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A E Sauer - One of the best experts on this subject based on the ideXlab platform.
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sensorimotor pathways processing vibratory signals from the femoral Chordotonal Organ of the stick insect
Journal of Comparative Physiology A-neuroethology Sensory Neural and Behavioral Physiology, 1999Co-Authors: A E Sauer, Wolfgang SteinAbstract:The femoral Chordotonal Organ of stick insects senses position and velocity of movements in the femur-tibia joint, as well as tibial vibration. While sensory information about large-scale tibial movements is processed by a well-known neuronal network and elicits resistance reflexes in extensor and flexor tibiae motoneurons, it is not yet known how sensory information about vibration of the tibia is processed. We investigated the transmission of vibration stimuli to tibial extensor motoneurons and their premotor interneurons. Vibration stimuli applied to the femoral Chordotonal Organ evoked responses in tibial extensor and flexor muscles. During ongoing vibration this response adapted rapidly. This adaptation had no effect on the motoneuronal response to large-scale tibial movements. Recording from premotor interneurons revealed that vibratory signals were processed in part by the same interneuronal pathways as (large-scale) velocity and position information. While only certain parts of the interneuronal reflex pathways showed little or no response during vibration stimuli, most neurons responded to both position or velocity stimuli and vibration at the femoral Chordotonal Organ. We conclude that sensory information about vibration of the tibia shares part of the interneuronal pathways that transmit sensory information about large-scale tibial movements to the motoneurons.
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physiology of vibration sensitive afferents in the femoral Chordotonal Organ of the stick insect
Journal of Comparative Physiology A-neuroethology Sensory Neural and Behavioral Physiology, 1999Co-Authors: Wolfgang Stein, A E SauerAbstract:The femoral Chordotonal Organ in orthopterans signals proprioceptive sensory information concerning the femur-tibia joint to the central nervous system. In the stick insect, 80 out of 500 afferents sense tibial position, velocity, or acceleration. It has been assumed that the other sensory cells in the Chordotonal Organ would serve as vibration detectors. Extracellular recordings from the femoral Chordotonal Organ nerve in fact revealed a sensitivity of the sense Organ for vibrations with frequencies ranging from 10 Hz to 4 kHz, with a maximum sensitivity between 200 and 800 Hz. Single vibration-sensitive afferents responded to the same range of frequencies. Their spike activity depended on acceleration amplitude and displacement amplitude of the vibration stimulus. Additionally, 80% of the vibration-sensitive afferents received indirect presynaptic inputs from themselves or from other afferents of the femoral Chordotonal Organ, the amplitude of which depended on stimulus frequency and displacement amplitude. They were associated with a decrease of input resistance in the afferent terminal. From the present investigation we conclude that the femoral Chordotonal Organ of the stick insect is a bifunctional sensory Organ that, on the one hand, measures position and movement of the tibia and, on the other hand, detects vibration of the tibia.
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physiology and vibration sensitive afferents in the femoral Chordotonal Organ of the stick insect a neuroethology sensory neural and behavioral physiology
Journal of Comparative Physiology A-neuroethology Sensory Neural and Behavioral Physiology, 1999Co-Authors: Wolfgang Stein, A E SauerAbstract:The femoral Chordotonal Organ in orthopterans signals proprioceptive sensory information concerning the femur-tibia joint to the central nervous system. In the stick insect, 80 out of 500 afferents sense tibial position, velocity, or acceleration. It has been assumed that the other sensory cells in the Chordotonal Organ would serve as vibration detectors. Extracellular recordings from the femoral Chordotonal Organ nerve in fact revealed a sensitivity of the sense Organ for vibrations with frequencies ranging from 10 Hz to 4 kHz, with a maximum sensitivity between 200 and 800 Hz. Single vibration-sensitive afferents responded to the same range of frequencies. Their spike activity depended on acceleration amplitude and displacement amplitude of the vibration stimulus. Additionally, 80% of the vibration-sensitive afferents received indirect presynaptic inputs from themselves or from other afferents of the femoral Chordotonal Organ, the amplitude of which depended on stimulus frequency and displacement amplitude. They were associated with a decrease of input resistance in the afferent terminal. From the present investigation we conclude that the femoral Chordotonal Organ of the stick insect is a bifunctional sensory Organ that, on the one hand, measures position and movement of the tibia and, on the other hand, detects vibration of the tibia.
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sensorimotor pathways processing vibratory signals from the femoral Chordotonal Organ of the stick insect a neuroethology sensory neural and behavioral physiology
Journal of Comparative Physiology A-neuroethology Sensory Neural and Behavioral Physiology, 1999Co-Authors: A E Sauer, Wolfgang SteinAbstract:The femoral Chordotonal Organ of stick insects senses position and velocity of movements in the femur-tibia joint, as well as tibial vibration. While sensory information about large-scale tibial movements is processed by a well-known neuronal network and elicits resistance reflexes in extensor and flexor tibiae motoneurons, it is not yet known how sensory information about vibration of the tibia is processed. We investigated the transmission of vibration stimuli to tibial extensor motoneurons and their premotor interneurons. Vibration stimuli applied to the femoral Chordotonal Organ evoked responses in tibial extensor and flexor muscles. During ongoing vibration this response adapted rapidly. This adaptation had no effect on the motoneuronal response to large-scale tibial movements. Recording from premotor interneurons revealed that vibratory signals were processed in part by the same interneuronal pathways as (large-scale) velocity and position information. While only certain parts of the interneuronal reflex pathways showed little or no response during vibration stimuli, most neurons responded to both position or velocity stimuli and vibration at the femoral Chordotonal Organ. We conclude that sensory information about vibration of the tibia shares part of the interneuronal pathways that transmit sensory information about large-scale tibial movements to the motoneurons.
Wolfgang Stein - One of the best experts on this subject based on the ideXlab platform.
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sensorimotor pathways processing vibratory signals from the femoral Chordotonal Organ of the stick insect
Journal of Comparative Physiology A-neuroethology Sensory Neural and Behavioral Physiology, 1999Co-Authors: A E Sauer, Wolfgang SteinAbstract:The femoral Chordotonal Organ of stick insects senses position and velocity of movements in the femur-tibia joint, as well as tibial vibration. While sensory information about large-scale tibial movements is processed by a well-known neuronal network and elicits resistance reflexes in extensor and flexor tibiae motoneurons, it is not yet known how sensory information about vibration of the tibia is processed. We investigated the transmission of vibration stimuli to tibial extensor motoneurons and their premotor interneurons. Vibration stimuli applied to the femoral Chordotonal Organ evoked responses in tibial extensor and flexor muscles. During ongoing vibration this response adapted rapidly. This adaptation had no effect on the motoneuronal response to large-scale tibial movements. Recording from premotor interneurons revealed that vibratory signals were processed in part by the same interneuronal pathways as (large-scale) velocity and position information. While only certain parts of the interneuronal reflex pathways showed little or no response during vibration stimuli, most neurons responded to both position or velocity stimuli and vibration at the femoral Chordotonal Organ. We conclude that sensory information about vibration of the tibia shares part of the interneuronal pathways that transmit sensory information about large-scale tibial movements to the motoneurons.
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physiology of vibration sensitive afferents in the femoral Chordotonal Organ of the stick insect
Journal of Comparative Physiology A-neuroethology Sensory Neural and Behavioral Physiology, 1999Co-Authors: Wolfgang Stein, A E SauerAbstract:The femoral Chordotonal Organ in orthopterans signals proprioceptive sensory information concerning the femur-tibia joint to the central nervous system. In the stick insect, 80 out of 500 afferents sense tibial position, velocity, or acceleration. It has been assumed that the other sensory cells in the Chordotonal Organ would serve as vibration detectors. Extracellular recordings from the femoral Chordotonal Organ nerve in fact revealed a sensitivity of the sense Organ for vibrations with frequencies ranging from 10 Hz to 4 kHz, with a maximum sensitivity between 200 and 800 Hz. Single vibration-sensitive afferents responded to the same range of frequencies. Their spike activity depended on acceleration amplitude and displacement amplitude of the vibration stimulus. Additionally, 80% of the vibration-sensitive afferents received indirect presynaptic inputs from themselves or from other afferents of the femoral Chordotonal Organ, the amplitude of which depended on stimulus frequency and displacement amplitude. They were associated with a decrease of input resistance in the afferent terminal. From the present investigation we conclude that the femoral Chordotonal Organ of the stick insect is a bifunctional sensory Organ that, on the one hand, measures position and movement of the tibia and, on the other hand, detects vibration of the tibia.
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physiology and vibration sensitive afferents in the femoral Chordotonal Organ of the stick insect a neuroethology sensory neural and behavioral physiology
Journal of Comparative Physiology A-neuroethology Sensory Neural and Behavioral Physiology, 1999Co-Authors: Wolfgang Stein, A E SauerAbstract:The femoral Chordotonal Organ in orthopterans signals proprioceptive sensory information concerning the femur-tibia joint to the central nervous system. In the stick insect, 80 out of 500 afferents sense tibial position, velocity, or acceleration. It has been assumed that the other sensory cells in the Chordotonal Organ would serve as vibration detectors. Extracellular recordings from the femoral Chordotonal Organ nerve in fact revealed a sensitivity of the sense Organ for vibrations with frequencies ranging from 10 Hz to 4 kHz, with a maximum sensitivity between 200 and 800 Hz. Single vibration-sensitive afferents responded to the same range of frequencies. Their spike activity depended on acceleration amplitude and displacement amplitude of the vibration stimulus. Additionally, 80% of the vibration-sensitive afferents received indirect presynaptic inputs from themselves or from other afferents of the femoral Chordotonal Organ, the amplitude of which depended on stimulus frequency and displacement amplitude. They were associated with a decrease of input resistance in the afferent terminal. From the present investigation we conclude that the femoral Chordotonal Organ of the stick insect is a bifunctional sensory Organ that, on the one hand, measures position and movement of the tibia and, on the other hand, detects vibration of the tibia.
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sensorimotor pathways processing vibratory signals from the femoral Chordotonal Organ of the stick insect a neuroethology sensory neural and behavioral physiology
Journal of Comparative Physiology A-neuroethology Sensory Neural and Behavioral Physiology, 1999Co-Authors: A E Sauer, Wolfgang SteinAbstract:The femoral Chordotonal Organ of stick insects senses position and velocity of movements in the femur-tibia joint, as well as tibial vibration. While sensory information about large-scale tibial movements is processed by a well-known neuronal network and elicits resistance reflexes in extensor and flexor tibiae motoneurons, it is not yet known how sensory information about vibration of the tibia is processed. We investigated the transmission of vibration stimuli to tibial extensor motoneurons and their premotor interneurons. Vibration stimuli applied to the femoral Chordotonal Organ evoked responses in tibial extensor and flexor muscles. During ongoing vibration this response adapted rapidly. This adaptation had no effect on the motoneuronal response to large-scale tibial movements. Recording from premotor interneurons revealed that vibratory signals were processed in part by the same interneuronal pathways as (large-scale) velocity and position information. While only certain parts of the interneuronal reflex pathways showed little or no response during vibration stimuli, most neurons responded to both position or velocity stimuli and vibration at the femoral Chordotonal Organ. We conclude that sensory information about vibration of the tibia shares part of the interneuronal pathways that transmit sensory information about large-scale tibial movements to the motoneurons.
Tom Matheson - One of the best experts on this subject based on the ideXlab platform.
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range fractionation in the locust metathoracic femoral Chordotonal Organ
Journal of Comparative Physiology A-neuroethology Sensory Neural and Behavioral Physiology, 1992Co-Authors: Tom MathesonAbstract:Insect femoral Chordotonal Organs are internal proprioceptors which monitor the position and movements of the femur-tibia joint of the leg. The locust (Locusta migratoria) metathoracic femoral Chordotonal Organ is composed of approximately 100 neurones with a variety of response properties. In this study intracellular recordings were used to examine the range fractionation of phasic and tonic responses to tibial movements. Some neurones responded across the full range of leg angles, while others had restricted response ranges, and could therefore act as labeled lines. Neurones with maximal firing at mid-angles are described for the first time in a locust femoral Chordotonal Organ. Responses are discussed in terms of underlying structural constraints on signal transduction.
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morphology of the central projections of physiologically characterised neurones from the locust metathoracic femoral Chordotonal Organ
Journal of Comparative Physiology A-neuroethology Sensory Neural and Behavioral Physiology, 1992Co-Authors: Tom MathesonAbstract:The metathoracic femoral Chordotonal Organ of the locust (Locusta migratoria) is an internal proprioceptor composed of mechanosensory neurones which respond to tibial position, velocity, or acceleration, or to combinations of these parameters. Discriminant function analyses confirmed the visual observation that neurones with different responses to tibial movements had different central branching patterns. Some aspects of the projections were consistent for all neurones (e.g., the path taken by the main neurite through the metathoracic ganglion), whereas other regions of branches were consistently reduced or missing in some response classes. Some position-and-acceleration receptors had no main branches off the main neurite, and must therefore make relatively restricted contact with motor neurones and interneurones. Phasic or tonic neurones which responded in ranges of tibial extension had branches which projected further medial in Dorsal Commissures III and IV than similar neurones which responded in ranges of tibial flexion. I compare my results to previous studies of mapping in the insect CNS.
George Theophilidis - One of the best experts on this subject based on the ideXlab platform.
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dimethylsulfoxide dmso eliminates the response of the sensory neurones of an insect mechanoreceptor the femoral Chordotonal Organ of locusta migratoria but blocks conduction of their sensory axons at much higher concentrations a possible mechanism of analgesia
Neuroscience Letters, 1994Co-Authors: George Theophilidis, K KravariAbstract:The analgesic effects of dimethylsulfoxide (DMSO) on the sensory neurones and the sensory axons of an insect mechanoreceptor, the femoral Chordotonal Organ of Locusta migratoria, were examined. The metathoracic femur was dissected, to expose the Chordotonal Organ and its sensory nerve, in a chamber containing oxygenated physiological solution where the DMSO was gradually added. The tibia movement was used for the mechanical stimulation of the Chordotonal Organ while neural activity was recorded and measured using standard electrophysiological methods. For the Chordotonal Organ, the blocking concentration of DMSO, the concentration which eliminates the response of the sensory neurones to mechanical stimulation by 50% in 18-20 min, was estimated to be 0.85 +/- 0.11% (n = 6) v/v. On the contrary, the blocking concentration of the DMSO for the sensory axons was 4.6 +/- 0.7% (n = 6) v/v, approximately five times higher than the concentration required to inactivate the sensory neurones. The implications of this difference in the physiological mechanisms involved for the DMSO-induced analgesia are discussed.
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the neurophysiological effects of deltamethrin and fluvalinate on an insect mechanoreceptor the metathoracic femoral Chordotonal Organ of locusta migratoria
Pesticide Biochemistry and Physiology, 1993Co-Authors: George Theophilidis, A Pappa, Euphemia PapadopouloumourkidouAbstract:Abstract The effects of deltamethrin and fluvalinate on the response of the metathoracic femoral Chordotonal Organ of Locusta migratoria were investigated using a bath application method. It was found that at low concentrations, for deltamethrin below 4.06 × 10−8M and for fluvalinate below 3.33 × 10−7M, the two insecticides seem to have an effect on the sensory neurons of the femoral Chordotonal Organ. Above these concentrations the two insecticides effect the conduction properties of the sensory axons. The possible effects of these insecticides on the peripheral nervous system of insects are further discussed.
Reinhard Lakesharlan - One of the best experts on this subject based on the ideXlab platform.
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vibrational sensitivity of the subgenual Organ complex in female sipyloidea sipylus stick insects in different experimental paradigms of stimulus direction leg attachment and ablation of a connective tibial sense Organ
Comparative Biochemistry and Physiology A-molecular & Integrative Physiology, 2017Co-Authors: Johannes Straus, Reinhard LakesharlanAbstract:We document the sensitivity to sinusoidal vibrations for Chordotonal Organs in the stick insect tibia (Sipyloidea sipylus). In the tibia, the scolopidial subgenual Organ (~40 scolopidial sensilla), distal Organ (~20 scolopidial sensilla), and distal tibial Chordotonal Organ (~7 scolopidial sensilla) are present. We study the sensitivity of tibial sensory Organs in all leg pairs to vibration stimuli as sensory thresholds by recording summed action potentials from Nervus cruris in the femur. The tibia was stimulated with a minishaker delivering vibrational stimuli. Because different experimental procedures may affect the vibration sensitivity, we here analysed possible effects of different experimental conditions: (1) the stimulus direction delivered in either horizontal or vertical direction to the leg; (2) recording responses only from the subgenual Organ complex after ablation of the distal tibial Chordotonal Organ, and (3) the attachment of the leg to the minishaker by plastilin, beeswax-colophony, or freely standing legs. The tibial scolopidial Organs give summed responses to vibration stimuli with highest sensitivity between 500 and 1000Hz for all leg pairs. In the different experimental series, we find that (1) thresholds were influenced by stimulation direction with lower thresholds in response to vertical vibrations, (2) ablating the distal tibial Chordotonal Organ by cutting the distal-most tibia did not change the summed sensory thresholds significantly, and (3) the attachment material between legs and the minishaker (plastilin or beeswax-colophony mixture) did not significant influence the sensory thresholds against free-standing tarsi. The distal tibial Chordotonal Organ is a connective Chordotonal Organ attached to a tendon and is likely a proprioceptive Organ. These results emphasise that vibrational thresholds are mainly direction-sensitive. Thus, the direction of stimulus delivery during electrophysiological recordings is relevant for comparisons of vibratory sensory thresholds.
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neuroanatomy of the complex tibial Organ in the splay footed cricket comicus calcaris irish 1986 orthoptera ensifera schizodactylidae
The Journal of Comparative Neurology, 2010Co-Authors: Johannes Strauss, Reinhard LakesharlanAbstract:The subgenual Chordotonal Organ complex in insects is modified in ensiferan taxa like Gryllidae and Tettigoniidae into hearing Organs with specific sets of auditory receptors. Here, this sensory Organ complex is documented in the nonhearing splay-footed cricket Comicus calcaris. The tibial Chordotonal Organ consists of three parts: the subgenual Organ, the intermediate Organ, and the crista acustica homolog. The latter is an array of linearly Organized neurons homologous to auditory receptors in the tibial hearing Organs of Tettigoniidae. The tibial Organ is structurally similar in all three leg pairs, with similar neuron numbers in the fore- and midleg, but lower numbers in the hindleg. The foreleg crista acustica homolog consists of 34±4 neurons, the highest number in an atympanate Ensiferan. Additionally, an accessory Chordotonal Organ with 15±5 neurons innervated by nerve 5B1 is present in the foreleg. The central projection of the tibial Organreveals ipsilateral sensory terminals in the primary sensory neuropil, the medial ventral association center with terminations close to the midline. As determined from extracellular recordings, the entire tibial Organ is vibrosensitive. The Organization of the tibial Organ is compared to other ensiferan auditory and nonauditory tibial Organs. Spatial orientation of neurons in the crista acustica homolog is not reminiscent of auditory structures, and the neuroanatomy is discussed with respect to stridulation behavior and the evolutionary origin of hearing in Ensifera.
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morphology and physiology of the prosternal Chordotonal Organ of the sarcophagid fly sarcophaga bullata parker
Journal of Insect Physiology, 2007Co-Authors: Heiko Stölting, Andreas Stumpner, Reinhard LakesharlanAbstract:The anatomy and the physiology of the prosternal Chordotonal Organ (pCO) within the prothorax of Sarcophaga bullata is analysed. Neuroanatomical studies illustrate that the approximately 35 sensory axons terminate within the median ventral association centre of the different neuromeres of the thoracico-abdominal ganglion. At the single-cell level two classes of receptor cells can be discriminated physiologically and morphologically: receptor cells with dorso-lateral branches in the mesothoracic neuromere are insensitive to frequencies below approximately 1 kHz. Receptor cells without such branches respond most sensitive at lower frequencies. Absolute thresholds vary between 0.2 and 8 m/s2 for different frequencies. The sensory information is transmitted to the brain via ascending interneurons. Functional analyses reveal a mechanical transmission of forced head rotations and of foreleg vibrations to the attachment site of the pCO. In summed action potential recordings a physiological correlate was found to stimuli with parameters of leg vibrations, rather than to those of head rotation. The data represent a first physiological study of a putative predecessor Organ of an insect ear.