Physiological Aging Impacts the Hemispheric Balances of Resting State Primary Somatosensory Activities
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To hone knowledge of sensorimotor cerebral organization changes with physiological aging, we focused on the primary somatosensory cortical area (S1). S1 neuronal pools (FS_S1) were identified by the functional source separation (FSS) algorithm applied to magnetoencephalographic recordings during median nerve stimulation. Age-dependence of FS_S1 was then studied at rest separately in the left and right hemispheres of 26 healthy, right-handed subjects between the ages of 24 and 95 years. The resting state FS_S1 spectral features changed with increasing age: (1) alpha activity slowed down; (2) total power increased only in the right hemisphere; (3) right>left interhemispheric asymmetry increased in the whole spectrum; (4) spectral entropy increased with age selectively in the left hemisphere. The present FSS-enriched electrophysiological procedure provided measures of resting state hand representation area sensitive to changes with age. Alterations were stronger in the right hemisphere. Relationships between resting state S1 activity and its responsiveness to external stimuli, revealed that the interhemispheric unbalances which emerged with age were conceivably due to an increased excitability within the right thalamocortical circuit impacting left versus right unbalances of spontaneous firing rates and of local inhibitory-excitatory networks.
KeywordsMagnetoencephalography (MEG) Interhemispheric asymmetries Median nerve stimulation Functional source separation (FSS)
The Authors thank Dr. Patrizio Pasqualetti for his support to statistical analysis. This study was supported by the following grants: (1) FISM—Fondazione Italiana Sclerosi Multipla—FaMuSNe Cod.2010/R/38; (2) FISM FaReMuS DiC diT Cod.2011/R/32; (3) Italian Ministry of Health Cod. GR-2008-1138642 ‘Promoting recovery from Stroke: Individually enriched therapeutic intervention in Acute phase’ [ProSIA]; (4) Royal Society International Joint Project—2010/R1: ‘The Key Movement Controllers: an EEG/fMRI study of the hand network dynamics [KeyMoCo]’.
- Allison T, Goff WR, Williamson PD, Vangilder G (1980) On the neural origin of the early components of the human somatosensory evoked potentials. In: Desmedt JE (ed) Progress in clinical neurophysiology. Karger, Basel, pp 51–68Google Scholar
- Assenza G, Zappasodi F, Squitti R, Altamura C, Ventriglia M, Ercolani M, Quattrocchi CC, Lupoi D, Passarelli F, Vernieri F, Rossini PM, Tecchio F (2009) Neuronal functionality assessed by magnetoencephalography is related to oxidative stress system in acute ischemic stroke. Neuroimage 44:1267–1273PubMedCrossRefGoogle Scholar
- Babiloni C, Binetti G, Cassarino A, Dal Forno G, Del Percio C, Ferreri F, Ferri R, Frisoni G, Galderisi S, Hirata K, Lanuzza B, Miniussi C, Mucci A, Nobili F, Rodriguez G, Luca Romani G, Rossini PM (2006) Sources of cortical rhythms in adults during physiological aging: a multicentric EEG study. Hum Brain Mapp 27:162–172PubMedCrossRefGoogle Scholar
- Crone NE, Miglioretti DL, Gordon B, Lesser RP (1998a) Functional mapping of human sensorimotor cortex with electrocorticographic spectral analysis. II. Event-related synchronization in the gamma band. Brain 121(Pt 12):2301–2315Google Scholar
- Crone NE, Miglioretti DL, Gordon B, Sieracki JM, Wilson MT, Uematsu S, Lesser RP (1998b) Functional mapping of human sensorimotor cortex with electrocorticographic spectral analysis. I. Alpha and beta event-related desynchronization. Brain 121(Pt 12):2271–2299Google Scholar
- Del Gratta C, Della Penna S, Ferretti A, Franciotti R, Pizzella V, Tartaro A, Torquati K, Bonomo L, Romani GL, Rossini PM (2002) Topographic organization of the human primary and secondary somatosensory cortices: comparison of fMRI and MEG findings. Neuroimage 17:1373–1383PubMedCrossRefGoogle Scholar
- Forss N, Mustanoja S, Roiha K, Kirveskari E, Makela JP, Salonen O, Tatlisumak T, Kaste M (2011) Activation in parietal operculum parallels motor recovery in stroke. Hum Brain Mapp 33:534–541Google Scholar
- Korvenoja A, Kirveskari E, Aronen HJ, Avikainen S, Brander A, Huttunen J, Ilmoniemi RJ, Jaaskelainen JE, Kovala T, Makela JP, Salli E, Seppa M (2006) Sensorimotor cortex localization: comparison of magnetoencephalography, functional MR imaging, and intraoperative cortical mapping. Radiology 241:213–222PubMedCrossRefGoogle Scholar
- Laufer Y, Elboim-Gabyzon M (2011) Does sensory transcutaneous electrical stimulation enhance motor recovery following a stroke? A systematic review. Neurorehabil Neural Repair 25(9): 799–809Google Scholar
- Stanley EM, Fadel JR, Mott DD (2011) Interneuron loss reduces dendritic inhibition and GABA release in hippocampus of aged rats. Neurobiol AgingGoogle Scholar
- Tecchio F, Assenza G, Zappasodi F, Mariani S, Salustri C, Squitti R (2011) Glutamate-mediated primary somatosensory cortex excitability correlated with circulating copper and ceruloplasmin. Int J Alzheimer’s Dis 2011:292593Google Scholar