Selectivity for echo spectral interference and delay in the auditory cortex of the big brown bat Eptesicus fuscus.
Selectivity for echo spectral interference and delay in the auditory cortex of the big brown bat Eptesicus fuscus.
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大棕蝠 Eptesicus fuscus 听觉皮层回声频谱干扰和延迟的选择性。
DOI：
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发表时间：
2002
影响因子：
2.5
通讯作者：
J. Simmons
中科院分区：
文献类型：
--
作者：
M. Sanderson;J. Simmons
回声定位蝙蝠的声学环境可以包含多个物体，这些物体反射的回声在时间上如此接近，以至于它们几乎完全重叠。这导致单个回波的频谱特征在于由于干扰而产生的深凹口。本研究的目的是记录可能的选择性，或缺乏听觉神经元的时间分离的生物声纳信号的粗（毫秒）和细（微米）的时间尺度。我们记录了大棕蝙蝠听觉皮层的单单位活动，同时提出了四个协议设计使用宽带FM信号。协议模拟了一对部分重叠的回波，其中第一回波和第二回波之间的间隔在0和72微秒之间变化，脉冲之后是从0到30 ms的变化延迟的单个回波，脉冲之后是具有0-72微秒的变化时间间隔的一对部分重叠的回波，并且脉冲之后是，具有0到30 ms之间的变化延迟，通过一对回波，该回波本身在微秒时间尺度上具有固定的时间间隔。大约一半的皮层单位显示出增加的尖峰计数对部分重叠的回声在特定的分离（6-72微米）相比，在0微米分离的基线刺激。对于许多神经元测试与脉冲后，两个重叠的回声，我们观察到的脉冲和重叠的回声对之间的粗延迟和两个回声本身之间的分离的敏感性。对两个回波之间的部分重叠的灵敏度没有调整到单个时间间隔。对于蝙蝠来说，这意味着到最近反射器的绝对距离和反射器之间的距离可以在一小群单个单元中联合编码。有几种可能的神经机制用于基于对频谱陷波的敏感性来编码两个附近回波之间的分离。
The acoustic environment for an echolocating bat can contain multiple objects that reflect echoes so closely separated in time that they are almost completely overlapping. This results in a single echo with a spectrum characterized by deep notches due to interference. The object of this study was to document the possible selectivity, or lack thereof, of auditory neurons to the temporal separation of biosonar signals on a coarse (ms) and fine (micros) temporal scale. We recorded single-unit activity from the auditory cortex of big brown bats while presenting four protocol designs using wideband FM signals. The protocols simulated a pair of partially overlapping echoes where the separation between the first and second echo varied between 0 and 72 micros, a pulse followed by a single echo at varying delay from 0 to 30 ms, a pulse followed at a fixed delay by a pair of partially overlapping echoes that had a varying temporal separation of 0-72 micros, and a pulse followed, with a varying delay between 0 and 30 ms, by a pair of echoes that themselves had a fixed temporal separation on a microsecond time scale. About half of the cortical units showed increased spike counts to pairs of partially overlapping echoes at particular separations (6-72 micros) compared with a baseline stimulus at 0-micros separation. For many neurons tested with a pulse followed by two overlapping echoes, we observed a sensitivity to the coarse delay between the pulse and pair of overlapping echoes and to the separation between the two echoes themselves. The sensitivity to the partial overlap between the two echoes was not tuned to a single temporal separation. For bats, this means that the absolute range to the closest reflector and range between reflectors may be jointly encoded across a small population of single units. There are several possible neuronal mechanisms for encoding the separation between two nearby echoes based on the sensitivity to spectral notches.
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FM 蝙蝠（Myotis lucifugus）听觉皮层延迟敏感神经元的频率组织。
影响因子：
2.5
作者：
Paschal,WG;Wong,D
通讯作者：
Wong,D
DOI：
10.1121/1.416073
发表时间：
1996-09
期刊：
The Journal of the Acoustical Society of America
影响因子：
--
作者：
J. Wotton;T. Haresign;M. Ferragamo;J. Simmons
通讯作者：
J. Wotton;T. Haresign;M. Ferragamo;J. Simmons
影响因子：
2.4
作者：
SAILLANT, PA;SIMMONS, JA;DEAR, SP
通讯作者：
DEAR, SP
回声定位蝙蝠 Eptesicus fuscus 的杂波干扰和回声积分时间。
DOI：
10.1121/1.398693
发表时间：
1989
期刊：
The Journal of the Acoustical Society of America
影响因子：
--
作者：
Simmons,JA;Freedman,EG;Stevenson,SB;Chen,L;Wohlgenant,TJ
通讯作者：
Wohlgenant,TJ
影响因子：
2.5
作者：
Brosch, M;Schreiner, CE
通讯作者：
Schreiner, CE