Center for Music in the Brain, Department of Clinical Medicine, Aarhus University & The Royal Academy of Music, Aarhus/Aalborg, Aarhus, Denmark.
Centre for Eudaimonia and Human Flourishing, Linacre College, University of Oxford, Oxford, UK.
Commun Biol. 2024 Aug 29;7(1):1036. doi: 10.1038/s42003-024-06587-7.
Aging is often associated with decline in brain processing power and neural predictive capabilities. To challenge this notion, we used magnetoencephalography (MEG) and magnetic resonance imaging (MRI) to record the whole-brain activity of 39 older adults (over 60 years old) and 37 young adults (aged 18-25 years) during recognition of previously memorised and varied musical sequences. Results reveal that when recognising memorised sequences, the brain of older compared to young adults reshapes its functional organisation. In fact, it shows increased early activity in sensory regions such as the left auditory cortex (100 ms and 250 ms after each note), and only moderate decreased activity (350 ms) in medial temporal lobe and prefrontal regions. When processing the varied sequences, older adults show a marked reduction of the fast-scale functionality (250 ms after each note) of higher-order brain regions including hippocampus, ventromedial prefrontal and inferior temporal cortices, while no differences are observed in the auditory cortex. Accordingly, young outperform older adults in the recognition of novel sequences, while no behavioural differences are observed with regards to memorised ones. Our findings show age-related neural changes in predictive and memory processes, integrating existing theories on compensatory neural mechanisms in non-pathological aging.
衰老通常与大脑处理能力和神经预测能力的下降有关。为了挑战这一观点，我们使用脑磁图（MEG）和磁共振成像（MRI）记录了 39 名老年人（60 岁以上）和 37 名年轻人（18-25 岁）在识别先前记忆和多样化音乐序列时的全脑活动。结果表明，在识别记忆序列时，老年人的大脑相对于年轻人重塑了其功能组织。事实上，它在左听觉皮层等感觉区域显示出更早的活动增加（每个音符后 100 毫秒和 250 毫秒），而在中颞叶和前额叶区域仅适度减少活动（350 毫秒）。当处理多样化的序列时，老年人表现出高阶大脑区域（包括海马体、腹内侧前额叶和下颞叶皮质）快速尺度功能（每个音符后 250 毫秒）的明显减少，而听觉皮层则没有差异。相应地，年轻人在识别新序列方面优于老年人，而在记忆序列方面则没有观察到行为差异。我们的发现表明，在预测和记忆过程中存在与年龄相关的神经变化，整合了关于非病理性衰老中补偿性神经机制的现有理论。
