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Cortical populations produce complex spatiotemporal activity spontaneously without sensory inputs. However, the fundamental computational roles of such spontaneous activity remain unclear. Here, we propose a new neural computation mechanism for understanding how spontaneous activity is actively involved in cortical processing: Computing by Modulating Spontaneous Activity (CMSA). Using biophysically plausible circuit models, we demonstrate that spontaneous activity patterns with dynamical properties, as found in empirical observations, are modulated or redistributed by external stimuli to give rise to neural responses. We find that this CMSA mechanism of generating neural responses provides profound computational advantages, such as actively speeding up cortical processing. We further reveal that the CMSA mechanism provides a unifying explanation for many experimental findings at both the single-neuron and circuit levels, and that CMSA in response to natural stimuli such as face images is the underlying neurophysiological mechanism of perceptual “bubbles” as found in psychophysical studies., The brain’s cortex shows complex activity patterns in the absence of sensory inputs. Here, using computational modelling, the authors demonstrate that cortical spontaneous activity is modulated by sensory input and that this modulation process underlies active visual processing.

Two-dimensional graphene is easy to aggregate and hard to transfer because of the van der Waals forces between graphene layers. The three-dimensional (3D) graphite-like capsules (GCs) disperse well and exhibit robust structural stability and have a potential for promising applications in energy storage, drug delivery, catalyst substrate, etc. Here, we develop a catalytic chemical vapor deposition route for the synthesis of 3D GCs with unprecedented thickness and morphology control. The theoretical results indicate that the strong chemisorption and charge transfer between ZnO and acetylene allow the layer-by-layer formation of GCs that is later confirmed by the experimental data. The 3D GCs are synthesized with thickness control from three atomic layers to ∼300 atomic layers over various oxides with predesigned shapes of microscale tetrapods, nanospheres, nanorods, nanocubes, etc. In particular, the formation mechanism of GCs is investigated using the ZnO surface as a catalyst through systematically experi...

The facile preparation of ZnO possessing high visible luminescence intensity remains challenging due to an unclear luminescence mechanism. Here, two basic approaches are proposed to enhance the luminescent intensity based on the theoretical analysis over surface defects. Based on the deduction, we introduce a methodology for obtaining hybrid tetrapod-like zinc oxide (T-ZnO), decorated by carbon nanomarterials on T-ZnO surfaces through the catalytic chemical vapor deposition approach. The intensity of the T-ZnO green emission can be modulated by topography and the proportion of carbon. Under proper experiment conditions, the carbon decorating leads to dramatically enhanced luminescence intensity of T-ZnO from 400 to 700 nm compared with no carbon decorated, which elevates this approach to a simple and effective method for the betterment of fluorescent materials in practical applications.