Very fast ripples (VFRs, 500–1000[Formula: see text]Hz) are considered more specific than high-frequency oscillations (80–500[Formula: see text]Hz) as biomarkers of epileptogenic zones. Although VFRs are frequent abnormal phenomena in epileptic seizures, their functional roles remain unclear. Here, we detected the VFRs in the hippocampal network and tracked their roles during status epilepticus (SE) in rats with pilocarpine-induced temporal lobe epilepsy (TLE). All regions in the hippocampal network exhibited VFRs in the baseline, preictal, ictal and postictal states, with the ictal state containing the most VFRs. Moreover, strong phase-locking couplings existed between VFRs and slow oscillations (1–12[Formula: see text]Hz) in the ictal and postictal states for all regions. Further investigation indicated that during VFRs, the build-up of slow oscillations in the ictal state began from the temporal lobe and then spread through the whole hippocampal network via two different pathways, which might be associated with the underlying propagation of epileptiform discharges in the hippocampal network. Overall, we provide a functional description of the emergence of VFRs in the hippocampal network during SE, and we also establish that VFRs may be the physiological representation of the pathological alterations in hippocampal network activity during SE in TLE.

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Reasonable image enhancement and image segmentation technologies help people to identify the object from original images, which cannot be easily recognized by naked eyes. A method of image recognition based on improved histogram equalization and image segmentation was proposed in this paper. By stretching the histogram in a custom range and excluding singular points, contrast of images was enhanced with more detail information. Then, feature vector in different color space was used to segment the object from original images. From testing, this method was proved to be efficient, simple and convenient to implement and can be used in real time system because of its simplicity.