The role of awareness in differential delay eyeblink conditioning （DEC） remains controversial. Here, we investigated the involvement of awareness in differential DEC with a soft or a loud tone as the conditioned sti...The role of awareness in differential delay eyeblink conditioning （DEC） remains controversial. Here, we investigated the involvement of awareness in differential DEC with a soft or a loud tone as the conditioned stimulus （CS）. In the experiment, 36 participants were trained in differential DEC with a soft tone （60 dB） or a loud tone （85 dB） as the CS, paired with a corneal air-puff as the unconditioned stimulus （US）. After conditioning, awareness of the relationship between assessed with a 17-item the CS and the US was true/false questionnaire. Interestingly, during differential DEC with a soft-tone CS, a higher proportion of differential conditioned responses （CRs） was evident in participants who were aware than those who were unaware. In contrast, when a loud tone was used as the CS, the proportion of differential CRs of the aware participants did not differ significantly from those who were unaware over any of the blocks of 20 trials. In unaware participants, the percentage of differential CRs with a loud-tone CS was significantly higher than that with a soft-tone CS; however in participants classified as aware, the percentage of differential CRs with a loud-tone CS did not differ significantly from that with a soft-tone CS. The present findings suggest that awareness is critical for differential DEC when the delay task is rendered more difficult.展开更多
针对现有正交频分复用(Orthogonal Frequency Division Multiplexing,OFDM)系统峰均比(Peak to Averaye Power Ratio,PAPR)抑制方法中子载波预留技术只是预留未承载数据的空子载波,没有考虑预留子载波功率分配的问题,提出了一种通过牛...针对现有正交频分复用(Orthogonal Frequency Division Multiplexing,OFDM)系统峰均比(Peak to Averaye Power Ratio,PAPR)抑制方法中子载波预留技术只是预留未承载数据的空子载波,没有考虑预留子载波功率分配的问题,提出了一种通过牛顿迭代法对预留子载波进行功率分配来降低PAPR的方法.该方法通过把预留子载波降低PAPR的过程归纳为一阶线性展开时域模型和离散功率谱频域模型的软限幅过程,通过时域限幅,频域滤波操作生成初始预留子载波信号,以信号失真功率比(Signal to Distortion and Noise Rutio,SDNR)最大化为目标函数,运用牛顿迭代法对预留子载波进行功率分配.仿真结果表明,该方法能有效降低峰均比,在载波数为256,预留载波数分别为16和32的条件下,峰均比抑制效果分别改善了4.0d B和4.3d B.展开更多
基金supported by the National Natural Science Foundation of China (81171249)
文摘The role of awareness in differential delay eyeblink conditioning （DEC） remains controversial. Here, we investigated the involvement of awareness in differential DEC with a soft or a loud tone as the conditioned stimulus （CS）. In the experiment, 36 participants were trained in differential DEC with a soft tone （60 dB） or a loud tone （85 dB） as the CS, paired with a corneal air-puff as the unconditioned stimulus （US）. After conditioning, awareness of the relationship between assessed with a 17-item the CS and the US was true/false questionnaire. Interestingly, during differential DEC with a soft-tone CS, a higher proportion of differential conditioned responses （CRs） was evident in participants who were aware than those who were unaware. In contrast, when a loud tone was used as the CS, the proportion of differential CRs of the aware participants did not differ significantly from those who were unaware over any of the blocks of 20 trials. In unaware participants, the percentage of differential CRs with a loud-tone CS was significantly higher than that with a soft-tone CS; however in participants classified as aware, the percentage of differential CRs with a loud-tone CS did not differ significantly from that with a soft-tone CS. The present findings suggest that awareness is critical for differential DEC when the delay task is rendered more difficult.
文摘针对现有正交频分复用(Orthogonal Frequency Division Multiplexing,OFDM)系统峰均比(Peak to Averaye Power Ratio,PAPR)抑制方法中子载波预留技术只是预留未承载数据的空子载波,没有考虑预留子载波功率分配的问题,提出了一种通过牛顿迭代法对预留子载波进行功率分配来降低PAPR的方法.该方法通过把预留子载波降低PAPR的过程归纳为一阶线性展开时域模型和离散功率谱频域模型的软限幅过程,通过时域限幅,频域滤波操作生成初始预留子载波信号,以信号失真功率比(Signal to Distortion and Noise Rutio,SDNR)最大化为目标函数,运用牛顿迭代法对预留子载波进行功率分配.仿真结果表明,该方法能有效降低峰均比,在载波数为256,预留载波数分别为16和32的条件下,峰均比抑制效果分别改善了4.0d B和4.3d B.
