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Turrini S, Wong B, Eldaief M, Press DZ, Sinclair DA, Koch G, Avenanti A, Santarnecchi E. The multifactorial nature of healthy brain ageing: Brain changes, functional decline and protective factors. Ageing Res Rev 2023; 88:101939. [PMID: 37116664 DOI: 10.1016/j.arr.2023.101939] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2022] [Revised: 04/14/2023] [Accepted: 04/24/2023] [Indexed: 04/30/2023]
Abstract
As the global population faces a progressive shift towards a higher median age, understanding the mechanisms underlying healthy brain ageing has become of paramount importance for the preservation of cognitive abilities. The first part of the present review aims to provide a comprehensive look at the anatomical changes the healthy brain endures with advanced age, while also summarizing up to date findings on modifiable risk factors to support a healthy ageing process. Subsequently, we describe the typical cognitive profile displayed by healthy older adults, conceptualizing the well-established age-related decline as an impairment of four main cognitive factors and relating them to their neural substrate previously described; different cognitive trajectories displayed by typical Alzheimer's Disease patients and successful agers with a high cognitive reserve are discussed. Finally, potential effective interventions and protective strategies to promote cognitive reserve and defer cognitive decline are reviewed and proposed.
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Affiliation(s)
- Sonia Turrini
- Precision Neuroscience & Neuromodulation Program, Gordon Center for Medical Imaging, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA; Centro studi e ricerche in Neuroscienze Cognitive, Dipartimento di Psicologia "Renzo Canestrari", Alma Mater Studiorum Università di Bologna, Campus di Cesena, Cesena, Italy
| | - Bonnie Wong
- Neuropsychology Program, Frontotemporal Disorders Unit, Massachusetts General Hospital, Harvard Medical School, Boston, MA , USA; Department of Psychiatry, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA
| | - Mark Eldaief
- Department of Psychiatry, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA; Department of Neurology, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA
| | - Daniel Z Press
- Department of Neurology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA, USA
| | - David A Sinclair
- Blavatnik Institute, Department of Genetics, Paul F. Glenn Center for Biology of ageing Research, Harvard Medical School, Boston, MA, USA
| | - Giacomo Koch
- Stroke Unit, Department of Systems Medicine, University of Tor Vergata, Rome, Italy; Department of Clinical and Behavioural Neurology, Santa Lucia Foundation IRCCS, Rome, Italy
| | - Alessio Avenanti
- Centro studi e ricerche in Neuroscienze Cognitive, Dipartimento di Psicologia "Renzo Canestrari", Alma Mater Studiorum Università di Bologna, Campus di Cesena, Cesena, Italy; Centro de Investigación en Neuropsicología y Neurociencias Cognitivas, Universidad Católica del Maule, Talca, Chile
| | - Emiliano Santarnecchi
- Precision Neuroscience & Neuromodulation Program, Gordon Center for Medical Imaging, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA.
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Yoo WK, Vernet M, Kim JH, Brem AK, Bashir S, Ifert-Miller F, Im CH, Eldaief M, Pascual-Leone A. Corrigendum: Interhemispheric and Intrahemispheric Connectivity From the Left Pars Opercularis Within the Language Network Is Modulated by Transcranial Stimulation in Healthy Subjects. Front Hum Neurosci 2020; 14:249. [PMID: 32760262 PMCID: PMC7372921 DOI: 10.3389/fnhum.2020.00249] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2020] [Accepted: 06/03/2020] [Indexed: 11/23/2022] Open
Affiliation(s)
- Woo-Kyoung Yoo
- Department of Physical Medicine and Rehabilitation, Hallym University Sacred Heart Hospital, Anyang, South Korea
| | - Marine Vernet
- Department of Neurology, Harvard Medical School, Boston, MA, United States.,ImpAct Team, Lyon Neuroscience Research Center (CRNL), CNRS UMR5292, INSERM, U1028, University Lyon 1, Bron, France
| | - Jung-Hoon Kim
- Weldon School of Biomedical Engineering, Purdue University, West Lafayette, IN, United States.,Department of Biomedical Engineering, Hanyang University, Seoul, South Korea
| | - Anna-Katharine Brem
- Department of Neurology, Harvard Medical School, Boston, MA, United States.,University Hospital of Old Age Psychiatry, University of Bern, Bern, Switzerland.,Department of Neuropsychology, Memory Clinic Zentralschweiz, Lucerne Psychiatry, Lucerne, Switzerland
| | - Shahid Bashir
- Department of Neurology, Harvard Medical School, Boston, MA, United States.,Department of Neurophysiology, Neuroscience Center, King Fahad Specialist Hospital, Dammam, Saudi Arabia
| | - Fritz Ifert-Miller
- Department of Neurology, Harvard Medical School, Boston, MA, United States
| | - Chang-Hwan Im
- Department of Biomedical Engineering, Hanyang University, Seoul, South Korea
| | - Mark Eldaief
- Department of Neurology, Harvard Medical School, Boston, MA, United States
| | - Alvaro Pascual-Leone
- Department of Neurology, Harvard Medical School, Boston, MA, United States.,Hinda and Arthur Institute for Aging Research and Center for Memory Health, Hebrew SeniorLife, Boston, MA, United States.,Guttmann Brain Health Institute, Institut Guttmann de Neurorehabilitation, Universitat Autonoma, Barcelona, Spain
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Hurtado-Puerto AM, Nestor K, Eldaief M, Camprodon JA. Safety Considerations for Cerebellar Theta Burst Stimulation. Clin Ther 2020; 42:1169-1190.e1. [PMID: 32674957 DOI: 10.1016/j.clinthera.2020.06.001] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2019] [Revised: 06/03/2020] [Accepted: 06/04/2020] [Indexed: 01/01/2023]
Abstract
PURPOSE The cerebellum is an intricate neural structure that orchestrates various cognitive and behavioral functions. In recent years, there has been an increasing interest in neuromodulation of the cerebellum with transcranial magnetic stimulation (TMS) for therapeutic and basic science applications. Theta burst stimulation (TBS) is an efficient and powerful TMS protocol that is able to induce longer-lasting effects with shorter stimulation times compared with traditional TMS. Parameters for cerebellar TBS are traditionally framed in the bounds of TBS to the cerebral cortex, even when the 2 have distinct histologic, anatomical, and functional characteristics. Tolerability limits have not been systematically explored in the literature for this specific application. Therefore, we aimed to determine the stimulation parameters that have been used for cerebellar. TBS to date and evaluate adverse events and adverse effects related to stimulation parameters. METHODS We used PubMed to perform a critical review of the literature based on a systematic review of original research studies published between September 2008 and November 2019 that reported on cerebellar TBS. We recovered information from these publications and communication with authors about the stimulation parameters used and the occurrence of adverse events. FINDINGS We identified 61 research articles on interventions of TBS to the cerebellum. These articles described 3176 active sessions of cerebellar TBS in 1203 individuals, including healthy participants and patients with various neurologic conditions, including brain injuries. Some studies used substantial doses (eg, pulse intensity and number of pulses) in short periods. No serious adverse events were reported. The specific number of patients who experienced adverse events was established for 48 studies. The risk of an adverse event in this population (n = 885) was 4.1%. Adverse events consisted mostly of discomfort attributable to involuntary muscle contractions. Authors used a variety of methods for calculating stimulation dosages, ranging from the long-established reference of electromyography of a hand muscle to techniques that atone for some of the differences between cerebrum and cerebellum. IMPLICATIONS No serious adverse events have been reported for cerebellar TBS. There is no substantial evidence of a tolerable maximal-efficacy stimulation dose in humans. There is no assurance of equivalence in the translation of cortical excitability and stimulation intensities from the cerebral cortex to cerebellar regions. Further research for the stimulation dose in cerebellar TBS is warranted, along with consistent report of adverse events. © 2020 Elsevier HS Journals, Inc.
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Affiliation(s)
- Aura M Hurtado-Puerto
- Laboratory of Neuropsychiatry and Neuromodulation, Massachusetts General Hospital, Boston, MA, USA; Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Charlestown, MA, USA; Centro de Estudios Cerebrales, Facultad de Ciencias, Universidad del Valle, Cali, Colombia.
| | - Kimberly Nestor
- Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Charlestown, MA, USA
| | - Mark Eldaief
- Laboratory of Neuropsychiatry and Neuromodulation, Massachusetts General Hospital, Boston, MA, USA; Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Charlestown, MA, USA
| | - Joan A Camprodon
- Laboratory of Neuropsychiatry and Neuromodulation, Massachusetts General Hospital, Boston, MA, USA; Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Charlestown, MA, USA
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Yoo WK, Vernet M, Kim JH, Brem AK, Bashir S, Ifert-Miller F, Im CH, Eldaief M, Pascual-Leone A. Interhemispheric and Intrahemispheric Connectivity From the Left Pars Opercularis Within the Language Network Is Modulated by Transcranial Stimulation in Healthy Subjects. Front Hum Neurosci 2020; 14:63. [PMID: 32256324 PMCID: PMC7090226 DOI: 10.3389/fnhum.2020.00063] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2019] [Accepted: 02/10/2020] [Indexed: 12/02/2022] Open
Abstract
Neural activity related to language can be modulated within widespread networks following learning or in response to disruption—including the experimental application of noninvasive brain stimulation. However, the spatiotemporal characteristics of such modulation remain insufficiently explored. The present study combined transcranial magnetic stimulation (TMS) and electroencephalography (EEG) to explore the modulation of activity across the language network following continuous theta-burst stimulation (cTBS) of the left pars opercularis. In 10 healthy subjects (21 ± 2 years old, four females), neuronavigated cTBS was delivered over the left pars opercularis of the frontal operculum (part of the traditional Broca’s area) at 80% of active motor threshold (AMT) stimulation intensity. Real cTBS and sham cTBS were performed in two different visits separated by at least 48 h. Before, immediately, and 10 min after cTBS, 30 single pulses of TMS were delivered to the left pars opercularis at 80% of the resting motor threshold (RMT), whereas EEG was simultaneously recorded. We examined the cTBS-induced modulation of phase locking values (PLVs) between the TMS-evoked potentials (TEPs) recorded over the pars opercularis and those recorded over its right-hemispheric homolog area, the left supramarginal area, and the left superior temporal area in different EEG frequency bands and different time windows following cTBS. cTBS to the left pars opercularis induced within the gamma band: (1) a significant increase in TEP phase synchronization between the left and right pars opercularis at an early time window (250–350 ms) following cTBS; and (2) significantly increased PLV with the left supramarginal area and the left superior temporal area at a later time window (600–700 ms). In the theta and delta band, cTBS to the left pars opercularis induced significantly increased phase synchronization of TEPs between the left pars opercularis and the posterior left hemispheric language areas at a late time window. In sham condition, there was a significant decrease in TEP phase synchronization of the high beta band between left pars opercularis and left superior temporal area at 200–300 ms. These results contribute to characterize the dynamics of the language network and may have implications in the development of noninvasive stimulation protocols to promote the language rehabilitation in aphasia patients.
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Affiliation(s)
- Woo-Kyoung Yoo
- Department of Physical Medicine and Rehabilitation, Hallym University Sacred Heart Hospital, Anyang, South Korea
| | - Marine Vernet
- Department of Neurology, Harvard Medical School, Boston, MA, United States.,ImpAct Team, Lyon Neuroscience Research Center (CRNL), CNRS UMR5292, INSERM, U1028, University Lyon 1, Bron, France
| | - Jung-Hoon Kim
- Weldon School of Biomedical Engineering, Purdue University, West Lafayette, IN, United States.,Department of Biomedical Engineering, Hanyang University, Seoul, South Korea
| | - Anna-Katharine Brem
- Department of Neurology, Harvard Medical School, Boston, MA, United States.,University Hospital of Old Age Psychiatry, University of Bern, Bern, Switzerland.,Department of Neuropsychology, Memory Clinic Zentralschweiz, Lucerne Psychiatry, Lucerne, Switzerland
| | - Shahid Bashir
- Department of Neurology, Harvard Medical School, Boston, MA, United States.,Department of Neurophysiology, Neuroscience Center, King Fahad Specialist Hospital, Dammam, Saudi Arabia
| | - Fritz Ifert-Miller
- Department of Neurology, Harvard Medical School, Boston, MA, United States
| | - Chang-Hwan Im
- Department of Biomedical Engineering, Hanyang University, Seoul, South Korea
| | - Mark Eldaief
- Department of Neurology, Harvard Medical School, Boston, MA, United States
| | - Alvaro Pascual-Leone
- Department of Neurology, Harvard Medical School, Boston, MA, United States.,Hinda and Arthur Institute for Aging Research and Center for Memory Health, Hebrew SeniorLife, Boston, MA, United States.,Guttmann Brain Health Institute, Institut Guttmann de Neurorehabilitation, Universitat Autonoma, Barcelona, Spain
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Putcha D, Brickhouse M, Touroutoglou A, Collins JA, Quimby M, Wong B, Eldaief M, Schultz A, El Fakhri G, Johnson K, Dickerson BC, McGinnis SM. Visual cognition in non-amnestic Alzheimer's disease: Relations to tau, amyloid, and cortical atrophy. Neuroimage Clin 2019; 23:101889. [PMID: 31200149 PMCID: PMC6562373 DOI: 10.1016/j.nicl.2019.101889] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/12/2019] [Revised: 05/28/2019] [Accepted: 06/01/2019] [Indexed: 12/15/2022]
Abstract
Heterogeneity within the Alzheimer's disease (AD) syndromic spectrum is typically classified in a domain-specific manner (e.g., language vs. visual cognitive function). The central aim of this study was to investigate whether impairment in visual cognitive tasks thought to be subserved by posterior cortical dysfunction in non-amnestic AD presentations is associated with tau, amyloid, or neurodegeneration in those regions using 18F-AV-1451 and 11C-PiB positron emission tomography (PET) and magnetic resonance imaging (MRI). Sixteen amyloid-positive patients who met criteria for either Posterior Cortical Atrophy (PCA; n = 10) or logopenic variant Primary Progressive Aphasia (lvPPA; n = 6) were studied. All participants underwent a structured clinical assessment, neuropsychological battery, structural MRI, amyloid PET, and tau PET. The neuropsychological battery included two visual cognitive tests: VOSP Number Location and Benton Facial Recognition. Surface-based whole-cortical general linear models were used to first explore the similarities and differences between these biomarkers in the two patient groups, and then to assess their regional associations with visual cognitive test performance. The results show that these two variants of AD have both dissociable and overlapping areas of tau and atrophy, but amyloid is distributed with a stereotyped localization in both variants. Performance on both visual cognitive tests were associated with tau and atrophy in the right lateral and medial occipital association cortex, superior parietal cortex, and posterior ventral occipitotemporal cortex. No cortical associations were observed with amyloid PET. We further demonstrate that cortical atrophy has a partially mediating effect on the association between tau pathology and visual cognitive task performance. Our findings show that non-amnestic variants of AD have partially dissociable spatial patterns of tau and atrophy that localize as expected based on symptoms, but similar patterns of amyloid. Further, we demonstrate that impairments of visual cognitive dysfunction are strongly associated with tau in visual cortical regions and mediated in part by atrophy. The Visual-cognitive Impairment Rating (VIR) scale is designed to rate visual cognitive and functional impairment. Performance on two visual cognitive tasks was associated with tau and atrophy in posterior cortical regions. Cortical atrophy is a partial mediator of the association between tau pathology and visual cognitive task performance.
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Affiliation(s)
- Deepti Putcha
- Frontotemporal Disorders Unit, Massachusetts General Hospital and Harvard Medical School, Boston, MA, USA; Department of Psychiatry, Massachusetts General Hospital and Harvard Medical School, Boston, MA, USA.
| | - Michael Brickhouse
- Frontotemporal Disorders Unit, Massachusetts General Hospital and Harvard Medical School, Boston, MA, USA; Department of Neurology, Massachusetts General Hospital and Harvard Medical School, Boston, MA, USA
| | - Alexandra Touroutoglou
- Frontotemporal Disorders Unit, Massachusetts General Hospital and Harvard Medical School, Boston, MA, USA; Department of Neurology, Massachusetts General Hospital and Harvard Medical School, Boston, MA, USA
| | - Jessica A Collins
- Frontotemporal Disorders Unit, Massachusetts General Hospital and Harvard Medical School, Boston, MA, USA; Department of Neurology, Massachusetts General Hospital and Harvard Medical School, Boston, MA, USA
| | - Megan Quimby
- Frontotemporal Disorders Unit, Massachusetts General Hospital and Harvard Medical School, Boston, MA, USA; Department of Neurology, Massachusetts General Hospital and Harvard Medical School, Boston, MA, USA
| | - Bonnie Wong
- Frontotemporal Disorders Unit, Massachusetts General Hospital and Harvard Medical School, Boston, MA, USA; Department of Psychiatry, Massachusetts General Hospital and Harvard Medical School, Boston, MA, USA
| | - Mark Eldaief
- Frontotemporal Disorders Unit, Massachusetts General Hospital and Harvard Medical School, Boston, MA, USA; Department of Neurology, Massachusetts General Hospital and Harvard Medical School, Boston, MA, USA
| | - Aaron Schultz
- Alzheimer's Disease Research Center, Massachusetts General Hospital and Harvard Medical School, Boston, MA, USA; Department of Neurology, Massachusetts General Hospital and Harvard Medical School, Boston, MA, USA
| | - Georges El Fakhri
- Gordon Center for Medical Imaging, Massachusetts General Hospital and Harvard Medical School, Boston, MA, USA; Department of Radiology, Massachusetts General Hospital and Harvard Medical School, Boston, MA, USA
| | - Keith Johnson
- Alzheimer's Disease Research Center, Massachusetts General Hospital and Harvard Medical School, Boston, MA, USA; Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital and Harvard Medical School, Boston, MA, USA; Gordon Center for Medical Imaging, Massachusetts General Hospital and Harvard Medical School, Boston, MA, USA; Department of Radiology, Massachusetts General Hospital and Harvard Medical School, Boston, MA, USA
| | - Bradford C Dickerson
- Frontotemporal Disorders Unit, Massachusetts General Hospital and Harvard Medical School, Boston, MA, USA; Alzheimer's Disease Research Center, Massachusetts General Hospital and Harvard Medical School, Boston, MA, USA; Department of Neurology, Massachusetts General Hospital and Harvard Medical School, Boston, MA, USA; Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital and Harvard Medical School, Boston, MA, USA
| | - Scott M McGinnis
- Frontotemporal Disorders Unit, Massachusetts General Hospital and Harvard Medical School, Boston, MA, USA; Department of Neurology, Massachusetts General Hospital and Harvard Medical School, Boston, MA, USA
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Kay C, Leveroni C, Eldaief M, Sherman J. AGR-3Early-Onset Behavioral Variant Frontotemporal Dementia and its Impact on the Family Unit: A Case Study. Arch Clin Neuropsychol 2017. [DOI: 10.1093/arclin/acx074.3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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Oberman L, Eldaief M, Fecteau S, Ifert-Miller F, Tormos JM, Pascual-Leone A. Abnormal modulation of corticospinal excitability in adults with Asperger's syndrome. Eur J Neurosci 2012; 36:2782-8. [PMID: 22738084 DOI: 10.1111/j.1460-9568.2012.08172.x] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
Most candidate genes and genetic abnormalities linked to autism spectrum disorders (ASD) are thought to play a role in developmental and experience-dependent plasticity. As a possible index of plasticity, we assessed the modulation of motor corticospinal excitability in individuals with Asperger's syndrome (AS) using transcranial magnetic stimulation (TMS). We measured the modulatory effects of theta-burst stimulation (TBS) on motor evoked potentials (MEPs) induced by single-pulse TMS in individuals with AS as compared with age-, gender- and IQ-matched neurotypical controls. The effect of TBS lasted significantly longer in the AS group. The duration of the TBS-induced modulation alone enabled the reliable classification of a second study cohort of subjects as AS or neurotypical. The alteration in the modulation of corticospinal excitability in AS is thought to reflect aberrant mechanisms of plasticity, and might provide a valuable future diagnostic biomarker for the disease and ultimately offer a target for novel therapeutic interventions.
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Affiliation(s)
- Lindsay Oberman
- Berenson-Allen Center for Noninvasive Brain Stimulation, Department of Neurology, Beth Israel Deaconess Medical Center and Harvard Medical School, Boston, MA, USA
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Pascual-Leone A, Freitas C, Oberman L, Horvath JC, Halko M, Eldaief M, Bashir S, Vernet M, Shafi M, Westover B, Vahabzadeh-Hagh AM, Rotenberg A. Characterizing brain cortical plasticity and network dynamics across the age-span in health and disease with TMS-EEG and TMS-fMRI. Brain Topogr 2011; 24:302-15. [PMID: 21842407 PMCID: PMC3374641 DOI: 10.1007/s10548-011-0196-8] [Citation(s) in RCA: 209] [Impact Index Per Article: 16.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2011] [Accepted: 07/27/2011] [Indexed: 01/21/2023]
Abstract
Brain plasticity can be conceptualized as nature's invention to overcome limitations of the genome and adapt to a rapidly changing environment. As such, plasticity is an intrinsic property of the brain across the lifespan. However, mechanisms of plasticity may vary with age. The combination of transcranial magnetic stimulation (TMS) with electroencephalography (EEG) or functional magnetic resonance imaging (fMRI) enables clinicians and researchers to directly study local and network cortical plasticity, in humans in vivo, and characterize their changes across the age-span. Parallel, translational studies in animals can provide mechanistic insights. Here, we argue that, for each individual, the efficiency of neuronal plasticity declines throughout the age-span and may do so more or less prominently depending on variable 'starting-points' and different 'slopes of change' defined by genetic, biological, and environmental factors. Furthermore, aberrant, excessive, insufficient, or mistimed plasticity may represent the proximal pathogenic cause of neurodevelopmental and neurodegenerative disorders such as autism spectrum disorders or Alzheimer's disease.
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Affiliation(s)
- Alvaro Pascual-Leone
- Berenson-Allen Center for Noninvasive Brain Stimulation, Division of Cognitive Neurology, Department of Neurology, Beth Israel Deaconess Medical Center, Harvard Medical School, 330 Brookline Avenue, Boston, MA 02215, USA.
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Freitas C, Perez J, Knobel M, Tormos JM, Oberman L, Eldaief M, Bashir S, Vernet M, Peña-Gómez C, Pascual-Leone A. Changes in cortical plasticity across the lifespan. Front Aging Neurosci 2011; 3:5. [PMID: 21519394 PMCID: PMC3079175 DOI: 10.3389/fnagi.2011.00005] [Citation(s) in RCA: 103] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2011] [Accepted: 03/23/2011] [Indexed: 12/21/2022] Open
Abstract
Deterioration of motor and cognitive performance with advancing age is well documented, but its cause remains unknown. Animal studies dating back to the late 1970s reveal that age-associated neurocognitive changes are linked to age-dependent changes in synaptic plasticity, including alterations of long-term potentiation and depression (LTP and LTD). Non-invasive brain stimulation techniques enable measurement of LTP- and LTD-like mechanisms of plasticity, in vivo, in humans, and may thus provide valuable insights. We examined the effects of a 40-s train of continuous theta-burst stimulation (cTBS) to the motor cortex (600 stimuli, three pulses at 50 Hz applied at a frequency of 5 Hz) on cortico-spinal excitability as measured by the motor evoked potentials (MEPs) induced by single-pulse transcranial magnetic stimulation before and after cTBS in the contralateral first dorsal interosseus muscle. Thirty-six healthy individuals aged 19–81 years old were studied in two sites (Boston, USA and Barcelona, Spain). The findings did not differ across study sites. We found that advancing age is negatively correlated with the duration of the effect of cTBS (r = −0.367; p = 0.028) and the overall amount of corticomotor suppression induced by cTBS (r = −0.478; p = 0.003), and positively correlated with the maximal suppression of amplitude on motor evoked responses in the target muscle (r = 0.420; p = 0.011). We performed magnetic resonance imaging (MRI)-based individual morphometric analysis in a subset of subjects to demonstrate that these findings are not explained by age-related brain atrophy or differences in scalp-to-brain distance that could have affected the TBS effects. Our findings provide empirical evidence that the mechanisms of cortical plasticity area are altered with aging and their efficiency decreases across the human lifespan. This may critically contribute to motor and possibly cognitive decline.
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Affiliation(s)
- Catarina Freitas
- Berenson-Allen Center for Noninvasive Brain Stimulation, Division of Cognitive Neurology, Department of Neurology, Beth Israel Deaconess Medical Center, Harvard Medical School Boston, MA, USA
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Abstract
The authors evaluated the 60-Second Test (SST), a brief test of mental concentration, as a supplement to the Glasgow Coma Scale (GCS) for monitoring verbally responsive patients in the neuro-intensive care unit. The SST demonstrated excellent reliability and was abnormal in 79% of patients assigned a top GCS score of 15. However, both tests had poor responsiveness to clinically identified changes in level of consciousness (LOC). The SST is sensitive to subtle alterations in LOC but, like the GCS, may have limitations as a monitoring tool in the neurocritical care setting.
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Affiliation(s)
- S A Mayer
- Division of Critical Care Neurology, College of Physicians and Surgeons, School of Public Health, Columbia University, New York, NY, USA.
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