1
|
Zhang X, Hedwig B. Sound processing in the cricket brain: evidence for a pulse duration filter. J Neurophysiol 2023; 130:953-966. [PMID: 37701942 PMCID: PMC10649838 DOI: 10.1152/jn.00252.2023] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2023] [Revised: 08/28/2023] [Accepted: 08/28/2023] [Indexed: 09/14/2023] Open
Abstract
The auditory system of female crickets allows them to specifically recognize and approach the species-specific male calling song, defined by sound pulses and silent intervals. Auditory brain neurons form a delay-line and coincidence detector network tuned to the pulse period of the male song. We analyzed the impact of changes in pulse duration on the behavior and the responses of the auditory neurons and the network. We confirm that the ascending neuron AN1 and the local neuron LN2 copy the temporal structure of the song. During ongoing long sound pulses, the delay-line neuron LN5 shows additional rebound responses and the coincidence detector neuron LN3 can generate additional bursts of activity, indicating that these may be driven by intrinsic oscillations of the network. Moreover, the response of the feature detector neuron LN4 is shaped by a combination of inhibitory and excitatory synaptic inputs, and LN4 responds even to long sound pulses with a short depolarization and burst of spikes, like to a sound pulse of natural duration. This response property of LN4 indicates a selective auditory pulse duration filter mechanism of the pattern recognition network, which is tuned to the duration of natural pulses. Comparing the tuning of the phonotactic behavior with the tuning of the local auditory brain neurons to the same test patterns, we find no evidence that a modulation of the phonotactic behavior is reflected at the level of the feature detector neurons. This rather suggests that steering to nonattractive pulse patterns is organized at the thoracic level.NEW & NOTEWORTHY Pulse period selectivity has been reported for the cricket delay-line and coincidence detector network, whereas pulse duration selectivity is evident from behavioral tests. Pulses of increasing duration elicit responses in the pattern recognition neurons, which do not parallel the behavioral responses and indicate additional processing mechanisms. Long sound pulses elicit rhythmic rebound activity and additional bursts, whereas the feature detector neuron reveals a pulse duration filter, expanding our understanding of the pattern recognition process.
Collapse
Affiliation(s)
- Xinyang Zhang
- Department of Zoology, University of Cambridge, Cambridge, United Kingdom
| | - Berthold Hedwig
- Department of Zoology, University of Cambridge, Cambridge, United Kingdom
| |
Collapse
|
2
|
Zhang X, Hedwig B. Response properties of spiking and non-spiking brain neurons mirror pulse interval selectivity. Front Cell Neurosci 2022; 16:1010740. [PMID: 36246524 PMCID: PMC9559836 DOI: 10.3389/fncel.2022.1010740] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2022] [Accepted: 09/06/2022] [Indexed: 11/30/2022] Open
Abstract
In the bispotted field cricket auditory pulse pattern recognition of the species-specific calling song is based on a delay-line and coincidence detection network, established by the activity and synaptic connections of only 5 auditory neurons in the brain. To obtain a more detailed understanding of the network and the dynamic of the neural activity over time we analyzed the response properties of these neurons to test patterns, in which the pulse duration was kept constant while the duration of specific pulse intervals was systematically altered. We confirm that the ascending interneuron AN1 and the local interneuron LN2 copy the structure of the pulse pattern, however with limited resolution at short pulse intervals, further evident in downstream neural responses. In the non-spiking delay-line interneuron LN5 during long pulse intervals full-blown rebound potentials develop over a time course of 35–70 ms. LN5 also reveals an overall increase in its membrane potential tuned to chirps of the calling song pulse pattern. This may contribute to the pattern recognition process by driving the activity of the coincidence-detector LN3 and may indicate a further function of the delay-line neuron LN5. The activity of LN3 and of the feature detector LN4 match the tuning of the phonotactic behavior and demonstrate an increasingly sparse coding of the calling song pulse patterns as evident in the response of the feature detector LN4. The circuitry reveals a fundamental mechanism of auditory pattern recognition and demonstrates a principle of neuronal coding.
Collapse
|
3
|
Rogers SM, Kostarakos K, Hedwig B. An auditory-responsive interneuron descending from the cricket brain: a new element in the auditory pathway. J Comp Physiol A Neuroethol Sens Neural Behav Physiol 2022; 208:571-589. [PMID: 36208310 PMCID: PMC9734236 DOI: 10.1007/s00359-022-01577-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2022] [Revised: 09/02/2022] [Accepted: 09/22/2022] [Indexed: 12/14/2022]
Abstract
Crickets receive auditory information from their environment via ears located on the front legs. Ascending interneurons forward auditory activity to the brain, which houses a pattern recognition network for phonotaxis to conspecific calling songs and which controls negative phonotaxis to high-frequency sound pulses. Descending brain neurons, however, which are clearly involved in controlling these behaviors, have not yet been identified. We describe a descending auditory-responsive brain neuron with an arborization pattern that coincides with the ring-like auditory neuropil in the brain formed by the axonal arborizations of ascending and local interneurons, indicating its close link to auditory processing. Spiking activity of this interneuron occurs with a short latency to calling song patterns and the neuron copies the sound pulse pattern. The neuron preferentially responds to short sound pulses, but its activity appears to be independent of the calling song pattern recognition process. It also receives a weaker synaptic input in response to high-frequency pulses, which may contribute to its short latency spiking responses. This interneuron could be a crucial part in the auditory-to-motor transformation of the nervous system and contribute to the motor control of cricket auditory behavior.
Collapse
Affiliation(s)
- Stephen M. Rogers
- grid.5335.00000000121885934Department of Zoology, University of Cambridge, Cambridge, CB2 3EJ
UK ,grid.36511.300000 0004 0420 4262Department of Life Sciences, University of Lincoln, Brayford Pool Campus, Lincoln, LN6 7TS UK
| | | | - Berthold Hedwig
- grid.5335.00000000121885934Department of Zoology, University of Cambridge, Cambridge, CB2 3EJ
UK
| |
Collapse
|
4
|
Bent AM, Hedwig B. Tolerant pattern recognition: evidence from phonotactic responses in the cricket Gryllus bimaculatus (de Geer). Proc Biol Sci 2021; 288:20211889. [PMID: 34905710 PMCID: PMC8670955 DOI: 10.1098/rspb.2021.1889] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2021] [Accepted: 11/22/2021] [Indexed: 11/21/2022] Open
Abstract
When the amplitude modulation of species-specific acoustic signals is distorted in the transmission channel, signals become difficult to recognize by the receiver. Tolerant auditory pattern recognition systems, which after having perceived the correct species-specific signal transiently broaden their acceptance of signals, would be advantageous for animals as an adaptation to the constraints of the environment. Using a well-studied cricket species, Gryllus bimaculatus, we analysed tolerance in auditory steering responses to 'Odd' chirps, mimicking a signal distorted by the transmission channel, and control 'Silent' chirps by employing a fine-scale open-loop trackball system. Odd chirps on their own did not elicit a phonotactic response. However, when inserted into a calling song pattern with attractive Normal chirps, the females' phonotactic response toward these patterns was significantly larger than to patterns with Silent chirps. Moreover, females actively steered toward Odd chirps when these were presented within a sequence of attractive chirps. Our results suggest that crickets employ a tolerant pattern recognition system that, once activated, transiently allows responses to distorted sound patterns, as long as sufficient natural chirps are present. As pattern recognition modulates how crickets process non-attractive acoustic signals, the finding is also relevant for the interpretation of two-choice behavioural experiments.
Collapse
Affiliation(s)
- Adam M. Bent
- Department of Zoology, University of Cambridge, Downing Street, Cambridge CB2 3EJ, UK
| | - Berthold Hedwig
- Department of Zoology, University of Cambridge, Downing Street, Cambridge CB2 3EJ, UK
| |
Collapse
|
5
|
Ando N, Shidara H, Hommaru N, Ogawa H. Auditory Virtual Reality for Insect Phonotaxis. JOURNAL OF ROBOTICS AND MECHATRONICS 2021. [DOI: 10.20965/jrm.2021.p0494] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Insects have a sophisticated ability to navigate real environments. Virtual reality (VR) is a powerful tool for analyzing animal navigation in laboratory studies and is the most successful when used in the study of visually guided behaviors. However, the use of VR with non-visual sensory information, such as sound, on which nocturnal insects rely, for analyzing animal navigation has not been fully studied. We developed an auditory VR for the study of auditory navigation in crickets, Gryllus bimaculatus. The system consisted of a spherical treadmill on which a tethered female cricket walked. Sixteen speakers were placed around the cricket for auditory stimuli. The two optical mice attached to the treadmill measured the cricket’s locomotion, and the sound pressure and direction of the auditory stimuli were controlled at 100 Hz based on the position and heading of the cricket relative to a sound source in a virtual arena. We demonstrated that tethered female crickets selectively responded to the conspecific male calling song and localized the sound source in a virtual arena, which was similar to the behavior of freely walking crickets. Further combinations of our system with neurophysiological techniques will help understand the neural mechanisms for insect auditory navigation.
Collapse
|
6
|
Sarmiento-Ponce EJ, Rogers S, Hedwig B. Does the choosiness of female crickets change as they age? J Exp Biol 2021; 224:jeb241802. [PMID: 34114627 PMCID: PMC8214831 DOI: 10.1242/jeb.241802] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2020] [Accepted: 04/26/2021] [Indexed: 11/20/2022]
Abstract
For crickets, which approach singing males by phonotaxis, the female choosiness hypothesis postulates that young females should be more selective of male calling song patterns than older individuals. However, there is no information about the behavioural preferences of females over their complete adulthood. We analysed phonotaxis in female Gryllus bimaculatus throughout their entire adult lifetime and measured the impact of sound amplitude, carrier frequency and the temporal pattern of test songs on their auditory response. Females of all ages demonstrated their best responses to male calling songs with a pulse period of 34-42 ms, a carrier frequency of 4.5 kHz and a sound pressure level of 75 dB. The response profile to somewhat less optimal song types did vary with age, but not in a manner consistent with a simple loosening of selectiveness in older females. Age, however, had an effect on the overall strength of phonotaxis, as very old females showed an overall diminishing response to all song types. Our data suggest that although there are minor changes in the relative preferences of crickets to individual song elements as they age, the breadth of song patterns to which they will perform phonotaxis remains similar across age groups.
Collapse
Affiliation(s)
| | | | - Berthold Hedwig
- Department of Zoology, University of Cambridge, Cambridge CB2 3EJ, UK
| |
Collapse
|
7
|
Neurophysiology goes wild: from exploring sensory coding in sound proof rooms to natural environments. J Comp Physiol A Neuroethol Sens Neural Behav Physiol 2021; 207:303-319. [PMID: 33835199 PMCID: PMC8079291 DOI: 10.1007/s00359-021-01482-6] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2021] [Revised: 03/21/2021] [Accepted: 03/23/2021] [Indexed: 10/27/2022]
Abstract
To perform adaptive behaviours, animals have to establish a representation of the physical "outside" world. How these representations are created by sensory systems is a central issue in sensory physiology. This review addresses the history of experimental approaches toward ideas about sensory coding, using the relatively simple auditory system of acoustic insects. I will discuss the empirical evidence in support of Barlow's "efficient coding hypothesis", which argues that the coding properties of neurons undergo specific adaptations that allow insects to detect biologically important acoustic stimuli. This hypothesis opposes the view that the sensory systems of receivers are biased as a result of their phylogeny, which finally determine whether a sound stimulus elicits a behavioural response. Acoustic signals are often transmitted over considerable distances in complex physical environments with high noise levels, resulting in degradation of the temporal pattern of stimuli, unpredictable attenuation, reduced signal-to-noise levels, and degradation of cues used for sound localisation. Thus, a more naturalistic view of sensory coding must be taken, since the signals as broadcast by signallers are rarely equivalent to the effective stimuli encoded by the sensory system of receivers. The consequences of the environmental conditions for sensory coding are discussed.
Collapse
|
8
|
Römer H. Directional hearing in insects: biophysical, physiological and ecological challenges. ACTA ACUST UNITED AC 2020; 223:223/14/jeb203224. [PMID: 32737067 DOI: 10.1242/jeb.203224] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Sound localisation is a fundamental attribute of the way that animals perceive their external world. It enables them to locate mates or prey, determine the direction from which a predator is approaching and initiate adaptive behaviours. Evidence from different biological disciplines that has accumulated over the last two decades indicates how small insects with body sizes much smaller than the wavelength of the sound of interest achieve a localisation performance that is similar to that of mammals. This Review starts by describing the distinction between tympanal ears (as in grasshoppers, crickets, cicadas, moths or mantids) and flagellar ears (specifically antennae in mosquitoes and fruit flies). The challenges faced by insects when receiving directional cues differ depending on whether they have tympanal or flagellar years, because the latter respond to the particle velocity component (a vector quantity) of the sound field, whereas the former respond to the pressure component (a scalar quantity). Insects have evolved sophisticated biophysical solutions to meet these challenges, which provide binaural cues for directional hearing. The physiological challenge is to reliably encode these cues in the neuronal activity of the afferent auditory system, a non-trivial problem in particular for those insect systems composed of only few nerve cells which exhibit a considerable amount of intrinsic and extrinsic response variability. To provide an integrative view of directional hearing, I complement the description of these biophysical and physiological solutions by presenting findings on localisation in real-world situations, including evidence for localisation in the vertical plane.
Collapse
Affiliation(s)
- Heiner Römer
- Institute of Biology, University of Graz, Universitätsplatz 2, 8010 Graz, Austria
| |
Collapse
|
9
|
Lv M, Zhang X, Hedwig B. Phonotactic steering and representation of directional information in the ascending auditory pathway of a cricket. J Neurophysiol 2020; 123:865-875. [PMID: 31913780 DOI: 10.1152/jn.00737.2019] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Directional hearing is crucial for animals depending on acoustic signals to locate a mate. We focused on crickets to explore the reliability of directional information forwarded to the brain by the ascending auditory interneuron AN1, which is crucial for phonotactic behavior. We presented calling song from -45° to +45° in steps of 3° and compared the phonotactic steering of females walking on a trackball with the directional responses of AN1. Forty percent of females showed good steering behavior and changed their walking direction when the speaker passed the body's longitudinal axis. The bilateral latency difference between right and left AN1 responses was small and may not be reliable for auditory steering. In respect to spike count, all AN1 recordings presented significant bilateral differences for angles larger than ±18°, yet 35% showed a mean significant difference of 1-3 action potentials per chirp when the frontal stimulus deviated by 3° from their length axis. For small angles, some females had a very similar AN1 activity forwarded to the brain, but the accuracy of their steering behavior was substantially different. Our results indicate a correlation between directional steering and the response strength of AN1, especially for large angles. The reliable steering of animals at small angles would have to be based on small bilateral differences of AN1 activity, if AN1 is the only source providing directional information. We discuss whether such bilateral response difference at small angles can provide a reliable measure to generate auditory steering commands descending from the brain, as pattern recognition is intensity independent.NEW & NOTEWORTHY The ascending auditory interneuron AN1 has been implicated in cricket auditory steering, but at small acoustic stimulation angles, it does not provide reliable directional information. We conclude that either the small bilateral auditory activity differences of the AN1 neurons are enhanced to generate reliable descending steering commands or, more likely, directional auditory steering is mediated via a thoracic pathway, as indicated by the reactive steering hypothesis.
Collapse
Affiliation(s)
- M Lv
- Department of Range Land Ecology, China Agricultural University, Beijing, China
| | - X Zhang
- Department of Zoology, University of Cambridge, Cambridge, United Kingdom
| | - B Hedwig
- Department of Zoology, University of Cambridge, Cambridge, United Kingdom
| |
Collapse
|
10
|
Anthropogenic calling sites boost the sound amplitude of advertisement calls produced by a tropical cricket. Anim Behav 2018. [DOI: 10.1016/j.anbehav.2018.05.021] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
|
11
|
The ‘hot male’ hypothesis: do female crickets prefer males with increased body temperature in mate choice scenarios? Anim Behav 2018. [DOI: 10.1016/j.anbehav.2018.02.007] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
|
12
|
Sarmiento-Ponce EJ, Sutcliffe MPF, Hedwig B. Substrate texture affects female cricket walking response to male calling song. ROYAL SOCIETY OPEN SCIENCE 2018; 5:172334. [PMID: 29657819 PMCID: PMC5882743 DOI: 10.1098/rsos.172334] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/22/2017] [Accepted: 02/07/2018] [Indexed: 06/08/2023]
Abstract
Field crickets are extensively used as a model organism to study female phonotactic walking behaviour, i.e. their attraction to the male calling song. Laboratory-based phonotaxis experiments generally rely on arena or trackball-based settings; however, no attention has been paid to the effect of substrate texture on the response. Here, we tested phonotaxis in female Gryllus bimaculatus, walking on trackballs machined from methyl-methacrylate foam with different cell sizes. Surface height variations of the trackballs, due to the cellular composition of the material, were measured with profilometry and characterized as smooth, medium or rough, with roughness amplitudes of 7.3, 16 and 180 µm. Female phonotaxis was best on a rough and medium trackball surface, a smooth surface resulted in a significant lower phonotactic response. Claws of the cricket foot were crucial for effective walking. Females insert their claws into the surface pores to allow mechanical interlocking with the substrate texture and a high degree of attachment, which cannot be established on smooth surfaces. These findings provide insight to the biomechanical basis of insect walking and may inform behavioural studies that the surface texture on which walking insects are tested is crucial for the resulting behavioural response.
Collapse
Affiliation(s)
- E. J. Sarmiento-Ponce
- Department of Zoology, University of Cambridge, Downing Street, Cambridge CB2 3EJ, UK
| | - M. P. F. Sutcliffe
- Department of Engineering, University of Cambridge, Trumpington Street, Cambridge CB2 1PZ, UK
| | - B. Hedwig
- Department of Zoology, University of Cambridge, Downing Street, Cambridge CB2 3EJ, UK
| |
Collapse
|
13
|
Bertram SM, Loranger MJ, Thomson IR, Harrison SJ, Ferguson GL, Reifer ML, Corlett DH, Gowaty PA. Choosy males in Jamaican field crickets. Anim Behav 2017. [DOI: 10.1016/j.anbehav.2017.09.016] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
|
14
|
Lankheet MJ, Cerkvenik U, Larsen ON, van Leeuwen JL. Frequency tuning and directional sensitivity of tympanal vibrations in the field cricket Gryllus bimaculatus. J R Soc Interface 2017; 14:rsif.2017.0035. [PMID: 28298611 DOI: 10.1098/rsif.2017.0035] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2017] [Accepted: 02/20/2017] [Indexed: 11/12/2022] Open
Abstract
Female field crickets use phonotaxis to locate males by their calling song. Male song production and female behavioural sensitivity form a pair of matched frequency filters, which in Gryllus bimaculatus are tuned to a frequency of about 4.7 kHz. Directional sensitivity is supported by an elaborate system of acoustic tracheae, which make the ears function as pressure difference receivers. As a result, phase differences between left and right sound inputs are transformed into vibration amplitude differences. Here we critically tested the hypothesis that acoustic properties of internal transmissions play a major role in tuning directional sensitivity to the calling song frequency, by measuring tympanal vibrations as a function of sound direction and frequency. Rather than sharp frequency tuning of directional sensitivity corresponding to the calling song, we found broad frequency tuning, with optima shifted to higher frequencies. These findings agree with predictions from a vector summation model for combining external and internal sounds. We show that the model provides robust directional sensitivity that is, however, broadly tuned with an optimum well above the calling song frequency. We therefore advocate that additional filtering, e.g. at a higher (neuronal) level, significantly contributes to frequency tuning of directional sensitivity.
Collapse
Affiliation(s)
- Martin J Lankheet
- Experimental Zoology Group, Department of Animal Sciences, Wageningen University, De Elst 1, Wageningen, The Netherlands
| | - Uroš Cerkvenik
- Experimental Zoology Group, Department of Animal Sciences, Wageningen University, De Elst 1, Wageningen, The Netherlands
| | - Ole N Larsen
- Sound and Behavior Group, Department of Biology, University of Southern Denmark, Campusvej 55, Odense M, Denmark
| | - Johan L van Leeuwen
- Experimental Zoology Group, Department of Animal Sciences, Wageningen University, De Elst 1, Wageningen, The Netherlands
| |
Collapse
|
15
|
Hedwig B, Sarmiento-Ponce EJ. Song pattern recognition in crickets based on a delay-line and coincidence-detector mechanism. Proc Biol Sci 2017; 284:rspb.2017.0745. [PMID: 28539524 PMCID: PMC5454277 DOI: 10.1098/rspb.2017.0745] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2017] [Accepted: 04/24/2017] [Indexed: 11/30/2022] Open
Abstract
Acoustic communication requires filter mechanisms to process and recognize key features of the perceived signals. We analysed such a filter mechanism in field crickets (Gryllus bimaculatus), which communicate with species-specific repetitive patterns of sound pulses and chirps. A delay-line and coincidence-detection mechanism, in which each sound pulse has an impact on the processing of the following pulse, is implicated to underlie the recognition of the species-specific pulse pattern. Based on this concept, we hypothesized that altering the duration of a single pulse or inter-pulse interval in three-pulse chirps will lead to different behavioural responses. Phonotaxis was tested in female crickets walking on a trackball exposed to different sound paradigms. Changing the duration of either the first, second or third pulse of the chirps led to three different characteristic tuning curves. Long first pulses decreased the phonotactic response whereas phonotaxis remained strong when the third pulse was long. Chirps with three pulses of increasing duration of 5, 20 and 50 ms elicited phonotaxis, but the chirps were not attractive when played in reverse order. This demonstrates specific, pulse duration-dependent effects while sequences of pulses are processed. The data are in agreement with a mechanism in which processing of a sound pulse has an effect on the processing of the subsequent pulse, as outlined in the flow of activity in a delay-line and coincidence-detector circuit. Additionally our data reveal a substantial increase in the gain of phonotaxis, when the number of pulses of a chirp is increased from two to three.
Collapse
Affiliation(s)
- Berthold Hedwig
- Department of Zoology, Cambridge University, Downing Street, Cambridge CB2 3EJ, UK
| | | |
Collapse
|
16
|
Lee N, Mason AC. How spatial release from masking may fail to function in a highly directional auditory system. eLife 2017; 6. [PMID: 28425912 PMCID: PMC5443663 DOI: 10.7554/elife.20731] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2016] [Accepted: 04/19/2017] [Indexed: 11/13/2022] Open
Abstract
Spatial release from masking (SRM) occurs when spatial separation between a signal and masker decreases masked thresholds. The mechanically-coupled ears of Ormia ochracea are specialized for hyperacute directional hearing, but the possible role of SRM, or whether such specializations exhibit limitations for sound source segregation, is unknown. We recorded phonotaxis to a cricket song masked by band-limited noise. With a masker, response thresholds increased and localization was diverted away from the signal and masker. Increased separation from 6° to 90° did not decrease response thresholds or improve localization accuracy, thus SRM does not operate in this range of spatial separations. Tympanal vibrations and auditory nerve responses reveal that localization errors were consistent with changes in peripheral coding of signal location and flies localized towards the ear with better signal detection. Our results demonstrate that, in a mechanically coupled auditory system, specialization for directional hearing does not contribute to source segregation.
Collapse
Affiliation(s)
- Norman Lee
- Department of Biological Sciences, Integrative Behaviour and Neuroscience Group, University of Toronto Scarborough, Toronto, Canada
| | - Andrew C Mason
- Department of Biological Sciences, Integrative Behaviour and Neuroscience Group, University of Toronto Scarborough, Toronto, Canada
| |
Collapse
|
17
|
Gabel E, Vural P, Mariot L, Hennig RM. A gain control mechanism governs the weighting of acoustic signal intensity and attractiveness during female decisions. Anim Behav 2016. [DOI: 10.1016/j.anbehav.2016.10.019] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
|
18
|
Haberkern H, Hedwig B. Behavioural integration of auditory and antennal stimulation during phonotaxis in the field cricket Gryllus bimaculatus. J Exp Biol 2016; 219:3575-3586. [PMID: 27609761 PMCID: PMC5117196 DOI: 10.1242/jeb.141606] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2016] [Accepted: 08/30/2016] [Indexed: 11/20/2022]
Abstract
Animals need to flexibly respond to stimuli from their environment without compromising behavioural consistency. For example, female crickets orienting toward a conspecific male's calling song in search of a mating partner need to stay responsive to other signals that provide information about obstacles and predators. Here, we investigate how spontaneously walking crickets and crickets engaging in acoustically guided goal-directed navigation, i.e. phonotaxis, respond to mechanosensory stimuli detected by their long antennae. We monitored walking behaviour of female crickets on a trackball during lateral antennal stimulation, which was achieved by moving a wire mesh transiently into reach of one antenna. During antennal stimulation alone, females reduced their walking speed, oriented toward the object and actively explored it with antennal movements. Additionally, some crickets initially turned away from the approaching object. Females responded in a similar way when the antennal stimulus was presented during ongoing phonotaxis: forward velocity was reduced and phonotactic steering was suppressed while the females turned toward and explored the object. Further, rapid steering bouts to individual chirps, typical for female phonotaxis, no longer occurred. Our data reveal that in this experimental situation, antennal stimulation overrides phonotaxis for extended time periods. Phonotaxis in natural environments, which require the integration of multiple sensory cues, may therefore be more variable than phonotaxis measured under ideal laboratory conditions. Combining this new behavioural paradigm with neurophysiological methods will show where the sensory-motor integration of antennal and acoustic stimulation occurs and how this is achieved on a mechanistic level.
Collapse
Affiliation(s)
- Hannah Haberkern
- Department of Zoology, University of Cambridge, Downing St, Cambridge CB2 3EJ, UK
- Howard Hughes Medical Institute, Janelia Farm Research Campus, 19700 Helix Drive, Ashburn, VA 20147, USA
| | - Berthold Hedwig
- Department of Zoology, University of Cambridge, Downing St, Cambridge CB2 3EJ, UK
| |
Collapse
|
19
|
Gabel E, Gray DA, Matthias Hennig R. How females of chirping and trilling field crickets integrate the 'what' and 'where' of male acoustic signals during decision making. J Comp Physiol A Neuroethol Sens Neural Behav Physiol 2016; 202:823-837. [PMID: 27638304 DOI: 10.1007/s00359-016-1124-x] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2016] [Revised: 09/03/2016] [Accepted: 09/06/2016] [Indexed: 10/21/2022]
Abstract
In crickets acoustic communication serves mate selection. Female crickets have to perceive and integrate male cues relevant for mate choice while confronted with several different signals in an acoustically diverse background. Overall female decisions are based on the attractiveness of the temporal pattern (informative about the 'what') and on signal intensity (informative about the 'where') of male calling songs. Here, we investigated how the relevant cues for mate choice are integrated during the decision process by females of five different species of chirping and trilling field crickets. Using a behavioral design, female preferences in no-choice and choice situations for male calling songs differing in pulse rate, modulation depth, intensities, chirp/trill arrangements and temporal shifts were examined. Sensory processing underlying decisions in female field crickets is rather similar as combined evidence suggested that incoming song patterns were analyzed separately by bilaterally paired networks for pattern attractiveness and pattern intensity. A downstream gain control mechanism leads to a weighting of the intensity cue by pattern attractiveness. While remarkable differences between species were observed with respect to specific processing steps, closely related species exhibited more similar preferences than did more distantly related species.
Collapse
Affiliation(s)
- Eileen Gabel
- Department of Biology, Behavioral Physiology, Humboldt-Universität zu Berlin, Invalidenstraße 43, 10115, Berlin, Germany.
| | - David A Gray
- Department of Biology, California State University Northridge, Northridge, CA, USA
| | - R Matthias Hennig
- Department of Biology, Behavioral Physiology, Humboldt-Universität zu Berlin, Invalidenstraße 43, 10115, Berlin, Germany
| |
Collapse
|
20
|
Hedwig BG. Sequential Filtering Processes Shape Feature Detection in Crickets: A Framework for Song Pattern Recognition. Front Physiol 2016; 7:46. [PMID: 26941647 PMCID: PMC4766296 DOI: 10.3389/fphys.2016.00046] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2015] [Accepted: 02/01/2016] [Indexed: 11/13/2022] Open
Abstract
Intraspecific acoustic communication requires filtering processes and feature detectors in the auditory pathway of the receiver for the recognition of species-specific signals. Insects like acoustically communicating crickets allow describing and analysing the mechanisms underlying auditory processing at the behavioral and neural level. Female crickets approach male calling song, their phonotactic behavior is tuned to the characteristic features of the song, such as the carrier frequency and the temporal pattern of sound pulses. Data from behavioral experiments and from neural recordings at different stages of processing in the auditory pathway lead to a concept of serially arranged filtering mechanisms. These encompass a filter for the carrier frequency at the level of the hearing organ, and the pulse duration through phasic onset responses of afferents and reciprocal inhibition of thoracic interneurons. Further, processing by a delay line and coincidence detector circuit in the brain leads to feature detecting neurons that specifically respond to the species-specific pulse rate, and match the characteristics of the phonotactic response. This same circuit may also control the response to the species-specific chirp pattern. Based on these serial filters and the feature detecting mechanism, female phonotactic behavior is shaped and tuned to the characteristic properties of male calling song.
Collapse
|
21
|
Brizio A, Tirassa M. Biological Agency: Its Subjective Foundations and a Large-Scale Taxonomy. Front Psychol 2016; 7:41. [PMID: 26903891 PMCID: PMC4745100 DOI: 10.3389/fpsyg.2016.00041] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2015] [Accepted: 01/10/2016] [Indexed: 11/13/2022] Open
Abstract
We will outline a theory of agency cast in theoretical psychology, viewed as a branch of a non-eliminativist biology. Our proposal will be based on an evolutionary view of the nature and functioning of the mind(s), reconsidered in a radically subjectivist, radically constructivist framework. We will argue that the activities of control systems should be studied in terms of interaction. Specifically, what an agent does belongs to the coupling of its internal dynamics with the dynamics of the external world. The internal dynamics, rooted in the species' phylogenetic history as well as in the individual's ontogenetic path, (a) determine which external dynamics are relevant to the organism, that is, they create the subjective ontology that the organism senses in the external world, and (b) determine what types of activities and actions the agent is able to conceive of and to adopt in the current situation. The external dynamics that the organism senses thus constitute its subjective environment. This notion of coupling is basically suitable for whichever organism one may want to consider. However, remarkable differences exist between the ways in which coupling may be realized, that is, between different natures and ways of functioning of control systems. We will describe agency at different phylogenetic levels: at the very least, it is necessary to discriminate between non-Intentional species, Intentional species, and a subtype of the latter called meta-Intentional. We will claim that agency can only be understood in a radically subjectivist perspective, which in turn is best grounded in a view of the mind as consciousness and experience. We will thus advance a radically constructivist view of agency and of several correlate notions (like meaning and ontology).
Collapse
Affiliation(s)
- Adelina Brizio
- Faculty of Communication Science, Università della Svizzera Italiana Lugano, Switzerland
| | - Maurizio Tirassa
- Department of Psychology and Centre for Cognitive Science, University of Turin Torino, Italy
| |
Collapse
|
22
|
Abstract
Communication is fundamental for our understanding of behavior. In the acoustic modality, natural scenes for communication in humans and animals are often very noisy, decreasing the chances for signal detection and discrimination. We investigated the mechanisms enabling selective hearing under natural noisy conditions for auditory receptors and interneurons of an insect. In the studied katydid Mecopoda elongata species-specific calling songs (chirps) are strongly masked by signals of another species, both communicating in sympatry. The spectral properties of the two signals are similar and differ only in a small frequency band at 2 kHz present in the chirping species. Receptors sharply tuned to 2 kHz are completely unaffected by the masking signal of the other species, whereas receptors tuned to higher audio and ultrasonic frequencies show complete masking. Intracellular recordings of identified interneurons revealed two mechanisms providing response selectivity to the chirp. (1) Response selectivity is when several identified interneurons exhibit remarkably selective responses to the chirps, even at signal-to-noise ratios of -21 dB, since they are sharply tuned to 2 kHz. Their dendritic arborizations indicate selective connectivity with low-frequency receptors tuned to 2 kHz. (2) Novelty detection is when a second group of interneurons is broadly tuned but, because of strong stimulus-specific adaptation to the masker spectrum and "novelty detection" to the 2 kHz band present only in the conspecific signal, these interneurons start to respond selectively to the chirp shortly after the onset of the continuous masker. Both mechanisms provide the sensory basis for hearing at unfavorable signal-to-noise ratios. Significance statement: Animal and human acoustic communication may suffer from the same "cocktail party problem," when communication happens in noisy social groups. We address solutions for this problem in a model system of two katydids, where one species produces an extremely noisy sound, yet the second species still detects its own song. Using intracellular recording techniques we identified two neural mechanisms underlying the surprising behavioral signal detection at the level of single identified interneurons. These neural mechanisms for signal detection are likely to be important for other sensory modalities as well, where noise in the communication channel creates similar problems. Also, they may be used for the development of algorithms for the filtering of specific signals in technical microphones or hearing aids.
Collapse
|
23
|
Schöneich S, Kostarakos K, Hedwig B. An auditory feature detection circuit for sound pattern recognition. SCIENCE ADVANCES 2015; 1:e1500325. [PMID: 26601259 PMCID: PMC4643773 DOI: 10.1126/sciadv.1500325] [Citation(s) in RCA: 63] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/12/2015] [Accepted: 05/26/2015] [Indexed: 06/01/2023]
Abstract
From human language to birdsong and the chirps of insects, acoustic communication is based on amplitude and frequency modulation of sound signals. Whereas frequency processing starts at the level of the hearing organs, temporal features of the sound amplitude such as rhythms or pulse rates require processing by central auditory neurons. Besides several theoretical concepts, brain circuits that detect temporal features of a sound signal are poorly understood. We focused on acoustically communicating field crickets and show how five neurons in the brain of females form an auditory feature detector circuit for the pulse pattern of the male calling song. The processing is based on a coincidence detector mechanism that selectively responds when a direct neural response and an intrinsically delayed response to the sound pulses coincide. This circuit provides the basis for auditory mate recognition in field crickets and reveals a principal mechanism of sensory processing underlying the perception of temporal patterns.
Collapse
Affiliation(s)
| | | | - Berthold Hedwig
- Department of Zoology, University of Cambridge, Downing Street, Cambridge CB2 3EJ, UK
| |
Collapse
|
24
|
Veen T, Otto SP. Liking the good guys: amplifying local adaptation via the evolution of condition‐dependent mate choice. J Evol Biol 2015; 28:1804-15. [DOI: 10.1111/jeb.12696] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2015] [Revised: 06/28/2015] [Accepted: 07/13/2015] [Indexed: 11/28/2022]
Affiliation(s)
- T. Veen
- Biodiversity Research Centre University of British Columbia Vancouver BC Canada
- Department of Integrative Biology University of Texas at Austin Austin TX USA
| | - S. P. Otto
- Department of Zoology University of British Columbia Vancouver BC Canada
| |
Collapse
|
25
|
Chemical Orientation Strategies of the Crayfish are Influenced by the Hydrodynamics of their Native Environment. AMERICAN MIDLAND NATURALIST 2015. [DOI: 10.1674/0003-0031-173.1.17] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
|
26
|
Kostarakos K, Hedwig B. Pattern recognition in field crickets: concepts and neural evidence. J Comp Physiol A Neuroethol Sens Neural Behav Physiol 2014; 201:73-85. [PMID: 25348550 DOI: 10.1007/s00359-014-0949-4] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2014] [Revised: 09/29/2014] [Accepted: 10/01/2014] [Indexed: 11/30/2022]
Abstract
Since decades the acoustic communication behavior of crickets is in the focus of neurobiology aiming to analyze the neural basis of male singing and female phonotactic behavior. For temporal pattern recognition several different concepts have been proposed to elucidate the possible neural mechanisms underlying the tuning of phonotaxis in females. These concepts encompass either some form of a feature detecting mechanism using cross-correlation processing, temporal filter properties of brain neurons or an autocorrelation processing based on a delay-line and coincidence detection mechanism. Current data based on intracellular recordings of auditory brain neurons indicate a sequential processing by excitation and inhibition in a local auditory network within the protocerebrum. The response properties of the brain neurons point towards the concept of an autocorrelation-like mechanism underlying female pattern recognition in which delay-lines by long lasting inhibition may be involved.
Collapse
|
27
|
Pacheco K, Bertram SM. How male sound pressure level influences phonotaxis in virgin female Jamaican field crickets (Gryllus assimilis). PeerJ 2014; 2:e437. [PMID: 24949249 PMCID: PMC4060022 DOI: 10.7717/peerj.437] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2014] [Accepted: 05/29/2014] [Indexed: 11/20/2022] Open
Abstract
Understanding female mate preference is important for determining the strength and direction of sexual trait evolution. The sound pressure level (SPL) acoustic signalers use is often an important predictor of mating success because higher sound pressure levels are detectable at greater distances. If females are more attracted to signals produced at higher sound pressure levels, then the potential fitness impacts of signalling at higher sound pressure levels should be elevated beyond what would be expected from detection distance alone. Here we manipulated the sound pressure level of cricket mate attraction signals to determine how female phonotaxis was influenced. We examined female phonotaxis using two common experimental methods: spherical treadmills and open arenas. Both methods showed similar results, with females exhibiting greatest phonotaxis towards loud sound pressure levels relative to the standard signal (69 vs. 60 dB SPL) but showing reduced phonotaxis towards very loud sound pressure level signals relative to the standard (77 vs. 60 dB SPL). Reduced female phonotaxis towards supernormal stimuli may signify an acoustic startle response, an absence of other required sensory cues, or perceived increases in predation risk.
Collapse
Affiliation(s)
- Karen Pacheco
- Department of Biology, Carleton University , Ottawa, ON , Canada
| | - Susan M Bertram
- Department of Biology, Carleton University , Ottawa, ON , Canada
| |
Collapse
|
28
|
Abstract
A wide variety of insects use spatial memories in behaviours like holding a position in air or flowing water, in returning to a place of safety, and in foraging. The Hymenoptera, in particular, have evolved life-histories requiring reliable spatial memories to support the task of provisioning their young. Behavioural experiments, primarily on social bees and ants, reveal the mechanisms by which these memories are employed for guidance to spatial goals and suggest how the memories, and the processing streams that use them, may be organized. We discuss three types of memory-based guidance which, together, can explain a large part of observed insect spatial behaviour. Two of these, alignment image-matching and positional image-matching, are based on an insect's remembered views of its surroundings: The first uses views to keep to a familiar heading and the second to head towards a familiar place. The third type of guidance is based on a process of path integration by which an insect monitors its distance and direction from its nest through odometric and compass information. To a large degree, these guidance mechanisms appear to involve modular computational systems. We discuss the lack of evidence for cognitive maps in insects, and in particular the evidence against a map based on path integration, in which view-based and path integration memories might be combined. We suggest instead that insects have a collective of separate guidance systems, which cooperate and train each other, and together provide reliable guidance over a range of conditions.
Collapse
Affiliation(s)
- Matthew Collett
- Department of Psychology, University of Exeter, Perry Rd, Exeter EX4 4QG, Devon, UK.
| | | | | |
Collapse
|
29
|
Seagraves KM, Hedwig B. Phase shifts in binaural stimuli provide directional cues for sound localisation in the field cricket Gryllus bimaculatus. ACTA ACUST UNITED AC 2014; 217:2390-8. [PMID: 24737767 DOI: 10.1242/jeb.101402] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
The cricket's auditory system is a highly directional pressure difference receiver whose function is hypothesised to depend on phase relationships between the sound waves propagating through the auditory trachea that connects the left and right hearing organs. We tested this hypothesis by measuring the effect of experimentally constructed phase shifts in acoustic stimuli on phonotactic behavior of Gryllus bimaculatus, the oscillatory response patterns of the tympanic membrane, and the activity of the auditory afferents. The same artificial calling song was played simultaneously at the left and right sides of the cricket, but one sound pattern was shifted in phase by 90 deg (carrier frequencies between 3.6 and 5.4 kHz). All three levels of auditory processing are sensitive to experimentally induced acoustic phase shifts, and the response characteristics are dependent on the carrier frequency of the sound stimulus. At lower frequencies, crickets steered away from the sound leading in phase, while tympanic membrane vibrations and auditory afferent responses were smaller when the ipsilateral sound was leading. In contrast, opposite responses were observed at higher frequencies in all three levels of auditory processing. Minimal responses occurred near the carrier frequency of the cricket's calling song, suggesting a stability at this frequency. Our results indicate that crickets may use directional cues arising from phase shifts in acoustic signals for sound localisation, and that the response properties of pressure difference receivers may be analysed with phase-shifted sound stimuli to further our understanding of how insect auditory systems are adapted for directional processing.
Collapse
Affiliation(s)
- Kelly M Seagraves
- Department of Zoology, University of Cambridge, Downing Street, Cambridge CB2 3EJ, UK Howard Hughes Medical Institute, Janelia Farm Research Campus, 19700 Helix Drive, Ashburn, VA 20147, USA
| | - Berthold Hedwig
- Department of Zoology, University of Cambridge, Downing Street, Cambridge CB2 3EJ, UK
| |
Collapse
|
30
|
Hirtenlehner S, Römer H. Selective phonotaxis of female crickets under natural outdoor conditions. J Comp Physiol A Neuroethol Sens Neural Behav Physiol 2014; 200:239-50. [PMID: 24488017 PMCID: PMC3929774 DOI: 10.1007/s00359-014-0881-7] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2013] [Revised: 01/07/2014] [Accepted: 01/10/2014] [Indexed: 10/27/2022]
Abstract
Acoustic mate choice in insects has been extensively studied under laboratory conditions, using different behavioural paradigms. Ideally, however, mate choice designs should reflect natural conditions, including the physical properties of the transmission channel for the signal. Since little is known about the discrimination ability of females between male song variants under natural conditions, we performed phonotaxis experiments with female field crickets (Gryllus bimaculatus) outdoors, using two-choice decisions based on differences in carrier frequency, sound pressure level, and chirp rate. For all three song parameters, minimum differences necessary for a significant preference between two song models were considerably larger outdoors compared to laboratory conditions. A minimum amplitude difference of 5 dB was required for a significant choice in the field, compared to only 1-2 dB reported for lab-based experiments. Due to the tuned receiver system, differences in carrier frequency equal differences in perceived loudness, and the results on choice for differences in carrier frequency corroborate those in amplitude. Similarly, chirp rate differences of 50 chirps/min were required outdoors compared to only 20 chirps/min in the lab. For predictions about patterns of sexual selection, future studies need to consider the different outcomes of mate choice decisions in lab and field trials.
Collapse
Affiliation(s)
- Stefan Hirtenlehner
- Department of Zoology, Karl-Franzens-University, Universitätsplatz 2, 8010, Graz, Austria,
| | | |
Collapse
|
31
|
Oe M, Ogawa H. Neural basis of stimulus-angle-dependent motor control of wind-elicited walking behavior in the cricket Gryllus bimaculatus. PLoS One 2013; 8:e80184. [PMID: 24244644 PMCID: PMC3828193 DOI: 10.1371/journal.pone.0080184] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2013] [Accepted: 10/08/2013] [Indexed: 11/18/2022] Open
Abstract
Crickets exhibit oriented walking behavior in response to air-current stimuli. Because crickets move in the opposite direction from the stimulus source, this behavior is considered to represent ‘escape behavior’ from an approaching predator. However, details of the stimulus-angle-dependent control of locomotion during the immediate phase, and the neural basis underlying the directional motor control of this behavior remain unclear. In this study, we used a spherical-treadmill system to measure locomotory parameters including trajectory, turn angle and velocity during the immediate phase of responses to air-puff stimuli applied from various angles. Both walking direction and turn angle were correlated with stimulus angle, but their relationships followed different rules. A shorter stimulus also induced directionally-controlled walking, but reduced the yaw rotation in stimulus-angle-dependent turning. These results suggest that neural control of the turn angle requires different sensory information than that required for oriented walking. Hemi-severance of the ventral nerve cords containing descending axons from the cephalic to the prothoracic ganglion abolished stimulus-angle-dependent control, indicating that this control required descending signals from the brain. Furthermore, we selectively ablated identified ascending giant interneurons (GIs) in vivo to examine their functional roles in wind-elicited walking. Ablation of GI8-1 diminished control of the turn angle and decreased walking distance in the initial response. Meanwhile, GI9-1b ablation had no discernible effect on stimulus-angle-dependent control or walking distance, but delayed the reaction time. These results suggest that the ascending signals conveyed by GI8-1 are required for turn-angle control and maintenance of walking behavior, and that GI9-1b is responsible for rapid initiation of walking. It is possible that individual types of GIs separately supply the sensory signals required to control wind-elicited walking.
Collapse
Affiliation(s)
- Momoko Oe
- Graduate School of Life Science, Hokkaido University, Sapporo, Japan
| | - Hiroto Ogawa
- Department of Biological Sciences, Faculty of Science, Hokkaido University, Sapporo, Japan
- PREST, Japan Science and Technology Agency (JST), Kawaguchi, Japan
- * E-mail:
| |
Collapse
|
32
|
Pacheco K, Dawson JW, Jutting M, Bertram SM. How age influences phonotaxis in virgin female Jamaican field crickets (Gryllus assimilis). PeerJ 2013; 1:e130. [PMID: 23940839 PMCID: PMC3740142 DOI: 10.7717/peerj.130] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2013] [Accepted: 07/21/2013] [Indexed: 12/21/2022] Open
Abstract
Female mating preference can be a dominant force shaping the evolution of sexual signals. However, females rarely have consistent mating preferences throughout their lives. Preference flexibility results from complex interactions of predation risk, social and sexual experience, and age. Because residual reproductive value should theoretically decline with age, older females should not be as choosy as younger females. We explored how age influences phonotaxis towards a standard mate attraction signal using a spherical treadmill (trackball) and a no-choice experimental protocol. Female Jamaican field crickets, Gryllus assimilis, were highly variable in their phonotaxis; age explained up to 64% of this variation. Females 10 days post imaginal eclosion and older oriented toward the mate attraction signal, with 10- and 13-day females exhibiting the greatest movement in the direction of the signal. Our study suggests 10- and 13-day old females would be most responsive when quantifying the preference landscape for G. assimilis sexual signals.
Collapse
Affiliation(s)
- Karen Pacheco
- Department of Biology, Carleton University , Ottawa, Ontario , Canada
| | | | | | | |
Collapse
|
33
|
Hirtenlehner S, Küng S, Kainz F, Römer H. Asymmetry in cricket song: female preference and proximate mechanism of discrimination. ACTA ACUST UNITED AC 2013; 216:2046-54. [PMID: 23470661 PMCID: PMC3699250 DOI: 10.1242/jeb.083774] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Subtle random deviations from perfect symmetry in bilateral traits are suggested to signal reduced phenotypic and genetic quality of a sender, but little is known about the related receiver mechanisms for discriminating symmetrical from asymmetrical traits. Here, we investigated these mechanisms in behavioural and neurophysiological experiments in the Mediterranean field cricket, Gryllus bimaculatus. A downward frequency modulation at the end of each syllable in the calling song has been suggested to indicate morphological asymmetry in sound radiating structures between left and right forewings. Even under ideal laboratory conditions on a trackball system, female crickets only discriminated between songs of symmetrical and asymmetrical males in two-choice experiments at carrier frequencies of 4.4 kHz and a large modulation depth of 600 and 800 Hz. Under these conditions they preferred the pure-tone calling songs over the modulated (asymmetrical) alternative, whereas no preference was observed at carrier frequencies of 4.9 and 5.2 kHz. These preferences correlate well with the responses of a pair of identified auditory interneurons (AN1), known for their importance in female phonotaxis. The AN1 interneuron is tuned to an average frequency of 4.9 kHz, and the roll-off towards lower and higher frequencies determines the magnitude of responses to pure-tone and frequency-modulated calling songs. The difference in response magnitude between the two neurons appears to drive the decision of females towards the song alternatives. We discuss the relevance of song differences based on asymmetry in the morphology of song-producing structures under natural conditions.
Collapse
|
34
|
Meckenhäuser G, Hennig RM, Nawrot MP. Critical song features for auditory pattern recognition in crickets. PLoS One 2013; 8:e55349. [PMID: 23437054 PMCID: PMC3577835 DOI: 10.1371/journal.pone.0055349] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2012] [Accepted: 12/31/2012] [Indexed: 11/18/2022] Open
Abstract
Many different invertebrate and vertebrate species use acoustic communication for pair formation. In the cricket Gryllus bimaculatus, females recognize their species-specific calling song and localize singing males by positive phonotaxis. The song pattern of males has a clear structure consisting of brief and regular pulses that are grouped into repetitive chirps. Information is thus present on a short and a long time scale. Here, we ask which structural features of the song critically determine the phonotactic performance. To this end we employed artificial neural networks to analyze a large body of behavioral data that measured females' phonotactic behavior under systematic variation of artificially generated song patterns. In a first step we used four non-redundant descriptive temporal features to predict the female response. The model prediction showed a high correlation with the experimental results. We used this behavioral model to explore the integration of the two different time scales. Our result suggested that only an attractive pulse structure in combination with an attractive chirp structure reliably induced phonotactic behavior to signals. In a further step we investigated all feature sets, each one consisting of a different combination of eight proposed temporal features. We identified feature sets of size two, three, and four that achieve highest prediction power by using the pulse period from the short time scale plus additional information from the long time scale.
Collapse
Affiliation(s)
- Gundula Meckenhäuser
- Theoretical Neuroscience and Neuroinformatics, Institute of Biology, Freie Universität Berlin, Berlin, Germany.
| | | | | |
Collapse
|
35
|
Wilson AD, Golonka S. Embodied Cognition is Not What you Think it is. Front Psychol 2013; 4:58. [PMID: 23408669 PMCID: PMC3569617 DOI: 10.3389/fpsyg.2013.00058] [Citation(s) in RCA: 173] [Impact Index Per Article: 15.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2012] [Accepted: 01/26/2013] [Indexed: 11/30/2022] Open
Abstract
The most exciting hypothesis in cognitive science right now is the theory that cognition is embodied. Like all good ideas in cognitive science, however, embodiment immediately came to mean six different things. The most common definitions involve the straight-forward claim that “states of the body modify states of the mind.” However, the implications of embodiment are actually much more radical than this. If cognition can span the brain, body, and the environment, then the “states of mind” of disembodied cognitive science won’t exist to be modified. Cognition will instead be an extended system assembled from a broad array of resources. Taking embodiment seriously therefore requires both new methods and theory. Here we outline four key steps that research programs should follow in order to fully engage with the implications of embodiment. The first step is to conduct a task analysis, which characterizes from a first person perspective the specific task that a perceiving-acting cognitive agent is faced with. The second step is to identify the task-relevant resources the agent has access to in order to solve the task. These resources can span brain, body, and environment. The third step is to identify how the agent can assemble these resources into a system capable of solving the problem at hand. The last step is to test the agent’s performance to confirm that agent is actually using the solution identified in step 3. We explore these steps in more detail with reference to two useful examples (the outfielder problem and the A-not-B error), and introduce how to apply this analysis to the thorny question of language use. Embodied cognition is more than we think it is, and we have the tools we need to realize its full potential.
Collapse
Affiliation(s)
- Andrew D Wilson
- School of Social, Psychological and Communication Sciences, Leeds Metropolitan University Leeds, UK
| | | |
Collapse
|
36
|
Veen T, Faulks J, Tyler F, Lloyd J, Tregenza T. Diverse reproductive barriers in hybridising crickets suggests extensive variation in the evolution and maintenance of isolation. Evol Ecol 2012. [DOI: 10.1007/s10682-012-9610-2] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
|
37
|
Zorović M, Hedwig B. Descending brain neurons in the cricket Gryllus bimaculatus (de Geer): auditory responses and impact on walking. J Comp Physiol A Neuroethol Sens Neural Behav Physiol 2012; 199:25-34. [PMID: 23104703 DOI: 10.1007/s00359-012-0765-7] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2012] [Revised: 09/25/2012] [Accepted: 09/30/2012] [Indexed: 11/30/2022]
Abstract
The activity of four types of sound-sensitive descending brain neurons in the cricket Gryllus bimaculatus was recorded intracellularly while animals were standing or walking on an open-loop trackball system. In a neuron with a contralaterally descending axon, the male calling song elicited responses that copied the pulse pattern of the song during standing and walking. The accuracy of pulse copying increased during walking. Neurons with ipsilaterally descending axons responded weakly to sound only during standing. The responses were mainly to the first pulse of each chirp, whereas the complete pulse pattern of a chirp was not copied. During walking the auditory responses were suppressed in these neurons. The spiking activity of all four neuron types was significantly correlated to forward walking velocity, indicating their relevance for walking. Additionally, injection of depolarizing current elicited walking and/or steering in three of four neuron types described. In none of the neurons was the spiking activity both sufficient and necessary to elicit and maintain walking behaviour. Some neurons showed arborisations in the lateral accessory lobes, pointing to the relevance of this brain region for cricket audition and descending motor control.
Collapse
Affiliation(s)
- Maja Zorović
- Department of Entomology, National Institute of Biology, Večna pot 111, 1000 Ljubljana, Slovenia
| | | |
Collapse
|
38
|
Calling song recognition in female crickets: temporal tuning of identified brain neurons matches behavior. J Neurosci 2012; 32:9601-12. [PMID: 22787046 DOI: 10.1523/jneurosci.1170-12.2012] [Citation(s) in RCA: 74] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Phonotactic orientation of female crickets is tuned to the temporal pattern of the male calling song. We analyzed the phonotactic selectivity of female crickets to varying temporal features of calling song patterns and compared it with the auditory response properties of the ascending interneuron AN1 (herein referred to as TH1-AC1) and four newly identified local brain neurons. The neurites of all brain neurons formed a ring-like branching pattern in the anterior protocerebrum that overlapped with the axonal arborizations of TH1-AC1. All brain neurons responded phasically to the sound pulses of a species-specific chirp. The spike activity of TH1-AC1 and the local interneuron, B-LI2, copied different auditory patterns regardless of their temporal structure. Two other neurons, B-LI3 and B-LC3, matched the temporal selectivity of the phonotactic responses but also responded to some nonattractive patterns. Neuron B-LC3 linked the bilateral auditory areas in the protocerebrum. One local brain neuron, B-LI4, received inhibitory as well as excitatory synaptic inputs. Inhibition was particularly pronounced for nonattractive pulse patterns, reducing its spike activity. When tested with different temporal patterns, B-LI4 exhibited bandpass response properties; its different auditory response functions significantly matched the tuning of phonotaxis. Temporal selectivity was established already for the second of two sound pulses separated by one species-specific pulse interval. Temporal pattern recognition in the cricket brain occurs within the anterior protocerebrum at the first stage of auditory processing. It is crucially linked to a change in auditory responsiveness during pulse intervals and based on fast interactions of inhibition and excitation.
Collapse
|
39
|
Ritzmann RE, Harley CM, Daltorio KA, Tietz BR, Pollack AJ, Bender JA, Guo P, Horomanski AL, Kathman ND, Nieuwoudt C, Brown AE, Quinn RD. Deciding which way to go: how do insects alter movements to negotiate barriers? Front Neurosci 2012; 6:97. [PMID: 22783160 PMCID: PMC3390555 DOI: 10.3389/fnins.2012.00097] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2012] [Accepted: 06/13/2012] [Indexed: 11/13/2022] Open
Abstract
Animals must routinely deal with barriers as they move through their natural environment. These challenges require directed changes in leg movements and posture performed in the context of ever changing internal and external conditions. In particular, cockroaches use a combination of tactile and visual information to evaluate objects in their path in order to effectively guide their movements in complex terrain. When encountering a large block, the insect uses its antennae to evaluate the object’s height then rears upward accordingly before climbing. A shelf presents a choice between climbing and tunneling that depends on how the antennae strike the shelf; tapping from above yields climbing, while tapping from below causes tunneling. However, ambient light conditions detected by the ocelli can bias that decision. Similarly, in a T-maze turning is determined by antennal contact but influenced by visual cues. These multi-sensory behaviors led us to look at the central complex as a center for sensori-motor integration within the insect brain. Visual and antennal tactile cues are processed within the central complex and, in tethered preparations, several central complex units changed firing rates in tandem with or prior to altered step frequency or turning, while stimulation through the implanted electrodes evoked these same behavioral changes. To further test for a central complex role in these decisions, we examined behavioral effects of brain lesions. Electrolytic lesions in restricted regions of the central complex generated site specific behavioral deficits. Similar changes were also found in reversible effects of procaine injections in the brain. Finally, we are examining these kinds of decisions made in a large arena that more closely matches the conditions under which cockroaches forage. Overall, our studies suggest that CC circuits may indeed influence the descending commands associated with navigational decisions, thereby making them more context dependent.
Collapse
Affiliation(s)
- Roy E Ritzmann
- Department of Biology, Case Western Reserve University Cleveland, OH, USA
| | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
40
|
Takalo J, Piironen A, Honkanen A, Lempeä M, Aikio M, Tuukkanen T, Vähäsöyrinki M. A fast and flexible panoramic virtual reality system for behavioural and electrophysiological experiments. Sci Rep 2012; 2:324. [PMID: 22442752 PMCID: PMC3310229 DOI: 10.1038/srep00324] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2012] [Accepted: 02/27/2012] [Indexed: 11/09/2022] Open
Abstract
Ideally, neuronal functions would be studied by performing experiments with unconstrained animals whilst they behave in their natural environment. Although this is not feasible currently for most animal models, one can mimic the natural environment in the laboratory by using a virtual reality (VR) environment. Here we present a novel VR system based upon a spherical projection of computer generated images using a modified commercial data projector with an add-on fish-eye lens. This system provides equidistant visual stimulation with extensive coverage of the visual field, high spatio-temporal resolution and flexible stimulus generation using a standard computer. It also includes a track-ball system for closed-loop behavioural experiments with walking animals. We present a detailed description of the system and characterize it thoroughly. Finally, we demonstrate the VR system’s performance whilst operating in closed-loop conditions by showing the movement trajectories of the cockroaches during exploratory behaviour in a VR forest.
Collapse
|
41
|
Veen T, Faulks J, Rodríguez-Muñoz R, Tregenza T. Premating reproductive barriers between hybridising cricket species differing in their degree of polyandry. PLoS One 2011; 6:e19531. [PMID: 21573165 PMCID: PMC3088677 DOI: 10.1371/journal.pone.0019531] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2010] [Accepted: 04/04/2011] [Indexed: 11/18/2022] Open
Abstract
Understanding speciation hinges on understanding how reproductive barriers arise between incompletely isolated populations. Despite their crucial role in speciation, prezygotic barriers are relatively poorly understood and hard to predict. We use two closely related cricket species, Gryllus bimaculatus and G. campestris, to experimentally investigate premating barriers during three sequential mate choice steps. Furthermore, we experimentally show a significant difference in polyandry levels between the two species and subsequently test the hypothesis that females of the more polyandrous species, G. bimaculatus, will be less discriminating against heterospecific males and hence hybridise more readily. During close-range mating behaviour experiments, males showed relatively weak species discrimination but females discriminated very strongly. In line with our predictions, this discrimination is asymmetric, with the more polyandrous G. bimaculatus mating heterospecifically and G. campestris females never mating heterospecifically. Our study shows clear differences in the strength of reproductive isolation during the mate choice process depending on sex and species, which may have important consequences for the evolution of reproductive barriers.
Collapse
Affiliation(s)
- Thor Veen
- Centre for Ecology and Conservation, College of Life and Environmental Sciences, University of Exeter, Penryn, Cornwall, United Kingdom.
| | | | | | | |
Collapse
|
42
|
Witney AG, Hedwig B. Kinematics of phonotactic steering in the walking cricket Gryllus bimaculatus (de Geer). ACTA ACUST UNITED AC 2011; 214:69-79. [PMID: 21147970 DOI: 10.1242/jeb.044800] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Female crickets, Gryllus bimaculatus, are attracted by the male calling song and approach singing males; a behaviour known as phonotaxis. Even tethered females walking on a trackball steer towards a computer-generated male song presented from their left or right side. High-speed video analysis showed how this auditory-evoked steering was integrated with walking. Typically all the front and middle legs showed kinematic adjustments during steering, with the trajectories tilted towards the side of acoustic stimulation. Furthermore, the average speed of the tarsi contralateral to song increased relative to the ipsilateral tarsi. Kinematic changes of the hind legs were small and may be a consequence of the front and middle leg adjustments. Although phonotactic steering generally led to stereotyped adjustments there were differences in the specific combination of kinematic changes in leg trajectories. The most reliable kinematic steering response was by the contralateral front leg, such that, during its swing phase the tarsus moved towards the side of acoustic stimulation through an increased forward rotation of the femur and an increased extension of the tibia. Relating the changes in tarsal positioning of each leg to the steering velocity of the animal indicated that typically the front and middle legs contralateral to song generated the turning forces. Phonotactic steering was integrated into forward walking without changes to the walking motor cycle.
Collapse
Affiliation(s)
- Alice G Witney
- Department of Physiology, Trinity College Institute of Neuroscience and Trinity Centre for Bioengineering, Trinity College Dublin, Dublin 2, Ireland
| | | |
Collapse
|
43
|
Zorović M, Hedwig B. Processing of species-specific auditory patterns in the cricket brain by ascending, local, and descending neurons during standing and walking. J Neurophysiol 2011; 105:2181-94. [PMID: 21346206 DOI: 10.1152/jn.00416.2010] [Citation(s) in RCA: 52] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
The recognition of the male calling song is essential for phonotaxis in female crickets. We investigated the responses toward different models of song patterns by ascending, local, and descending neurons in the brain of standing and walking crickets. We describe results for two ascending, three local, and two descending interneurons. Characteristic dendritic and axonal arborizations of the local and descending neurons indicate a flow of auditory information from the ascending interneurons toward the lateral accessory lobes and point toward the relevance of this brain region for cricket phonotaxis. Two aspects of auditory processing were studied: the tuning of interneuron activity to pulse repetition rate and the precision of pattern copying. Whereas ascending neurons exhibited weak, low-pass properties, local neurons showed both low- and band-pass properties, and descending neurons represented clear band-pass filters. Accurate copying of single pulses was found at all three levels of the auditory pathway. Animals were walking on a trackball, which allowed an assessment of the effect that walking has on auditory processing. During walking, all neurons were additionally activated, and in most neurons, the spike rate was correlated to walking velocity. The number of spikes elicited by a chirp increased with walking only in ascending neurons, whereas the peak instantaneous spike rate of the auditory responses increased on all levels of the processing pathway. Extra spiking activity resulted in a somewhat degraded copying of the pulse pattern in most neurons.
Collapse
Affiliation(s)
- M Zorović
- Department of Zoology, University of Cambridge, Downing St., Cambridge CB2 3EJ, UK
| | | |
Collapse
|
44
|
Schöneich S, Hedwig B. Hyperacute directional hearing and phonotactic steering in the cricket (Gryllus bimaculatus deGeer). PLoS One 2010; 5:e15141. [PMID: 21170344 PMCID: PMC2999563 DOI: 10.1371/journal.pone.0015141] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2010] [Accepted: 10/25/2010] [Indexed: 11/19/2022] Open
Abstract
Background Auditory mate or prey localisation is central to the lifestyle of many animals and requires precise directional hearing. However, when the incident angle of sound approaches 0° azimuth, interaural time and intensity differences gradually vanish. This poses a demanding challenge to animals especially when interaural distances are small. To cope with these limitations imposed by the laws of acoustics, crickets employ a frequency tuned peripheral hearing system. Although this enhances auditory directionality the actual precision of directional hearing and phonotactic steering has never been studied in the behaviourally important frontal range. Principal Findings Here we analysed the directionality of phonotaxis in female crickets (Gryllus bimaculatus) walking on an open-loop trackball system by measuring their steering accuracy towards male calling song presented at frontal angles of incidence. Within the range of ±30°, females reliably discriminated the side of acoustic stimulation, even when the sound source deviated by only 1° from the animal's length axis. Moreover, for angles of sound incidence between 1° and 6° the females precisely walked towards the sound source. Measuring the tympanic membrane oscillations of the front leg ears with a laser vibrometer revealed between 0° and 30° a linear increasing function of interaural amplitude differences with a slope of 0.4 dB/°. Auditory nerve recordings closely reflected these bilateral differences in afferent response latency and intensity that provide the physiological basis for precise auditory steering. Conclusions Our experiments demonstrate that an insect hearing system based on a frequency-tuned pressure difference receiver achieves directional hyperacuity which easily rivals best directional hearing in mammals and birds. Moreover, this directional accuracy of the cricket's hearing system is reflected in the animal's phonotactic motor response.
Collapse
Affiliation(s)
- Stefan Schöneich
- Department of Zoology, University of Cambridge, Cambridge, United Kingdom
- * E-mail: (SS); (BH)
| | - Berthold Hedwig
- Department of Zoology, University of Cambridge, Cambridge, United Kingdom
- * E-mail: (SS); (BH)
| |
Collapse
|
45
|
Fast and reliable decisions for a dynamic song parameter in field crickets. J Comp Physiol A Neuroethol Sens Neural Behav Physiol 2010; 197:131-5. [PMID: 20878165 DOI: 10.1007/s00359-010-0589-2] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2010] [Revised: 09/07/2010] [Accepted: 09/14/2010] [Indexed: 10/19/2022]
Abstract
We investigated the choice of female crickets for a dynamic song parameter (chirp rate) on a walking compensator, and the underlying neuronal basis for the choice in the form of discharge differences in the pair of AN1-neurons driving the phonotactic steering behaviour. Our analysis reveals that decisions about chirp rate in a choice situation are made fast and reliably by female crickets. They steered towards the higher chirp rate after a delay of only 2.2-6 s, depending on the rate difference between the song alternatives. In this time period, the female experienced only one to two additional chirps in the song model with the higher rate. There was a strong correlation between the accumulated AN1 discharge difference and the amount of steering towards the side with the stronger response.
Collapse
|
46
|
Kostarakos K, Hennig MR, Römer H. Two matched filters and the evolution of mating signals in four species of cricket. Front Zool 2009; 6:22. [PMID: 19785724 PMCID: PMC2760545 DOI: 10.1186/1742-9994-6-22] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2009] [Accepted: 09/28/2009] [Indexed: 11/29/2022] Open
Abstract
Background Male field crickets produce pure-tone calling songs to attract females. Receivers are expected to have evolved a "matched filter" in the form of a tuned sensitivity for this frequency. In addition, the peripheral directionality of field crickets is sharply tuned as a result of a pressure difference receiver. We studied both forms of tuning in the same individuals of four species of cricket, where Gryllus bimaculatus and G. campestris are largely allopatric, whereas Teleogryllus oceanicus and T. commodus occur also sympatrically. Results The sharpness of the sensitivity filter is highest for T. commodus, which also exhibits low interindividual variability. Individual receivers may also vary strongly in the best frequency for directional hearing. In G. campestris, such best frequencies occur even at frequencies outside the range of carrier frequencies of males. Contrary to the predictions from the "matched filter hypothesis", in three of the four species the frequency optima of the two involved filters are not matched to each other, and the mismatch can amount to 1.2 kHz. The mean carrier frequency of the male population is between the frequency optima of both filters in three species. Only in T. commodus we found a match between both filters and the male carrier frequency. Conclusion Our results show that a mismatch between the sensitivity and directionality tuning is not uncommon in crickets, and an observed match (T. commodus) appears to be the exception rather than the rule. The data suggests that independent variation of both filters is possible. During evolution each sensory task may have been driven by independent constraints, and may have evolved towards its own respective optimum.
Collapse
|
47
|
Mhatre N, Balakrishnan R. Predicting acoustic orientation in complex real-world environments. ACTA ACUST UNITED AC 2008; 211:2779-85. [PMID: 18723535 DOI: 10.1242/jeb.017756] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Animals have to accomplish several tasks in their lifetime, such as finding food and mates and avoiding predators. Animals that locate these using sound need to detect, recognize and localize appropriate acoustic objects in their environment, typically in noisy, non-ideal conditions. Quantitative models attempting to explain or predict animal behaviour should be able to accurately simulate behaviour in such complex, real-world conditions. Female crickets locate potential mates in choruses of simultaneously calling males. In the present study, we have tested field cricket acoustic orientation behaviour in complex acoustic conditions in the field and also successfully predicted female orientation and paths under these conditions using a simulation model based on auditory physiology. Such simulation models can provide powerful tools to predict and dissect patterns of behaviour in complex, natural environments.
Collapse
Affiliation(s)
- Natasha Mhatre
- Centre for Ecological Sciences, Indian Institute of Science, Bangalore, 560012, India
| | | |
Collapse
|
48
|
Baden T, Hedwig B. Front leg movements and tibial motoneurons underlying auditory steering in the cricket (Gryllus bimaculatus deGeer). ACTA ACUST UNITED AC 2008; 211:2123-33. [PMID: 18552302 DOI: 10.1242/jeb.019125] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Front leg movements in the cricket (Gryllus bimaculatus) were measured during phonotactic steering on a trackball together with electromyogram recordings of the tibial extensor and flexor muscles. Up-down leg movements clearly indicated the step cycle and were independent of auditory stimulation. By contrast, left-right movements of the front leg were dependent on sound direction, with crickets performing rapid steering leg movements towards the active speaker. Steering movements were dependent on the phase of sound relative to the step cycle, and were greatest for sounds occurring during the swing phase. During phonotaxis the slow extensor tibiae motoneuron responded to ipsilateral sounds with a latency of 35-40 ms, whereas the fast flexor tibiae motoneurons were excited by contralateral sound. We made intracellular recordings of two tibial extensor and at least eight flexor motoneurons. The fast extensor tibiae, the slow extensor tibiae and one fast flexor tibiae motoneurons were individually identifiable, but a group of at least four fast flexor tibiae as well as at least three slow flexor tibiae motoneurons of highly similar morphology could not be distinguished. Motoneurons received descending inputs from cephalic ganglia and from local prothoracic networks. There was no overlap between the dendritic fields of the tibial motoneurons and the auditory neuropile. They did not respond to auditory stimulation at rest. Neither extracellular stimulation of descending pathways nor pharmacological activation of prothoracic motor networks changed the auditory responsiveness. Therefore, any auditory input to tibial motoneurons is likely to be indirect, possibly via the brain.
Collapse
Affiliation(s)
- T Baden
- Department of Zoology, University of Cambridge, Downing Street, Cambridge, UK
| | | |
Collapse
|
49
|
|
50
|
Kostarakos K, Hartbauer M, Römer H. Matched filters, mate choice and the evolution of sexually selected traits. PLoS One 2008; 3:e3005. [PMID: 18714350 PMCID: PMC2500168 DOI: 10.1371/journal.pone.0003005] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2008] [Accepted: 07/31/2008] [Indexed: 11/29/2022] Open
Abstract
Background Fundamental for understanding the evolution of communication systems is both the variation in a signal and how this affects the behavior of receivers, as well as variation in preference functions of receivers, and how this affects the variability of the signal. However, individual differences in female preference functions and their proximate causation have rarely been studied. Methodology/Principal Findings Calling songs of male field crickets represent secondary sexual characters and are subject to sexual selection by female choice. Following predictions from the “matched filter hypothesis” we studied the tuning of an identified interneuron in a field cricket, known for its function in phonotaxis, and correlated this with the preference of the same females in two-choice trials. Females vary in their neuronal frequency tuning, which strongly predicts the preference in a choice situation between two songs differing in carrier frequency. A second “matched filter” exists in directional hearing, where reliable cues for sound localization occur only in a narrow frequency range. There is a strong correlation between the directional tuning and the behavioural preference in no-choice tests. This second “matched filter” also varies widely in females, and surprisingly, differs on average by 400 Hz from the neuronal frequency tuning. Conclusions/Significance Our findings on the mismatch of the two “matched filters” would suggest that the difference in these two filters appears to be caused by their evolutionary history, and the different trade-offs which exist between sound emission, transmission and detection, as well as directional hearing under specific ecological settings. The mismatched filter situation may ultimately explain the maintenance of considerable variation in the carrier frequency of the male signal despite stabilizing selection.
Collapse
Affiliation(s)
| | | | - Heiner Römer
- Zoology, Karl-Franzens-University, Graz, Austria
- * E-mail:
| |
Collapse
|