Robustness and Enhancement of Neural Synchronization by Activity-Dependent Coupling

Realistic Thermodynamic and Statistical-Mechanical Measures for Neural Synchronization

Synchronized brain rhythms, associated with diverse cognitive functions, have been observed in electrical recordings of brain activity. Neural synchronization may be well described by using the population-averaged global potential $V_G$ in computational neuroscience. The time-averaged fluctuation of $V_G$ plays the role of a "thermodynamic" order parameter $\cal {O}$ used for describing the synchrony-asynchrony transition in neural systems. Population spike synchronization may be well visualized in the raster plot of neural spikes. The degree of neural synchronization seen in the raster plot i…

Intracellular coupling modulates biflagellar synchrony

Beating flagella exhibit a variety of synchronization modes. This synchrony has long been attributed to hydrodynamic coupling between the flagella. However, recent work with flagellated algae indicates that a mechanism internal to the cell, through the contractile fibres connecting the flagella basal bodies, must be at play to actively modulate flagellar synchrony. Exactly how basal coupling mediates flagellar coordination remains unclear. Here, we examine the role of basal coupling in the synchronization of the model biflagellate \textit{Chlamydomonas reinhardtii} using a series of mathematic…

Dynamical Responses to External Stimuli for Both Cases of Excitatory and Inhibitory Synchronization in A Complex Neuronal Network

For studying how dynamical responses to external stimuli depend on the synaptic-coupling type, we consider two types of excitatory and inhibitory synchronization (i.e., synchronization via synaptic excitation and inhibition) in complex small-world networks of excitatory regular spiking (RS) pyramidal neurons and inhibitory fast spiking (FS) interneurons. For both cases of excitatory and inhibitory synchronization, effects of synaptic couplings on dynamical responses to external time-periodic stimuli $S(t)$ (applied to a fraction of neurons) are investigated by varying the driving amplitude $A$…

Synchronization and enhanced catalysis of mechanically coupled enzymes

We examine the stochastic dynamics of two enzymes that are mechanically coupled to each other, e.g., through an elastic substrate or a fluid medium. The enzymes undergo conformational changes during their catalytic cycle, which itself is driven by stochastic steps along a biased chemical free energy landscape. We find conditions under which the enzymes can synchronize their catalytic steps, and discover that the coupling can lead to a significant enhancement in their overall catalytic rate. Both effects can be understood as arising from a global bifurcation in the underlying dynamical system a…

由于酶活性导致的胶体示踪剂扩散增强

Enhanced diffusion of colloidal tracers due to enzymatic activity

研究酶活性对胶体示踪剂扩散的影响，通过结合差分动态显微镜和光镊测量，比较不同配置、不同大小示踪剂的情况，发现酶活性可转换为微观运动和力，增强效果受多种因素影响，对理解非平衡动力学有重要意义。

力学促进异质活性介质中的相干性

Mechanics promotes coherence in heterogeneous active media

该研究针对异质心肌细胞集合的自组织协调问题，通过改变细胞间耦合与电生理多样性揭示多种集体行为，并发现牵张激活电流介导的力学作用可促进全局相干性，为理解器官生理同步提供力学视角。

小世界网络上 FitzHugh-Nagumo 振子类癫痫间歇性活动起始时的极端事件

Extreme events at the onset of epileptic-like intermittent activity of FitzHugh-Nagumo oscillators on small-world networks

研究 Watts-Strogatz 小世界网络中 FitzHugh-Nagumo 振子的四相动力学，发现极端同步事件峰值可预示类癫痫间歇相及同步转变。