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Zhou, Y. J.

Publications and source records attributed to Zhou, Y. J..

3 recordsLinked to original sources

Data-driven oscillatory network modeling with condition-dependent coupling laws: Identifying directed neural interactions in working memory attention dynamics

Learning new information in the presence of distracters and changing conditions requires the ability to adapt. In the brain, this adaptive capability has been linked to dynamic interactions between attention and working memory, which enable the selective filtering of irrelevant input while preserving behaviorally relevant information. Specific neural oscillations have been implicated in this process. Here, we introduce a phenomenological data-driven framework for oscillatory network modeling that learns condition-dependent coupling laws directly from neural recordings and enables inference of condition-dependent directed pathways. We apply our approach to magnetoen-cephalography (MEG) data collected while participants performed a working-memory task with and without distracters. Recall dynamics in the non-distracter condition are first modeled using a linear oscillatory network in which each region of interest is represented by two alpha-band harmonic oscillators. We use universal differential equations (UDE), an extension of neural differential equations, to capture distracter-induced changes in coupling laws. Symbolic regression is then used to interpret the modifications identified by UDE as nonlinear functions, and an additional method is proposed to identify the directed pathway from the newly emerging nonlinear terms in the dynamics of brain regions of interest. Despite inter-subject variability, working memory recall data from all four participants examined under distraction showed the emergence of a pathway from the dorsolateral prefrontal cortex (dlPFC) to the primary visual cortex (V1). This finding is consistent with the established role of the dlPFC in cognitive control and suggests that distracter processing recruits a directed interaction from prefrontal to visual regions. More broadly, our results illustrate that combining linear models whose parameters are learned from the data with universal differential equations augmented by interpretability methods enables the identification of condition-dependent coupling laws, their representation as interpretable mathematical functions, and the discovery of candidate directed pathways underlying adaptive changes in oscillatory networks without requiring strong prior assumptions about the underlying mechanisms.

neuroscience↗

Evolutionary history of the α-Carbonic Anhydrase (αCA) gene family in the phylum Arthropoda, with a focus on the copepod Eurytemora affinis species complex

The -Carbonic Anhydrase (CA) gene family encodes an abundant and ancient metalloenzyme present in all animals. Found in both eukaryotes and prokaryotes, members of this gene family play vital roles in ionic regulation, acid-base regulation, and respiration. However, little is known regarding the evolutionary history and patterns of molecular evolution of this gene family in the phylum Arthropoda. Through phylogenetic reconstruction and subcellular localization prediction, we discovered that arthropod CA genes could be classified into three clades based on phylogenetic topology and predicted subcellular localization, as has been found in chordate CA. Within the three distinct arthropod CA clades, the Extracellular & Membrane-bound CA clade exhibited the highest rates of evolution, variation in predicted subcellular localization, and number of homologs. Intriguingly, while we found that the majority of arthropod CA homologs were classified in the Extracellular & Membrane-bound CA clade, the majority of chordate CA were within the Cytosolic CA clade. This result indicates divergence in CA expansion patterns between the two phyla. In addition, we found that CA12, a paralog that showed salinity-associated signatures of selection in the copepod Eurytemora affinis species complex in previous studies, also shows signatures of positive selection (based on dN/dS) in two of the three sister species of the copepod Eurytemora affinis species complex (E. carolleeae and E. gulfia), compared to the general arthropod CA background. Overall, our results indicate that the CA gene family shows signatures of selection at the macroevolutionary scale, across phyla, and between closely related sister species. Significance statementAlpha Carbonic Anhydrase (CA) is an essential enzyme that is particularly well-studied among certain metazoan lineages, such as chordates and poriferans, but not in arthropods. Here, we provide the first comprehensive analysis of the evolutionary history of CA, and uncover the signatures of selection across phylum and between species. Through phylogenetic reconstruction, predicted subcellular localization, and dN/dS-based selection tests, our study shed light on how the CA gene family has and continues to evolve in the largest animal phylum Arthropoda.

evolutionary biology↗

Alpha oscillations shape sensory representation and perceptual accuracy

Alpha activity (8-14 Hz) is the dominant rhythm in the awake brain, and thought to play an important role in setting the brains internal state. Previous work has associated states of decreased alpha power with enhanced neural excitability. However, evidence is mixed on whether and how such excitability enhancement modulates sensory signals of interest versus noise differently, and what, if any, the consequences are for subsequent perception. Here, human subjects (male and female) performed a visual detection task in which we manipulated their decision criteria in a block-wise manner. While our manipulation led to substantial criterion shifts, these shifts were not reflected in pre-stimulus alpha-band changes. Rather, lower pre-stimulus alpha power in occipital-parietal areas improved perceptual sensitivity and enhanced information content decodable from neural activity patterns. Additionally, oscillatory alpha phase immediately before stimulus presentation modulated accuracy. Together, our results suggest that alpha-band dynamics modulate sensory signals of interest more strongly than noise. Significance statementThe internal state of our brain fluctuates, giving rise to variability in perception and action. Neural oscillations, most prominently in the alpha-band, have been suggested to play a role in setting this internal state. Here, we show that ongoing alpha-band activity in occipital-parietal regions predicts the quality of visual information decodable in neural activity patterns, and subsequently human observers sensitivity in a visual detection task. Our results provide comprehensive evidence that visual representation is modulated by ongoing alpha-band activity, and advance our understanding on how, when faced with unchanging external stimuli, internal neural fluctuations influence perception and behavior.

neuroscience↗