increased difficulty to allocate attention during gait in the elderly with heightened risk of falls. We recruited 50 participants with a history of two or more falls (33 patients with Parkinson's Disease and 17 older adults) and 14 non-fallers age-matched adults. Cholinergic activity was estimated by means of short latency afferent inhibition (SAI), a transcranial magnetic stimulation (TMS) technique that assesses an inhibitory circuit in the sensorimotor cortex and is regarded as a global marker of cholinergic function in the brain. Increased difficulty to allocate attention during gait was evaluated by measuring gait performance under single and dual-task conditions. Global cognition was also assessed. Results showed that SAI was reduced in patients with PD than in the older adults (fallers and non-fallers) and in older adults fallers with respect to non-fallers. Reduction in SAI indicates less inhibition i.e., less cholinergic activity. Gait speed was reduced in the dual task gait compared to normal gait only in our faller population and changes in gait speed under dual task significantly correlated with the mean value of SAI. This association remained significant after adjusting for cognitive status. These findings suggest that central cholinergic activity may be a predictor of change in gait characteristics under dual tasking in older adults and PD fallers independently of cognitive status.
authors.affiliation: Department of Neuroscience, Rehabilitation, Ophthalmology, Genetics and Maternal Child Health, University of Genoa Genoa, Italy.
authors.forename: Elisa
authors.initials: E
authors.lastname: Pelosin
authors.affiliation: Department of Neuroscience, Rehabilitation, Ophthalmology, Genetics and Maternal Child Health, University of Genoa Genoa, Italy.
authors.forename: Carla
authors.initials: C
authors.lastname: Ogliastro
authors.affiliation: Department of Neuroscience, Rehabilitation, Ophthalmology, Genetics and Maternal Child Health, University of Genoa Genoa, Italy.
authors.forename: Giovanna
authors.initials: G
authors.lastname: Lagravinese
authors.affiliation: Department of Experimental Medicine, Section of Human Physiology and Centro Polifunzionale di Scienze Motorie, University of Genoa Genoa, Italy.
authors.forename: Gaia
authors.initials: G
authors.lastname: Bonassi
authors.affiliation: Center for the Study of Movement, Cognition and Mobility, Department of Neurology, Tel Aviv Sourasky Medical CenterTel Aviv, Israel; Department of Physical Therapy, Sackler Faculty of Medicine and Sagol School of Neuroscience, Tel Aviv UniversityTel Aviv, Israel.
authors.forename: Anat
authors.initials: A
authors.lastname: Mirelman
authors.affiliation: Center for the Study of Movement, Cognition and Mobility, Department of Neurology, Tel Aviv Sourasky Medical CenterTel Aviv, Israel; Department of Physical Therapy, Sackler Faculty of Medicine and Sagol School of Neuroscience, Tel Aviv UniversityTel Aviv, Israel.
authors.forename: Jeffrey M
authors.initials: JM
authors.lastname: Hausdorff
authors.affiliation: Department of Neuroscience, Rehabilitation, Ophthalmology, Genetics and Maternal Child Health, University of Genoa Genoa, Italy.
authors.forename: Giovanni
authors.initials: G
authors.lastname: Abbruzzese
authors.affiliation: Department of Experimental Medicine, Section of Human Physiology and Centro Polifunzionale di Scienze Motorie, University of Genoa Genoa, Italy.
authors.forename: Laura
authors.initials: L
authors.lastname: Avanzino
keywords: Parkinson’s disease; attention; cholinergic system; dual task gait; falls; transcranial magnetic stimulation (TMS)