Objective Cortical processing ofsomatosensory information is performed by a large population of neurons with complex dynamics and interactions in barrel cortex.Emerging evidences recently suggest that astrocytes receive surrounding synaptic inputs and participate in sensory information processing.However, the knowledge of population response dynamics and functional connectivity on processing tactile frequency information in barrel cortex at the level of neuro-astrocytic microcircuits remains comparably poor.A key step to understand the complex mechanisms of how these nerve cells work is measuring and analyzing the dynamic interactions in the local microcircuits in vivo under different conditions of sensory stimulation.Hence, we used two-photon calcium imaging to monitor the neuronal and astrocytic activities in barrel microcircuit, which would help to explore the processing mechanisms for tactile frequency discrimination.Methods FVB mice (20-35 PND) were anesthetized by the intraperitoneal injections of urethane.A population ofneocortical cells was labeled by injecting the calcium indicator Oregon Green BAPTA-1 AM into layer Ⅰ and Ⅱ/Ⅲ.Astrocytes were distinguished by co-injecting the astrocytic specific marker sulforhodamine 101.Population neuronal and astrocytie calcium signals in barrel microcircuit were simultaneously recorded in vivo by two-photon laser scanning microscopy with the resolution of individual cells.Whiskers of FVB mice in the contralateral sides of the imaged barrel cortices were deflected in a caudal-to-rostral direction by air-puffing during the experiments.Whisker deflections were done by giving the paired repetitive pulses of air-puffing (50 psi, 50 ms) through a tiny steel tube that was mounted on a micromanipulator and controlled with costume-made LabVIEW program.The stimulus patterns were paired bursts that constituted of frequency patterns as 10 and 10 Hz (named as 10-to-10 Hz) or 8 and 12 Hz (i.e., 8-to-12 Hz), closely to the natural frequency of exploratory whisking.The coordination of population calcium dynamics and network topologic properties were analyzed based on graph theory.Results (1) Compared with the spontaneous conditions, whiskers deflections evoked much larger calcium signals in both neurons and astrocytes and increased the activity synchronization in neuronal and astrocytic network.(2) The majority of neuronal and astrocytic responses was both facilitated by frequency increment of whiskers inputs and depressed with the adaptation.(3) Neurons and astrocytes in local networks were coordinately activated, thus forming functional neuro-astrocytic network.(4) The strength of functional connectivity in neuro-astrocytic network was enhanced with frequency increment and weakened with adaptation.Conclusion The dynamic changes of responses and functional connectivity in barrel neuro-astrocytic network may contribute to frequency-dependent processing of whisker sensory information.