ABSTRACT
This study aims to explore the auditory response characteristics of the thalamic reticular nucleus (TRN) in awake mice during auditory information processing, so as to deepen the understanding of TRN and explore its role in the auditory system. By in vivo electrophysiological single cell attached recording of TRN neurons in 18 SPF C57BL/6J mice, we observed the responses of 314 recorded neurons to two kinds of auditory stimuli, noise and tone, applied to mice. The results showed that TRN received projections from layer six of the primary auditory cortex (A1). Among 314 TRN neurons, 56.05% responded silently, 21.02% responded only to noise and 22.93% responded to both noise and tone. The neurons with noise response can be divided into three patterns according to their response time: onset, sustain and long-lasting, accounting for 73.19%, 14.49% and 12.32%, respectively. The response threshold of the sustain pattern neurons was lower than those of the other two types. Under noise stimulation, compared with A1 layer six, TRN neurons showed unstable auditory response (P < 0.001), higher spontaneous firing rate (P < 0.001), and longer response latency (P < 0.001). Under tone stimulation, TRN's response continuity was poor, and the frequency tuning was greatly different from that of A1 layer six (P < 0.001), but their sensitivity to tone was similar (P > 0.05), and TRN's tone response threshold was much higher than that of A1 layer six (P < 0.001). The above results demonstrate that TRN mainly undertakes the task of information transmission in the auditory system. The noise response of TRN is more extensive than the tone response. Generally, TRN prefers high-intensity acoustic stimulation.
Subject(s)
Rats , Mice , Animals , Wakefulness , Auditory Pathways/physiology , Rats, Wistar , Mice, Inbred C57BL , Thalamus/physiologyABSTRACT
OBJECTIVE@#To explore whether the characteristic responses to sound stimulations of the auditory neurons in the striatum is regulated in different behavioral states.@*METHODS@#The auditory neurons in the striatum of awake C57BL/6J mice were selected for this study. We recorded the auditory response of the striatum to noises over a long period of time by building a synchronous in vivo electrophysiological and locomotion recording system and using glass microelectrode attachment recording. By analyzing the running speed of the mice, the behavioral states of the mice were divided into the quiet state and the active state, and the spontaneous activity and evoked responses of the auditory neurons in the striatum were analyzed in these two states.@*RESULTS@#Compared with those recorded in the quiet state, the spontaneous activity of the auditory neurons in the striatum of the mice increased significantly (37.06±12.02 vs 18.51±10.91, P < 0.001) while the auditory response of the neurons decreased significantly (noise intensity=60 dB, 3.45±2.99 vs 3.04±2.76, P < 0.001) in the active state.@*CONCLUSION@#Locomotion has a significant inhibitory effect on the auditory response of the striatum, which may importantly contribute to the decline of sound information recognition ability in the active state.
Subject(s)
Animals , Mice , Acoustic Stimulation , Auditory Cortex/physiology , Evoked Potentials, Auditory , Locomotion/physiology , Mice, Inbred C57BL , NeuronsABSTRACT
This paper analyzed the limitation of electronic sphygmomanometer based on oscillometry, and according to the characteristics of pulse signal, the author proposed a new method of the characteristic parameter detection based on wavelet transform, and improved its recognition ability on fixed-scale, via resampling rate according to the heartbeat. And the prototype test has been proved that this method is more adaptability for individuals and stability for operation.