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Rana A, Emanuel S, Adams ME, Libersat F. Suppression of host nocifensive behavior by parasitoid wasp venom. Front Physiol 2022; 13:907041. [PMID: 36035493 PMCID: PMC9411936 DOI: 10.3389/fphys.2022.907041] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2022] [Accepted: 07/04/2022] [Indexed: 11/15/2022] Open
Abstract
The parasitoid wasp Ampulex compressa envenomates the brain of its host the American cockroach (Periplaneta americana), thereby making it a behaviorally compliant food supply for its offspring. The target of venom injection is a locomotory command center in the brain called the central complex. In this study, we investigate why stung cockroaches do not respond to injuries incurred during the manipulation process by the wasp. In particular, we examine how envenomation compromises nociceptive signaling pathways in the host. Noxious stimuli applied to the cuticle of stung cockroaches fail to evoke escape responses, even though nociceptive interneurons projecting to the brain respond normally. Hence, while nociceptive signals are carried forward to the brain, they fail to trigger robust nocifensive behavior. Electrophysiological recordings from the central complex of stung animals demonstrate decreases in peak firing rate, total firing, and duration of noxious-evoked activity. The single parameter best correlated with altered noxious-evoked behavioral responses of stung cockroaches is reduced duration of the evoked response in the central complex. Our findings demonstrate how the reproductive strategy of a parasitoid wasp is served by venom-mediated elimination of aversive, nocifensive behavior in its host.
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Affiliation(s)
- Amit Rana
- Department of Life Sciences and Zlotowski Center for Neurosciences, Ben Gurion University of the Negev, Be’er Sheva, Israel
| | - Stav Emanuel
- Department of Life Sciences and Zlotowski Center for Neurosciences, Ben Gurion University of the Negev, Be’er Sheva, Israel
| | - Michael E. Adams
- Department of Molecular, Cell, and Systems Biology, University of California, Riverside, Riverside, CA, United States
- Department of Entomology, University of California, Riverside, Riverside, CA, United States
| | - Frederic Libersat
- Department of Life Sciences and Zlotowski Center for Neurosciences, Ben Gurion University of the Negev, Be’er Sheva, Israel
- *Correspondence: Frederic Libersat,
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Emanuel S, Libersat F. Nociceptive Pathway in the Cockroach Periplaneta americana. Front Physiol 2019; 10:1100. [PMID: 31496959 PMCID: PMC6712093 DOI: 10.3389/fphys.2019.01100] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2019] [Accepted: 08/08/2019] [Indexed: 12/31/2022] Open
Abstract
Detecting and avoiding environmental threats such as those with a potential for injury is of crucial importance for an animal’s survival. In this work, we examine the nociceptive pathway in an insect, the cockroach Periplaneta americana, from detection of noxious stimuli to nocifensive behavior. We show that noxious stimuli applied to the cuticle of cockroaches evoke responses in sensory axons that are distinct from tactile sensory axons in the sensory afferent nerve. We also reveal differences in the evoked response of post-synaptic projection interneurons in the nerve cord to tactile versus noxious stimuli. Noxious stimuli are encoded in the cockroach nerve cord by fibers of diameter different from that of tactile and wind sensitive fibers with a slower conduction velocity of 2–3 m/s. Furthermore, recording from the neck-connectives show that the nociceptive information reaches the head ganglia. Removing the head ganglia results in a drastic decrease in the nocifensive response indicating that the head ganglia and the nerve cord are both involved in processing noxious stimuli.
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Affiliation(s)
- Stav Emanuel
- Department of Life Sciences and Zlotowski Center for Neurosciences, Ben Gurion University, Beer Sheva, Israel
| | - Frederic Libersat
- Department of Life Sciences and Zlotowski Center for Neurosciences, Ben Gurion University, Beer Sheva, Israel
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Abstract
In this study, we describe the most ultralightweight living legged robot to date that makes it a strong candidate for a search and rescue mission. The robot is a living beetle with a wireless electronic backpack stimulator mounted on its thorax. Inheriting from the living insect, the robot employs a compliant body made of soft actuators, rigid exoskeletons, and flexure hinges. Such structure would allow the robot to easily adapt to any complex terrain due to the benefit of soft interface, self-balance, and self-adaptation of the insect without any complex controller. The antenna stimulation enables the robot to perform not only left/right turning but also backward walking and even cessation of walking. We were also able to grade the turning and backward walking speeds by changing the stimulation frequency. The power required to drive the robot is low as the power consumption of the antenna stimulation is in the order of hundreds of microwatts. In contrast to the traditional legged robots, this robot is of low cost, easy to construct, simple to control, and has ultralow power consumption.
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Affiliation(s)
- Tat Thang Vo Doan
- School of Mechanical and Aerospace Engineering, Nanyang Technological University , Singapore, Singapore
| | - Melvin Y W Tan
- School of Mechanical and Aerospace Engineering, Nanyang Technological University , Singapore, Singapore
| | - Xuan Hien Bui
- School of Mechanical and Aerospace Engineering, Nanyang Technological University , Singapore, Singapore
| | - Hirotaka Sato
- School of Mechanical and Aerospace Engineering, Nanyang Technological University , Singapore, Singapore
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Erickson JC, Herrera M, Bustamante M, Shingiro A, Bowen T. Effective Stimulus Parameters for Directed Locomotion in Madagascar Hissing Cockroach Biobot. PLoS One 2015; 10:e0134348. [PMID: 26308337 PMCID: PMC4550421 DOI: 10.1371/journal.pone.0134348] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2015] [Accepted: 07/09/2015] [Indexed: 02/04/2023] Open
Abstract
Swarms of insects instrumented with wireless electronic backpacks have previously been proposed for potential use in search and rescue operations. Before deploying such biobot swarms, an effective long-term neural-electric stimulus interface must be established, and the locomotion response to various stimuli quantified. To this end, we studied a variety of pulse types (mono- vs. bipolar; voltage- vs. current-controlled) and shapes (amplitude, frequency, duration) to parameters that are most effective for evoking locomotion along a desired path in the Madagascar hissing cockroach (G. portentosa) in response to antennal and cercal stimulation. We identified bipolar, 2 V, 50 Hz, 0.5 s voltage controlled pulses as being optimal for evoking forward motion and turns in the expected contraversive direction without habituation in ≈50% of test subjects, a substantial increase over ≈10% success rates previously reported. Larger amplitudes for voltage (1–4 V) and current (50–150 μA) pulses generally evoked larger forward walking (15.6–25.6 cm; 3.9–5.6 cm/s) but smaller concomitant turning responses (149 to 80.0 deg; 62.8 to 41.2 deg/s). Thus, the radius of curvature of the initial turn-then-run locomotor response (≈10–25 cm) could be controlled in a graded manner by varying the stimulus amplitude. These findings could be used to help optimize stimulus protocols for swarms of cockroach biobots navigating unknown terrain.
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Affiliation(s)
- Jonathan C. Erickson
- Department of Physics-Engineering, Washington and Lee University, Lexington, Virginia, United States of America
- * E-mail:
| | - María Herrera
- Department of Physics-Engineering, Washington and Lee University, Lexington, Virginia, United States of America
| | - Mauricio Bustamante
- Department of Physics-Engineering, Washington and Lee University, Lexington, Virginia, United States of America
| | - Aristide Shingiro
- Department of Physics-Engineering, Washington and Lee University, Lexington, Virginia, United States of America
| | - Thomas Bowen
- Department of Physics-Engineering, Washington and Lee University, Lexington, Virginia, United States of America
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Jackson CW, Hunt E, Sharkh S, Newland PL. Static electric fields modify the locomotory behaviour of cockroaches. ACTA ACUST UNITED AC 2011; 214:2020-6. [PMID: 21613518 DOI: 10.1242/jeb.053470] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Static electric fields are found throughout the environment and there is growing interest in how electric fields influence insect behaviour. Here we have analysed the locomotory behaviour of cockroaches (Periplaneta americana) in response to static electric fields at levels equal to and above those found in the natural environment. Walking behaviour (including velocity, distance moved, turn angle and time spent walking) were analysed as cockroaches approached an electric field boundary in an open arena, and also when continuously exposed to an electric field. On approaching an electric field boundary, the greater the electric field strength the more likely a cockroach would be to turn away from, or be repulsed by, the electric field. Cockroaches completely exposed to electric fields showed significant changes in locomotion by covering less distance, walking slowly and turning more often. This study highlights the importance of electric fields on the normal locomotory behaviour of insects.
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Affiliation(s)
- Christopher W Jackson
- School of Biological Sciences, Building 85, University of Southampton, Highfield Campus, Southampton SO16 7PX, UK
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Liu YC, Herberholz J. Sensory activation and receptive field organization of the lateral giant escape neurons in crayfish. J Neurophysiol 2010; 104:675-84. [PMID: 20505133 DOI: 10.1152/jn.00391.2010] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Crayfish (Procambarus clarkii) have bilateral pairs of giant interneurons that control rapid escape movements in response to predatory threats. The medial giant neurons (MGs) can be made to fire an action potential by visual or tactile stimuli directed to the front of the animal and this leads to an escape tail-flip that thrusts the animal directly backward. The lateral giant neurons (LGs) can be made to fire an action potential by strong tactile stimuli directed to the rear of the animal, and this produces flexions of the abdomen that propel the crayfish upward and forward. These observations have led to the notion that the receptive fields of the giant neurons are locally restricted and do not overlap with each other. Using extra- and intracellular electrophysiology in whole animal preparations of juvenile crayfish, we found that the receptive fields of the LGs are far more extensive than previously assumed. The LGs receive excitatory inputs from descending interneurons originating in the brain; these interneurons can be activated by stimulation of the antenna II nerve or the protocerebral tract. In our experiments, descending inputs alone could not cause action potentials in the LGs, but when paired with excitatory postsynaptic potentials elicited by stimulation of tail afferents, the inputs summed to yield firing. Thus the LG escape neurons integrate sensory information received through both rostral and caudal receptive fields, and excitatory inputs that are activated rostrally can bring the LGs' membrane potential closer to threshold. This enhances the animal's sensitivity to an approaching predator, a finding that may generalize to other species with similarly organized escape systems.
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Affiliation(s)
- Yen-Chyi Liu
- Department of Psychology, University of Maryland, College Park, Maryland 20742, USA
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Newland PL, Hunt E, Sharkh SM, Hama N, Takahata M, Jackson CW. Static electric field detection and behavioural avoidance in cockroaches. J Exp Biol 2008; 211:3682-90. [DOI: 10.1242/jeb.019901] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
SUMMARYElectric fields are pervasively present in the environment and occur both as a result of man-made activities and through natural occurrence. We have analysed the behaviour of cockroaches to static electric fields and determined the physiological mechanisms that underlie their behavioural responses. The behaviour of animals in response to electric fields was tested using a Y-choice chamber with an electric field generated in one arm of the chamber. Locomotory behaviour and avoidance were affected by the magnitude of the electric fields with up to 85% of individuals avoiding the charged arm when the static electric field at the entrance to the arm was above 8–10 kV m–1. Electric fields were found to cause a deflection of the antennae but when the antennae were surgically ablated, the ability of cockroaches to avoid electric fields was abolished. Fixation of various joints of the antennae indicated that hair plate sensory receptors at the base of the scape were primarily responsible for the detection of electric fields, and when antennal movements about the head–scape joint were prevented cockroaches failed to avoid electric fields. To overcome the technical problem of not being able to carry out electrophysiological analysis in the presence of electric fields, we developed a procedure using magnetic fields combined with the application of iron particles to the antennae to deflect the antennae and analyse the role of thoracic interneurones in signalling this deflection. The avoidance of electric fields in the context of high voltage power lines is discussed.
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Affiliation(s)
- Philip L. Newland
- School of Biological Sciences, Biomedical Science Building, University of Southampton, Bassett Crescent East, Southampton SO16 7PX, UK
| | - Edmund Hunt
- School of Biological Sciences, Biomedical Science Building, University of Southampton, Bassett Crescent East, Southampton SO16 7PX, UK
| | - Suleiman M. Sharkh
- School of Engineering Sciences, University of Southampton, Southampton SO17 1BJ, UK
| | - Noriyuki Hama
- Animal Behavior and Intelligence, Division of Biological Sciences, Graduate School of Science, Hokkaido University, Sapporo 060-0810, Japan
| | - Masakazu Takahata
- Animal Behavior and Intelligence, Division of Biological Sciences, Graduate School of Science, Hokkaido University, Sapporo 060-0810, Japan
| | - Christopher W. Jackson
- School of Biological Sciences, Biomedical Science Building, University of Southampton, Bassett Crescent East, Southampton SO16 7PX, UK
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Libersat F. Wasp uses venom cocktail to manipulate the behavior of its cockroach prey. J Comp Physiol A Neuroethol Sens Neural Behav Physiol 2003; 189:497-508. [PMID: 12898169 DOI: 10.1007/s00359-003-0432-0] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2003] [Revised: 05/16/2003] [Accepted: 05/19/2003] [Indexed: 11/25/2022]
Abstract
The sting of the parasitoid wasp Ampulex compressa is unusual, as it induces a transient paralysis of the front legs followed by grooming behavior and then by a long-term hypokinesia of its cockroach prey. Because the wasp's goal is to provide a living meal for its newborn larva, the behavioral changes in the prey are brought about by manipulating the host behavior in a way beneficial to the wasp and its offspring. To this end, the wasp injects its venom cocktail with two consecutive stings directly into the host's central nervous system. The first sting in the thorax causes a transient front leg paralysis lasting a few minutes. This paralysis is due to the presence of a venom component that induces a postsynaptic block of central cholinergic synaptic transmission. Following the head sting, dopamine identified in the venom appears to induce 30 min of intense grooming. During the long-term hypokinesia that follows the grooming, specific behaviors of the prey are inhibited while others are unaffected. We propose that the venom represses the activity of head ganglia neurons thereby removing the descending excitatory drive to the thoracic neurons.
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Affiliation(s)
- F Libersat
- Department of Life Sciences and Zlotowski Center for Neuroscience, Ben-Gurion University, P.O. Box 653, 84105 Beer-Sheva, Israel.
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Schaefer PL, Ritzmann RE. Descending influences on escape behavior and motor pattern in the cockroach. JOURNAL OF NEUROBIOLOGY 2001; 49:9-28. [PMID: 11536194 DOI: 10.1002/neu.1062] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
The escape behavior of the cockroach is a ballistic behavior with well characterized kinematics. The circuitry known to control the behavior lies in the thoracic ganglia, abdominal ganglia, and abdominal nerve cord. Some evidence suggests inputs may occur from the brain or suboesophageal ganglion. We tested this notion by decapitating cockroaches, removing all descending inputs, and evoking escape responses. The decapitated cockroaches exhibited directionally appropriate escape turns. However, there was a front-to-back gradient of change: the front legs moved little if at all, the middle legs moved in the proper direction but with reduced excursion, and the rear legs moved normally. The same pattern was seen when only inputs from the brain were removed, the suboesophageal ganglion remaining intact and connected to the thoracic ganglia. Electromyogram (EMG) analysis showed that the loss of or reduction in excursion was accompanied by a loss of or reduction in fast motor neuron activity. The loss of fast motor neuron activity was also observed in a reduced preparation in which descending neural signals were reversibly blocked via an isotonic sucrose solution superfusing the neck connectives, indicating that the changes seen were not due to trauma. Our data demonstrate that while the thoracic circuitry is sufficient to produce directional escape, lesion or blockage of the connective affects the excitability of components of the escape circuitry. Because of the rapidity of the escape response, such effects are likely due to the elimination of tonic descending inputs.
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Affiliation(s)
- P L Schaefer
- Department of Biology, Case Western Reserve University, Cleveland, Ohio 44106-7080, USA
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Abstract
Studies of insect identified neurons over the past 25 years have provided some of the very best data on sensorimotor integration; tracing information flow from sensory to motor networks. General principles have emerged that have increased the sophistication with which we now understand both sensory processing and motor control. Two overarching themes have emerged from studies of identified sensory interneurons. First, within a species, there are profound differences in neuronal organization associated with both the sex and the social experience of the individual. Second, single neurons exhibit some surprisingly rich examples of computational sophistication in terms of (a) temporal dynamics (coding superimposed upon circadian and shorter-term rhythms), and also (b) what Kenneth Roeder called "neural parsimony": that optimal information can be encoded, and complex acts of sensorimotor coordination can be mediated, by small ensembles of cells. Insect motor systems have proven to be relatively complex, and so studies of their organization typically have not yielded completely defined circuits as are known from some other invertebrates. However, several important findings have emerged. Analysis of neuronal oscillators for rhythmic behavior have delineated a profound influence of sensory feedback on interneuronal circuits: they are not only modulated by feedback, but may be substantially reconfigured. Additionally, insect motor circuits provide potent examples of neuronal restructuring during an organism's lifetime, as well as insights on how circuits have been modified across evolutionary time. Several areas where future advances seem likely to occur include: molecular genetic analyses, neuroecological syntheses, and neuroinformatics--the use of digital resources to organize databases with information on identified nerve cells and behavior.
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Affiliation(s)
- C M Comer
- Laboratory of Integrative Neuroscience, Department of Biological Sciences, University of Illinois at Chicago, Chicago, IL 60607, USA.
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Ritzmann RE, Pollack AJ. Characterization of tactile-sensitive interneurons in the abdominal ganglia of the cockroach,Periplaneta americana. ACTA ACUST UNITED AC 1998. [DOI: 10.1002/(sici)1097-4695(19980215)34:3<227::aid-neu3>3.0.co;2-4] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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12
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Abstract
Escape responses of cockroaches, Periplaneta americana, can be triggered by wind and mediated by a group of "giant interneurons" that ascend from cercal mechanoreceptors to motor centers. Recently it has been observed that escape also can be triggered by tactile stimulation of the antennae, and it is then independent of the giant interneurons. Here we identify a descending antennal mechanosensory pathway that may account for escape. Cobalt backfills demonstrated that a limited number of cells in the head ganglia have axons that project through all three thoracic ganglia. Comparison with known wind-sensory pathways indicated that wind is not a reliable stimulus for activating descending antennal pathways. However, direct touch stimulation of an antenna reliably evoked short-latency responses in cells with axons in the cervical connectives. Intracellular recording and dye injection revealed members of this pathway, referred to as descending mechanosensory interneurons (DMIs). The two axons of largest diameter in the cervical connectives were found to belong to DMIs, and these large-caliber interneurons were studied in detail. One had a soma in the supraesophageal ganglion, and the other in the subesophageal ganglion. Both had extensive neuritic arborizations at the same level as the soma and axonal arbors in all three thoracic ganglia. Each of these DMIs exhibited short-latency responses to small antennal movements, demonstrated a degree of directional sensitivity, and rapidly conducted impulses to thoracic levels. These cells have properties suggesting that they play a role in a short-latency behavior such as touch-evoked escape.
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Correspondence of escape-turning behavior with activity of descending mechanosensory interneurons in the cockroach, Periplaneta americana. J Neurosci 1996. [PMID: 8795636 DOI: 10.1523/jneurosci.16-18-05844.1996] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Two bilaterally paired mechanosensory neurons that respond to antennal touch stimulation recently have been described in the cockroach Periplaneta americana. Here chronic recordings were used to describe the activity of these interneurons in relation to behavior. Parallel intra/extracellular recording experiments showed that both pairs of previously identified descending mechanosensory interneurons (DMIs) were activated after touch stimulation of the antennae and before initiation of escape. On a trial-by-trial basis, the bilateral pattern of their activity was correlated with sensory input and behavior: when one antenna was touched, the contralateral DMI axons displayed impulses earlier and in greater numbers than their ipsilateral homologs; turns were made toward the side with greater DMI activity, i.e., away from the touched antenna. One parameter of DMI activity (the bilateral difference in number of DMI impulses) was correlated with the angular amplitude of turning. In the absence of touch stimulation, unilateral electrical stimulation of a cervical connective via the chronic electrodes produced turning movements similar to natural escape turning and of appropriate directionality. These results support the hypothesis that neural activity in DMIs is involved in the control of antennal touch-evoked escape, and they provide a basis for a model of DMI specification of the direction of escape turning.
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Pollack AJ, Ritzmann RE, Watson JT. Dual pathways for tactile sensory information to thoracic interneurons in the cockroach. JOURNAL OF NEUROBIOLOGY 1995; 26:33-46. [PMID: 7714524 DOI: 10.1002/neu.480260104] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
The escape system of the American cockroach is both fast and directional. In response to wind stimulation both of these characteristics are largely due to the properties of the ventral giant interneurons (vGIs), which conduct sensory information from the cerci on the rear of the animal to type A thoracic interneurons (TIAs) in the thoracic ganglia. The cockroach also escapes from tactile stimuli, and although vGIs are not involved in tactile-mediated escapes, the same thoracic interneurons process tactile sensory information. The response of TIAs to tactile information is typically biphasic. A rapid initial depolarization is followed by a longer latency depolarization that encodes most if not all of the directional information in the tactile stimulus. We report here that the biphasic response of TIAs to tactile stimulation is caused by two separate conducting pathways from the point of stimulation to the thoracic ganglia. Phase 1 is generated by mechanical conduction along the animal's body cuticle or other physical structures. It cannot be eliminated by complete lesion of the nerve cord, and it is not evoked in response to electrical stimulation of abdominal nerves that contain the axons of sensory receptors in abdominal segments. However, it can be eliminated by lesioning the abdominal nerve cord and nerve 7 of the metathoracic ganglion together, suggesting that the relevant sensory structures send axons in nerve 7 and abdominal nerves of anterior abdominal ganglia. Phase 2 of the TIA tactile response is generated by a typical neural pathway that includes mechanoreceptors in each abdominal segment, which project to interneurons with axons in either abdominal connective. Those interneurons with inputs from receptors that are ipsilateral to their axon have a greater influence on TIAs than those that receive inputs from the contralateral side. The phase 1 response has an important role in reducing initiation time for the escape response. Animals in which the phase 2 pathway has been eliminated by lesion of the abdominal nerve cord are still capable of generating a partial startle response with a typically short latency even when stimulated posterior to the lesion.
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Affiliation(s)
- A J Pollack
- Department of Biology, Case Western Reserve University, Cleveland, Ohio 44106-7080
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