Transcranial magnetic stimulation reveals diminished homoeostatic metaplasticity in cognitively impaired adults.
Transcranial magnetic stimulation reveals diminished homoeostatic metaplasticity in cognitively impaired adults.
复制标题
DOI：
10.1093/braincomms/fcaa203
复制
发表时间：
2020
影响因子：
4.8
通讯作者：
Chou YH
中科院分区：
文献类型：
--
作者：
Sundman MH;Lim K;Ton That V;Mizell JM;Ugonna C;Rodriguez R;Chen NK;Fuglevand AJ;Liu Y;Wilson RC;Fellous JM;Rapcsak S;Chou YH
同源稳态亚可塑性是一种神经保护性生理特征，其平衡赫布形式的可塑性以防止网络不稳定和过度兴奋。最近的动物模型强调了阿尔茨海默病发病机制中的功能失调的同源性亚可塑性。然而，在痴呆或非痴呆人群中，同源性后可塑性与认知状态之间的关联尚未得到系统表征，并且同源性后可塑性作为认知障碍的早期生物标志物的潜在价值尚未在人类中探索。在这里，我们报告说，通过预处理的突触活动之前，非侵入性脑刺激，同源性超可塑性和认知状态之间的关联可以建立在一个人口的非痴呆症的人类受试者（老年人跨认知频谱;所有在非痴呆症的范围内）。所有参与者（n = 40;年龄范围，65-74岁，47.5%女性）接受了标准化神经心理电池，磁共振成像和经颅磁刺激方案。具体来说，我们采样运动诱发电位与输入/输出曲线之前和之后立即重复经颅磁刺激，以评估神经可塑性与两个实验范例：一个自愿肌肉收缩（即调制的突触活动历史）故意引入homoestatic干扰，和一个没有作为控制条件。通过比较这些实验范式和按认知状态分组的队列中的神经可塑性反应，我们发现（i）在我们的认知受损老年人队列中同源性亚可塑性减弱，（ii）这种神经保护功能在认知正常的参与者中保持完整。这一新的发现表明，（i）未来的研究应扩大其范围，不仅仅是传统上使用非侵入性脑刺激来研究认知老化时评估的赫布形式的可塑性，（ii）应进一步探索同型稳态后可塑性作为认知障碍生物标志物的潜在价值。神经可塑性进行了评估，在健康的老年人与TMS。根据神经心理学评估，使用经验证的认知功能障碍截止值对参与者进行分层。Sundman等人观察到不同的神经可塑性特征，特别是当刺激之前有突触预处理时。这表明可塑性机制可能与认知能力下降有关。
Homoeostatic metaplasticity is a neuroprotective physiological feature that counterbalances Hebbian forms of plasticity to prevent network destabilization and hyperexcitability. Recent animal models highlight dysfunctional homoeostatic metaplasticity in the pathogenesis of Alzheimer’s disease. However, the association between homoeostatic metaplasticity and cognitive status has not been systematically characterized in either demented or non-demented human populations, and the potential value of homoeostatic metaplasticity as an early biomarker of cognitive impairment has not been explored in humans. Here, we report that, through pre-conditioning the synaptic activity prior to non-invasive brain stimulation, the association between homoeostatic metaplasticity and cognitive status could be established in a population of non-demented human subjects (older adults across cognitive spectrums; all within the non-demented range). All participants (n = 40; age range, 65–74, 47.5% female) underwent a standardized neuropsychological battery, magnetic resonance imaging and a transcranial magnetic stimulation protocol. Specifically, we sampled motor-evoked potentials with an input/output curve immediately before and after repetitive transcranial magnetic stimulation to assess neural plasticity with two experimental paradigms: one with voluntary muscle contraction (i.e. modulated synaptic activity history) to deliberately introduce homoeostatic interference, and one without to serve as a control condition. From comparing neuroplastic responses across these experimental paradigms and across cohorts grouped by cognitive status, we found that (i) homoeostatic metaplasticity is diminished in our cohort of cognitively impaired older adults and (ii) this neuroprotective feature remains intact in cognitively normal participants. This novel finding suggests that (i) future studies should expand their scope beyond just Hebbian forms of plasticity that are traditionally assessed when using non-invasive brain stimulation to investigate cognitive ageing and (ii) the potential value of homoeostatic metaplasticity in serving as a biomarker for cognitive impairment should be further explored. Neural plasticity was assessed in healthy older adults with TMS. Upon neuropsychological evaluation, participants were stratified using validated cutoffs for cognitive dysfunction. Sundman et al. observed divergent neural plasticity profiles, particularly when stimulation was preceded by synaptic pre-conditioning. This suggests that mechanisms of metaplasticity may be associated with cognitive decline.
登录
查看更多内容
地球是平的（p > 0.05）：重要性阈值和不可复制研究的危机。
影响因子：
2.7
作者：
Amrhein V;Korner-Nievergelt F;Roth T
通讯作者：
Roth T
影响因子：
3.9
作者：
Freitas, Catarina;Mondragon-Llorca, Helena;Pascual-Leone, Alvaro
通讯作者：
Pascual-Leone, Alvaro
影响因子：
3
作者：
Craddock, Matt;Klepousniotou, Ekaterini;Lloyd, Donna
通讯作者：
Lloyd, Donna
影响因子：
5.5
作者：
Cheeran, Binith;Talelli, Penelope;Rothwell, John C.
通讯作者：
Rothwell, John C.
DOI：
10.1016/j.neucli.2015.12.003
发表时间：
2016-02-01
影响因子：
3
作者：
Cueva, Ana Sofia;Galhardoni, Ricardo;de Andrade, Daniel Ciampi
通讯作者：
de Andrade, Daniel Ciampi