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D. Shepherd G. Kämper R. K. Murphey 《Journal of comparative physiology. A, Neuroethology, sensory, neural, and behavioral physiology》1988,162(1):1-11
Summary The regional distribution of cerebral glucose utilization, revealed by the14C-2DG technique, was compared between (i) toads after stimulus-specific long-term habituation of the orienting response toward a repeatedly presented prey dummy (habituation group) and (ii) non-habituated toads, readily orienting toward the repetitively presented prey stimulus (naive group). In the habituation group, the ventral medial pallium (vMP), a certain portion of the preoptic area (PO), and the dorsal hypothalamus (dHYP) showed a statistically significantincrease in14C-2DG-uptake;decrease was observed in the ventral layers of the optic tectum (vOT), a portion of the tegmental reticular formation (RET), the ventral cerebellum (vCB), and the striatum (STR). The results suggest that stimulus-specific long-term habituation of prey-catching affects both, components of thestimulus-response mediating circuit (e.g., involving OT), and structures extrinsic to it, (e.g., vMP, PO, dHYP), which may belong to amodulatory circuitry. Bilateral lesions to vMP strongly delay habituation. Our results are suggesting that damping of the adequate behavioral motor response during habituation involves active inhibitory processes of a modulatory system that develops in strength during stimulus repetition so as to suppress response output, which basically supports Sokolov's hypothesis (1975).Abbreviations
A
anterior dorsal thalamic nucleus
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AL
amygdala, lateral portion
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dCB
dorsal half of the cerebellum
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vCB
ventral half of the cerebellum
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DP
dorsal pallium
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dHYP
dorsal hypothalamus
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pLP
posterior half of the lateral pallium
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Lpd
lateral postero-dorsal thalamus
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Lpv
lateral postero-ventral thalamus
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aMP
anterior third of the medial pallium
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dMP
dorsal portion of the posterior medial pallium
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vMP
ventral two-third of the posterior medial pallium
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MS
medial septum
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dOT
dorsal layers of the optic tectum
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vOT
ventral layers of the optic tectum
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P
posterior thalamic nucleus
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PO
preoptic area
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RET
tegmental portion of the medial reticular formation
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STR
striatum, dorsal and ventral portion
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vTEG
ventral tegmentum 相似文献
3.
The cercal sensory system of the cricket is being examined using anatomical, physiological, and computer simulation techniques in order to better understand the assembly of sensory systems. This particular sensory system is of interest because it functions like numerically more complex vertebrate sensory systems but offers, to the neuroscientist, the technical advantages of a small number of large identified neurons. Two aspects of sensory processing are being examined in this system; the spatial aspects of a stimulus that tell an animal where a target is in its environment, and the qualities of a stimulus that help the animal to identify the stimulus. The spatial aspects of a stimulus are analyzed by a topographic mapping of the animal's sensory environment. The feature extraction machinery for other aspects of the stimulus lacks any obvious anatomical order and is embedded within the topographic map. We are attempting to tease apart the genetic and the epigenetic components of the assembly process for this sensory system. Here we review our progress with emphasis on the epigenetic aspects of its assembly. We describe previously published work on plasticity as well as new experiments focussed on the role of neuronal activity in the assembly of this neural circuit. Finally, we briefly describe simulation experiments that are helping us understand the role of various forms of synaptic plasticity in the determination of receptive fields. 相似文献
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Anatomy and physiology of identified wind-sensitive local interneurons in the cricket cercal sensory system 总被引:1,自引:0,他引:1
Deana A. Bodnar John P. Miller Gwen A. Jacobs 《Journal of comparative physiology. A, Neuroethology, sensory, neural, and behavioral physiology》1991,168(5):553-564
1. A group of wind sensitive local interneurons (9DL Interneurons) in the terminal abdominal ganglion of the cricket Acheta domesticus were identified and studied using intracellular staining and recording techniques. 2. The 9DL interneurons had apparent resting potentials ranging from -38 mV to -45 mV. At this membrane potential, these cells produced graded responses to wind stimuli; action potentials were never observed at these resting potentials. However, when the 9DL interneurons were hyperpolarized to a membrane potential of approximately -60 mV, a single action potential at the leading edge of the wind stimulus response was sometimes observed. 3. The wind stimulus threshold of the 9DL interneurons to the types of stimuli used in these studies was approximately 0.01 cm/s. Above this threshold, the excitatory responses increased logarithmically with increasing peak wind velocity up to approximately 0.5 cm/s. 4. The 9DL interneurons were directionally sensitive; their response amplitudes varied with wind stimulus orientation. 9DL1 cells responded maximally when stimulated with wind directed at the front of the animal. The apparent peak in directional sensitivity of the 9DL2 interneurons varied between the side and the rear of the animal, depending upon the site of electrode penetration within the cell's dendritic arbor. 5. The locations of dendritic branches of the 9DL interneurons within the afferent map of wind direction were used to predict the excitatory receptive field of these interneurons. 相似文献
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V. Y. Vedenina G. I. Rozhkova A. K. Panjutin A. L. Byzov G. Kämper 《Journal of comparative physiology. A, Neuroethology, sensory, neural, and behavioral physiology》1998,183(5):553-561
Three identified interneurons of the cercal system were investigated electrophysiologically; these interneurons are sensitive
only to stimulation of cercal filiform-hair sensilla by low-frequency sound. Measurement of the frequency ranges revealed
cut-off frequencies between ca. 20 and 70 Hz. Analysis of the responses near threshold and at higher intensities in the frequency
range 5–500 Hz shows that one of them (Interneuron 9-1b) exhibits a sensitivity maximum at the frequency-intensity combination
necessary for the perception of an intraspecific signal at 30 Hz. This band-pass behavior disappears at higher stimulus intensities.
In order to investigate the mechanism of the low-frequency selectivity of the interneurons, two-tone stimulation experiments
were performed. When stimuli in the best-frequency range were superimposed by a 100-Hz tone, the spiking activity was suppressed
in an intensity-dependent manner.
Accepted: 22 July 1998 相似文献
8.
G. I. Rozhkova V. Y. Vedenina G. Kämper 《Journal of comparative physiology. A, Neuroethology, sensory, neural, and behavioral physiology》1999,184(2):161-167
The bilateral pairs of cercal interneurons 10-2a and 10-3a in the cricket terminal ganglion are supposed to constitute a
functional system for measuring the direction of air-borne signals, based on their phase-locked responses and selective directional
sensitivity. The purpose of this study was to obtain information on the frequency and intensity characteristics and thus the
potential working range of this system. By recording intracellularly from the axons of the interneurons we measured responses
for stimuli of varying frequency, intensity, and direction. Typically, the stimulus frequency range examined extended from
5 to 600 Hz, at intensities of 0.03–30 mm s−1 (peak-to-peak air-particle velocity). The results show that interneurons 10-2a and 10-3a preserved their level of activity,
response type, and direction tuning in the whole frequency range tested. Stimulus-response cross-correlograms revealed that
spike trains were synchronized with stimulus waves at even higher frequencies, at least up to 1000 Hz. At a given air-particle
velocity in the range of about 2–2.5 logarithmic units, the spike number responses of the interneurons were nearly constant
over a wide frequency range. Directional diagrams appeared to be independent of stimulus frequency, both in orientation and
in amplitude.
Accepted: 14 October 1998 相似文献
9.
D. A. Bodnar 《Journal of comparative physiology. A, Neuroethology, sensory, neural, and behavioral physiology》1993,172(5):641-651
This study examined the effects of a set of identified wind-sensitive local interneurons (9DL interneurons) on the wind-evoked spike output and directional sensitivity of an ascending interneuron (10-3) in the cricket (Acheta domesticus) cercal sensory system. Comparison of the directional sensitivities of the 9DL interneurons and 10-3 revealed that 3 of the 9DL interneurons have a large degree of overlap in their excitatory receptive fields with that of 10-3. Photoinactivation of any one of these 3 9DL interneurons resulted in a significant decrease in the spike output of 10-3 at its optimal excitatory wind stimulus positions. However, the overall directional sensitivity of 10-3 remained essentially unchanged. Photoinactivation of the one 9DL interneuron which had no overlap in its excitatory receptive field with 10-3 did not affect 10-3's responsiveness to wind stimuli. Results from simultaneous intracellular recordings of 10-3 and one of the 9DL interneurons which had an excitatory influence on 10-3 showed that depolarization of the local interneuron produced an epsp in 10-3, and could elicit several action potentials. Comparison of the morphologies of the 9DL interneurons and 10-3 revealed that the 3 9DL interneurons which had an excitatory influence on 10-3 all had regions of dendritic overlap with this ascending interneuron.Abbreviations ANOVA
analysis of variance
- Contra
contralateral
- epsp
excitatory post-synaptic potential
- Ipsi
ipsilateral
- LGI
lateral giant interneuron
- MGI
medial giant interneuron 相似文献
10.
The cercal sensory system of the cricket mediates the detection and analysis of low velocity air currents in the animal's immediate environment, and is implemented around an internal representation of air current direction that demonstrates the essential features of a continuous neural map. Previous neurophysiological and anatomical studies have yielded predictions of the global spatio-temporal patterns of activity that should be evoked in the sensory afferent map by air current stimuli of different directions. We tested those predictions by direct visualization of ensemble afferent activity patterns using Ca2+ -sensitive indicators. The AM ester of the fluorescent Ca2+ indicator (Oregon Green 488 BAPTA-1 AM) was injected under the sheath of a cercal sensory nerve containing all of the mechanosensory afferent axons from one cercus. Optical signals were recorded with a digital intensified CCD camera. Control experiments using direct electrical stimulation of stained and unstained nerves demonstrated that the observed Ca2+ signals within the terminal abdominal ganglion (TAG) were due to activation of the dye-loaded sensory afferent neurons. To visualize the spatial patterns of air-current-evoked ensemble activity, unidirectional air currents were applied repeatedly from eight different directions, and the optically recorded responses from each direction were averaged. The dispersion of the optical signals by the ganglion limited the spatial resolution with which these ensemble afferent activity patterns could be observed. However, resolution was adequate to demonstrate that different directional stimuli induced different spatial patterns of Ca2+ elevation in the terminal arbors of afferents within the TAG. These coarsely- resolved, optically-recorded patterns were consistent with the anatomy-based predictions. 相似文献
11.
T. Kumagai T. Shimozawa Y. Baba 《Journal of comparative physiology. A, Neuroethology, sensory, neural, and behavioral physiology》1998,183(1):7-21
The deflection sensitivities of cercal filiform hairs of the cricket, Gryllus bimaculatus, were determined by direct measurement. The tangential velocity of deflecting hair shafts in response to stimulus air motion
was measured in situ by a laser-Doppler velocimeter with surface scattering of the shaft. The velocity of the stimulus air motion in a small wind
tunnel was calibrated by the same velocimeter with smoke from a joss-stick. The mobility of the hair was obtained from former
measurements with reference to the latter calibration of the single apparatus. A Gaussian white noise signal was employed
as a stimulus waveform, and the stimulus-response transfer function was calculated through a cross-correlation method, which
provides greater precision and wider frequency for a longer period of measurement. The mobility of hair was expressed in deflection
amplitudes and phase shifts in reference to the velocity sinusoid of a stimulus at various frequencies. The measurements established
the following conclusions. The wind receptor hairs comprise an array of mechanical band-pass filters whose best frequencies
are inversely proportional to the length. The motion dynamics of the wind-receptor hairs have strong damping.
Accepted: 24 February 1998 相似文献
12.
Structural scaling and functional design of the cercal wind-receptor hairs of cricket 总被引:1,自引:0,他引:1
T. Shimozawa T. Kumagai Y. Baba 《Journal of comparative physiology. A, Neuroethology, sensory, neural, and behavioral physiology》1998,183(2):171-186
We have estimated the intrinsic mechanical parameters of cricket cercal wind-receptor hairs. The hairs were modeled as an
inverted pendulum, and mechanical parameters of the equation of motion were determined from data given by a systematic measurement
of mobility by the least-square error method. The theoretical torque which turns the hair shaft is given by the drag force
due to the moving air. The drag force is given by the method of Stokes' mechanical impedance of an oscillating cylinder in
viscous fluid. The effect of the boundary layer in which air is stagnating on the substrate surface is also taken into account.
The moment of inertia of a hair shaft shows a clear length dependency to the power of 4.32 of the hair length. The torsional
resistance within the hair base and the stiffness of hair-supporting spring also show clear length dependencies to the power
of 2.77 and 1.67, respectively. The torsional resistance within the hair base is so large that the hair is a strongly damped
non-oscillatory second-order system. The large resistance within the hair base represents an efficient energy absorption by
the sensory cell. The resistance seems to match with the source impedance, i.e., the frictional resistance at the site of
air-hair contact. The impedance matching provides the condition of maximum power transmission from the moving air to the sensory
cell. Structural scaling is discussed in relation to the functional scaling of the frequency-range fractionation of the mechanical
filter array with a common biological design.
Accepted: 24 February 1998 相似文献
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G. Kämper V. Y. Vedenina 《Journal of comparative physiology. A, Neuroethology, sensory, neural, and behavioral physiology》1998,182(6):715-724
Interneurons in the cercal sensory system of crickets respond in a cell-specific manner if the cercal hair sensilla are stimulated
by air-particle oscillations at frequencies below about 2000 Hz. We investigated the filter properties of several of these
interneurons, and tested the effect of stimulus intensity (typically 0.3–50 mm s−1 peak-to-peak air-particle velocity) on the frequency response in the range 5–600 Hz. We focus on three interneurons (the
lateral and medial giant interneurons and interneuron 9-3a) of Acheta domesticus which are characterized by a relatively high sensitivity above ca. 50–200 Hz. The responses of the medial giant interneuron
usually increase monotonically with frequency and intensity. Interneuron 9-3a and the lateral giant interneuron exhibit saturation
or response decrement at high frequencies and intensities. The lateral giant interneuron has an additional peak of sensitivity
below about 40 Hz. Small individual variations in the relative locations of the two response areas of this interneuron within
the frequency-intensity field are responsible for a large variability obtained if frequency-response curves are determined
for particular intensities. Stimulus frequency does not affect the principal directional preferences of the three interneurons.
Nevertheless, if tested individually, the lateral giant interneuron and interneuron 9-3a exhibit small changes of directional
tuning.
Accepted: 12 November 1997 相似文献
14.
Masamichi Kanou Taisuke Osawa Tateo Shimozawa 《Journal of comparative physiology. A, Neuroethology, sensory, neural, and behavioral physiology》1988,162(5):573-579
1. | The ecdysial growth of cercal filiform hairs was investigated in the cricketGryllus bimaculatus. The length of hairs varied from 40 to 500 m in the 1st, from 40 to 650 m in the 3rd and from 30 to 800 m in the 5th instar nymphs (Fig. 1). Hemimetabolous development causes both hair growth and the appearance of new hairs at each ecdysis (Figs. 2, 3). The newly acquired hairs were shorter than 200 m in every case (Fig. 4). |
2. | Velocity thresholds of cercal sensory interneurons (CSIs) to sinusoidal air-currents were measured in 3rd instar nymphs (Fig. 5 A, B, C). CSIs 8-1 (medial giant interneuron: MGI) and 9-1 (lateral giant interneuron: LGI) showed threshold curves of acceleration sensitivity similar to those in adults. The thresholds for CSIs 8-1 and 9-1 were on the average higher in nymphs than in adults. The threshold curves for the two velocity-sensitive CSIs 10-2 and 10-3 were similar for nymphs and adults. |
3. | Velocity thresholds of cercal filiform sensilla were measured in 3rd instar nymphs (Fig. 6). In spite of the small size of nymphal hairs, the most sensitive ones showed the same sensitivity as did the long 1000 m hairs of the adult. |
4. | The filiform hairs in 3rd instar nymphs were supported by a weaker spring than in adults (Fig. 7). Relative stiffness was about 50% of that in the long hairs in adults, but not much different than that in the short hairs. |
5. | Based on a theoretical estimation of hair motion, the threshold angle of a filiform sensillum in the 3rd instar nymph was calculated (Fig. 9). Threshold angles of the long sensilla seemed to be unchanged throughout hemimetabolous development. |
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The rearing condition necessary for behavioral compensation after sensory deprivation was investigated in the cricket Gryllus bimaculatus. The right-cercus-ablated cricket was reared in a glass vial with a slightly larger diameter than the body length of the cricket. After two weeks of rearing in the vial, the air-puff-evoked escape behavior of the cricket was investigated. The response rate (relative occurrence of the escape behavior after a standard air puff) obtained was identical with that of crickets reared in a large cage. On the other hand, unlike crickets reared in a large cage, the distorted escape directional property of the cricket reared in the vial was not compensated at all. Control experiments proved that the restraint in the vial did not affect the motor system, and the air motion from environments was not essential for the compensational recovery of the escape direction. Therefore, the ablated crickets required spontaneous walking in order to compensate the directionality of their escape. A self-generated wind caused by spontaneous walking appears necessary for the crickets to realize the defect of their sensory system and to compensate the related escape behavior. A hypothesis for the compensation mechanism based on the efference copy signal is proposed. 相似文献
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The role of the cerci in the spermatophore transfer behavior of the cricket Acheta domesticus was examined. During transfer, the male cerci were held close to the female abdomen where they produced small flicking movements. Male cercal ablation significantly decreased mating success by reducing both the ability of the male to hook the epiphallus on to the female subgenital plate and to transfer the spermatophore. During spermatophore transfer, the male must thread the spermatophore tube into the female genital papilla and attach the spermatophore, via its attachment plate, to the base of the ovipositor. Extracellular recordings from the male genital nerve revealed that a centrally driven, rhythmic bursting activity of genital efferents produced the rhythmic contractions of the five pairs of genital muscles responsible for spermatophore threading. Tactile stimulation of campaniform sensilla on the medial aspect of each cercus inhibited the activity of those motor units responsible for advancing the spermatophore tube during threading, while simultaneously activating the motor units responsible for adjusting the position of the epiphallus. We conclude that mechanosensory neurons on the cerci of the male cricket supply important information on female position to the motor program responsible for spermatophore threading and transfer. 相似文献
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A N Kniazev 《Zhurnal evoliutsionno? biokhimii i fiziologii》1978,14(1):93-95
Naked tungsten microelectrodes were introduced through the chitinous wall close to the cell body of the receptor cells of trichoid hair sensillae, and responses to airpuffs, and rectangular, and trapezoidal displacements of the hair were recorded. Receptors of dorsal zone are activated during lateral deflection, those of ventral zone--during medial deflection and receptors of medial and lateral zones--during deflection to the cercal base. Sensitivity of receptors to the air-puffs is a function of hair length, the largest hairs being most sensitive. During trapezoidal displacement of the hair with different velocities of the slope, discharge frequency of the dynamic response is a function of velocity and angle in the range of angles up to 3-5 degrees (fig. 1). Discharge frequency of the stationary phase (corresponding to the plateau of the stimulus) is mainly a function of velocity in the range up to 6 degrees (fig. 2). The presence of sensillae with different hair length, and hence sensitivity, and definite directionality of receptors in different hair length, and hence sensitivity, and definite directionality of receptors in different zones may provide a basis for amplitude, velocity and direction discrimination of air-puffs or low-frequency mechanical stimulation by the cercal system of crickets. 相似文献