Scientific Programme
Biomechanics & Motor control
IS-BM07 - The aging brain in motor control and balance learning: from molecules to neurons and networks
Date: 02.07.2025, Time: 13:15 - 14:30, Session Room: Castello 1
Description
Age-related changes in motor functions manifest across multiple neuroscientific levels. Metabolically, Magnetic Resonance Spectroscopy (MRS) reveals shifts in key neurochemicals such as declines in N-acetylaspartate glutamat and GABA, as well as increases in creatine+phosphocreatine and choline with the increases in aging. These changes can disrupt motor control and execution. Magnetic Resonance Imaging (MRI) shows notable age-related decline in both gray and white matter. The motor cortex, but also other cortical and subcortical areas critical for initiating and refining movement—experience volume reduction and more subtle microstructural changes. These structural changes contribute directly to declines in mobility and balance often observed in older adults. Functionally, the brain adapts to these changes by reduced inhibitory processes and accompanied overactivation of motor areas. This loss of balance between excitation and inhibition impacts motor control of older adults contributing to a reduced physical function. Together, these metabolic, structural, and functional changes provide a comprehensive view of how aging impacts motor abilities. With this session we aim to cover a broad range of current research on age-related alteration in brain structure and function and how these changes are related to motor functioning. Finally, we will address how physical activity interventions can help to counteract these age-related declines in physical function.
Chair(s)
Benedikt Lauber
University of Fribourg, Department of Neurosciences and Movement Sciences
Switzerland
Speaker A
Benedikt Lauber
University of Fribourg, Department of Neurosciences and Movement Sciences
Switzerland
Read CVECSS Rimini 2025: IS-BM07
Rebalance the brain: the effect of aging and physical activity on cortical inhibition and excitation
Aging is a natural physiological process that leads to changes in function, which can result in reduced motor performance, cognitive decline, and impaired motor learning and consolidation. However, contrary to mid-20th-century beliefs, healthy aging is not associated with the same widespread neural loss seen in neurodegenerative diseases. As a result, there is growing interest in understanding how aging affects specific neural subpopulations and their synaptic connections. In particular, research on age-related changes in inhibitory neurons, which represent the most complex and diverse group of brain cells playing a critical role in modulating the activity of entire neural circuits, is considered crucial. Gamma-aminobutyric acid (GABA), one, if not the main inhibitory neurotransmitter in the central nervous system, is used by approximately one-third of neurons as their main form of communication. It appears that aging is associated with a decline in global GABA levels across in various brain regions and this decline in GABAergic function results in an imbalance between inhibitory and excitatory activity, disrupting multiple brain circuits. As a consequence, it impairs not only motor and cognitive behaviors but also neural plasticity. It is important to note that not only GABA concentration plays an important role but also the ability to task-specifically up- or downregulate intracortical inhibition is important. It was for example shown that skilled experts (e.g. piano and badminton players) were able to modulate intracortical inhibition in a task-specific fashion whereas novices showed much less modulation indicating that with motor learning, inhibitory processes can be modulated. With respect to aging, recent evidence suggest that longer training periods can also cause changes in the modulary capacity of the brain and that these in intracortical inhibition are associated with improvements in performance. In this talk, I will address the importance of the cortical inhibitory network for motor control and motor learning and how aging and certain pathologies affect these inhibitory networks causing an imbalance between cortical excitation and inhibition. Furthermore, I will address how motor learning (e.g. balance learning, strength training) in general and particularly in the elderly will affect cortical inhibition and how the changes in the cortical inhibitory network might be related to other outcome measure such as sleep quality.
Speaker B
Nico Lehmann
Otto von Guericke University Magdeburg, Institute III, Department of Sport Science
Germany
Read CVECSS Rimini 2025: IS-BM07
Postural control, balance training and the (micro-)structure of the aging brain: the case for quantitative MRI
Age-related deterioration in postural control is an important factor decreasing quality of life. A healthy brain, characterized by intact gray (GM) and white matter (WM), is vital for the efficient functioning of neural networks during daily life tasks, thus playing a critical role in maintaining and restoring mobility and balance in aging. Atrophy, which is usually measured based on structural magnetic resonance imaging (MRI), is one of the most important changes in healthy and especially in pathological aging of the brain. Consequently, most MRI studies investigating age-related changes in balance performance (including falls) and balance training-induced neuroplasticity focused on meso- and macroscopic shape of the brain as assessed with T1-weighted imaging (morphometric analysis). Usually, the volumes of the cortex and/or sub-cortical gray matter are measured and correlated with balance performance, or tracked longitudinally. When reviewing the results from these studies, it becomes clear that a comprehensive understanding of postural control and balance can only be achieved by studying distributed cortical and subcortical brain areas and their interconnecting fibre tracts, whereby the latter in particular have been largely neglected to date. A further problem is that the conventional analysis approach is relatively unspecific with regard to neurobiological tissue properties, since morphometric results also depend on cortical thickness, surface area and tissue density. Last but not least, since microstructural changes in the brains of older people, specifically pertaining to synapses, typically precede meso- and macroscopic atrophy, it is likely that the morphometric analysis approach has also limited sensitivity to detect training-induced changes and brain-behavior correlations. As a possible way forward, I will discuss how quantitative multicontrast MRI weighted towards diffusion, relaxation times and magnetisation transfer can be used in combination with advanced biophysical modelling to address these problems. The unprecedented insights into the relationship between GM/ WM microstructure and balance offered by such a novel approach are demonstrated based on unpublished data from two randomised controlled trials of balance training in older adults in which our laboratory was involved. I will draw attention to how multivariate combinations of MRI-derived metrics can uncover microstructural information that is typically concealed when focusing on single metrics, and I will discuss neuroplasticity and brain-behavior correlations against the background of previous studies. It is hoped that these novel multicontrast estimates of brain anatomy (“in-vivo histology”) will be increasingly used in the field of movement neuroscience, with potential applications in early diagnosis, guiding treatment and assessing individual response to training and therapy.
Metabolic Changes in Aging: Current Evidence and the Impact of Physical Activities
Aging affects brain structure, function, and metabolism, often leading to declines in cognition and motor performance. Proton magnetic resonance spectroscopy (¹H MRS) is a valuable non-invasive tool for studying age-related brain metabolite changes. Current studies focus on key metabolites such as N-acetylaspartate (NAA), linked to neuronal health; choline-containing compounds (Cho), involved in cell membrane and myelin metabolism; myo-inositol (mI), a glial marker and osmolyte; glutamate and GABA, the major excitatory and inhibitory neurotransmitters, and creatine (Cr), an energy metabolite. Decreases in NAA and increases in mI have been consistently observed with age, suggesting possible neural loss in grey matter, axonal damage in white matter, demyelination, inflammation, or glial activation. As the brain consumes high levels of energy, it is sensitive to ATP (adenosine triphosphate) fluctuations. ATP production and energy transport are essential for supporting neural function. Mitochondrial ATP is mainly synthesized through ATP synthase, using adenosine diphosphate (ADP) and inorganic phosphate (Pi). Phosphorus magnetic resonance spectroscopy (³¹P MRS) measures phospho-metabolites involved in energy and membrane phospholipid metabolism, supporting the study of neuroenergetics and brain health. Our previous study revealed a metabolic network linking NAD metabolism with phospholipid turnover, energy production, and aging. Comparing younger and older subjects, we observed distinct metabolic profiles, including increased PCr, glycerophosphocholine (GPC), and glycerophosphoethanolamine (GPE) levels, alongside a rise in ATP synthase activity and declines in ATP and phosphoethanolamine (PE) levels. These findings highlight ³¹P MRS as a powerful tool to uncover metabolic changes, supporting new therapeutic approaches targeting energy pathways in aging. Moreover, MRS can monitor energy metabolism and biochemical changes during cognitive or motor tasks, enabling analysis of activity-induced metabolic shifts. So far, a key question to address in aging-related brain research is whether motor learning can counteract brain changes associated with aging. Balance learning, a promising intervention, has been shown to enhance postural stability, structural and functional connectivity adaptations. However, most studies focus on young adults, it remains unclear if similar plasticity effects occur in older adults and what is underlying molecular mechanism. In this talk, I will first give an overview about age-related metabolic changes, focusing on neurotransmitters and energy metabolites, and then explore how advanced MRS techniques can map regional and functional brain changes. Finally, I will share findings from our recent study on long-term balance and strength training in older adults, examining how physical training may enhance brain metabolism and counteract aging‐related decline in motor performance.