Johnston's organ

Last updated

Johnston's organ is a collection of sensory cells found in the pedicel (the second segment) of the antennae in the class Insecta. [1] Johnston's organ detects motion in the flagellum (third and typically final antennal segment). It consists of scolopidia arrayed in a bowl shape, each of which contains a mechanosensory chordotonal neuron. [2] [3] The number of scolopidia varies between species. In homopterans, the Johnston's organs contain 25 - 79 scolopidia. [4] The presence of Johnston's organ is a defining characteristic which separates the class Insecta from the other hexapods belonging to the group Entognatha. Johnston's organ was named after the physician Christopher Johnston, [5] father of the physician and Assyriologist Christopher Johnston.

Contents

Uses of the Johnston's organ

In fruit flies, nonbiting midges and mosquitoes

In the fruit fly Drosophila melanogaster and Chironomus annularius , the Johnston's organ contains almost 480 sensory neurons. [6] In the mosquito, the Johnston's organ houses ~15 000 sensory cells in males, [7] comparable to that in the human cochlea, [8] and approximately half as many in females. [9] Distinct populations of neurons are activated differently by deflections of antennae caused by gravity or by vibrations caused by sound or air movement. This differential response allows the fly to distinguish between gravitational, mechanical, and acoustic stimuli. [1] [10]

The Johnston's organ of fruit flies, chironomids or mosquitoes can be used to detect air vibrations caused by the wingbeat frequency or courtship song of a mate. One function of the Johnston's organ is for detecting the wing beat frequency of a mate. [2] Production of sound in air results in two energy components: the pressure component, which is changes in air pressure; and the particle displacement component, which is the back and forth vibration of air particles oscillating in the direction of sound propagation. [11] Particle displacement has greater energy loss than the pressure component when getting further from the sound source, so for quiet sounds such as small flies, it is detectable only within a few wavelengths of the source. [11]

Insects, such as fruit flies and bees, detect sounds using loosely attached hairs or antennae which vibrate with air particle movement. [11] (Tympanal organs detect the pressure component of sound.) Near-field sound, because of the rapid dissipation of energy, is suitable only for very close communication. [11] Two examples of near-field sound communication are bee's waggle dance and Drosophila courtship songs. [11] In fruit flies, the arista of the antennae and the third segment act as the sound receiver. [11] Vibrations of the receiver cause rotation of the third segment, which channels sound input to the mechanoreceptors of the Johnston's organ. [11]

In hawk moths

The Johnston's organ plays a role in the control of flight stability in hawk moths. Kinematic data measured from hovering moths during steady flight indicate that the antennae vibrate with a frequency matching wingbeat (27 Hz). During complex flight, however, angular changes of the flying moth cause Coriolis forces, which are predicted to manifest as a vibration of the antenna of at about twice wingbeat frequency (~60 Hz). When antennae were manipulated to vibrate at a range of frequencies and the resulting signals from the neurons associated with the Johnston's organs were measured, the response of the scolopidia neurons to the frequency was tightly coupled in the range of 50–70 Hz, which is the predicted range of vibrations caused by Coriolis effects. Thus, the Johnston's organ is tuned to detect angular changes during maneuvering in complex flight. [12]

In honeybees

Dancing honeybees ( Apis mellifera ) describe the location of nearby food sources by emitted airborne sound signals. These signals consist of rhythmic high-velocity movement of air particles. These near-field sounds are received and interpreted using the Johnston's organ in the pedicel of the antennae. [13] Honeybees also perceive electric field changes via the Johnston's organs in their antennae and possibly other mechanoreceptors. Electric fields generated by movements of the wings cause displacements of the antennae based on Coulomb's law. Neurons of the Johnston's organ respond to movements within the range of displacements caused by electric fields. When the antennae were prevented from moving at the joints containing the Johnston's organ, bees no longer responded to biologically relevant electric fields. Honeybees respond differently to different temporal patterns. Honeybees appear to use the electric field emanating from the dancing bee for distance communication. [14] [15]

Related Research Articles

<span class="mw-page-title-main">Halteres</span> Pair of small club-shaped insect organs

Halteres are a pair of small club-shaped organs on the body of two orders of flying insects that provide information about body rotations during flight. Insects of the large order Diptera (flies) have halteres which evolved from a pair of ancestral hindwings, while males of the much smaller order Strepsiptera (stylops) have halteres which evolved from a pair of ancestral forewings.

<span class="mw-page-title-main">Cochlea</span> Snail-shaped part of inner ear involved in hearing

The cochlea is the part of the inner ear involved in hearing. It is a spiral-shaped cavity in the bony labyrinth, in humans making 2.75 turns around its axis, the modiolus. A core component of the cochlea is the organ of Corti, the sensory organ of hearing, which is distributed along the partition separating the fluid chambers in the coiled tapered tube of the cochlea.

<span class="mw-page-title-main">Sensory nervous system</span> Part of the nervous system

The sensory nervous system is a part of the nervous system responsible for processing sensory information. A sensory system consists of sensory neurons, neural pathways, and parts of the brain involved in sensory perception and interoception. Commonly recognized sensory systems are those for vision, hearing, touch, taste, smell, balance and visceral sensation. Sense organs are transducers that convert data from the outer physical world to the realm of the mind where people interpret the information, creating their perception of the world around them.

<span class="mw-page-title-main">Lateral line</span> Sensory system in fish

The lateral line, also called the lateral line organ (LLO), is a system of sensory organs found in fish, used to detect movement, vibration, and pressure gradients in the surrounding water. The sensory ability is achieved via modified epithelial cells, known as hair cells, which respond to displacement caused by motion and transduce these signals into electrical impulses via excitatory synapses. Lateral lines play an important role in schooling behavior, predation, and orientation.

Stimulus modality, also called sensory modality, is one aspect of a stimulus or what is perceived after a stimulus. For example, the temperature modality is registered after heat or cold stimulate a receptor. Some sensory modalities include: light, sound, temperature, taste, pressure, and smell. The type and location of the sensory receptor activated by the stimulus plays the primary role in coding the sensation. All sensory modalities work together to heighten stimuli sensation when necessary.

A mechanoreceptor, also called mechanoceptor, is a sensory receptor that responds to mechanical pressure or distortion. Mechanoreceptors are innervated by sensory neurons that convert mechanical pressure into electrical signals that, in animals, are sent to the central nervous system.

<span class="mw-page-title-main">Auditory system</span> Sensory system used for hearing

The auditory system is the sensory system for the sense of hearing. It includes both the sensory organs and the auditory parts of the sensory system.

<span class="mw-page-title-main">Hair cell</span> Auditory sensory receptor nerve cells

Hair cells are the sensory receptors of both the auditory system and the vestibular system in the ears of all vertebrates, and in the lateral line organ of fishes. Through mechanotransduction, hair cells detect movement in their environment.

<span class="mw-page-title-main">Range fractionation</span>

Range fractionation is a term used in biology to describe the way by which a group of sensory neurons are able to encode varying magnitudes of a stimulus. Sense organs are usually composed of many sensory receptors measuring the same property. These sensory receptors show a limited degree of precision due to an upper limit in firing rate. If the receptors are endowed with distinct transfer functions in such a way that the points of highest sensitivity are scattered along the axis of the quality being measured, the precision of the sense organ as a whole can be increased.

<span class="mw-page-title-main">Lateral inhibition</span> Capacity of an excited neuron to reduce activity of its neighbors

In neurobiology, lateral inhibition is the capacity of an excited neuron to reduce the activity of its neighbors. Lateral inhibition disables the spreading of action potentials from excited neurons to neighboring neurons in the lateral direction. This creates a contrast in stimulation that allows increased sensory perception. It is also referred to as lateral antagonism and occurs primarily in visual processes, but also in tactile, auditory, and even olfactory processing. Cells that utilize lateral inhibition appear primarily in the cerebral cortex and thalamus and make up lateral inhibitory networks (LINs). Artificial lateral inhibition has been incorporated into artificial sensory systems, such as vision chips, hearing systems, and optical mice. An often under-appreciated point is that although lateral inhibition is visualised in a spatial sense, it is also thought to exist in what is known as "lateral inhibition across abstract dimensions." This refers to lateral inhibition between neurons that are not adjacent in a spatial sense, but in terms of modality of stimulus. This phenomenon is thought to aid in colour discrimination.

Chordotonal organs are stretch receptor organs found only in insects and crustaceans. They are located at most joints and are made up of clusters of scolopidia that either directly or indirectly connect two joints and sense their movements relative to one another. They can have both extero- and proprioceptive functions, for example sensing auditory stimuli or leg movement. The word was coined by Vitus Graber in 1882, though he interpreted them as being stretched between two points like a string, sensing vibrations through resonance.

<span class="mw-page-title-main">Tympanal organ</span> Hearing organ in insects

A tympanal organ is a hearing organ in insects, consisting of a membrane (tympanum) stretched across a frame backed by an air sac and associated sensory neurons. Sounds vibrate the membrane, and the vibrations are sensed by a chordotonal organ. Hymenoptera do not have a tympanal organ, but they do have a Johnston's organ.

<span class="mw-page-title-main">Hearing</span> Sensory perception of sound by living organisms

Hearing, or auditory perception, is the ability to perceive sounds through an organ, such as an ear, by detecting vibrations as periodic changes in the pressure of a surrounding medium. The academic field concerned with hearing is auditory science.

A sense is a biological system used by an organism for sensation, the process of gathering information about the surroundings through the detection of stimuli. Although, in some cultures, five human senses were traditionally identified as such, many more are now recognized. Senses used by non-human organisms are even greater in variety and number. During sensation, sense organs collect various stimuli for transduction, meaning transformation into a form that can be understood by the brain. Sensation and perception are fundamental to nearly every aspect of an organism's cognition, behavior and thought.

<span class="mw-page-title-main">Jamming avoidance response</span> Behavior performed by weakly electric fish to prevent jamming of their sense of electroreception

The jamming avoidance response is a behavior of some species of weakly electric fish. It occurs when two electric fish with wave discharges meet – if their discharge frequencies are very similar, each fish shifts its discharge frequency to increase the difference between the two. By doing this, both fish prevent jamming of their sense of electroreception.

Feature detection is a process by which the nervous system sorts or filters complex natural stimuli in order to extract behaviorally relevant cues that have a high probability of being associated with important objects or organisms in their environment, as opposed to irrelevant background or noise.

<span class="mw-page-title-main">Scolopidia</span>

A scolopidium is the fundamental unit of a mechanoreceptor organ in insects. It is a composition of three cells: a scolopale cap cell which caps the scolopale cell, and a bipolar sensory nerve cell.

<span class="mw-page-title-main">Pain in invertebrates</span> Contentious issue

Pain in invertebrates is a contentious issue. Although there are numerous definitions of pain, almost all involve two key components. First, nociception is required. This is the ability to detect noxious stimuli which evokes a reflex response that moves the entire animal, or the affected part of its body, away from the source of the stimulus. The concept of nociception does not necessarily imply any adverse, subjective feeling; it is a reflex action. The second component is the experience of "pain" itself, or suffering—i.e., the internal, emotional interpretation of the nociceptive experience. Pain is therefore a private, emotional experience. Pain cannot be directly measured in other animals, including other humans; responses to putatively painful stimuli can be measured, but not the experience itself. To address this problem when assessing the capacity of other species to experience pain, argument-by-analogy is used. This is based on the principle that if a non-human animal's responses to stimuli are similar to those of humans, it is likely to have had an analogous experience. It has been argued that if a pin is stuck in a chimpanzee's finger and they rapidly withdraw their hand, then argument-by-analogy implies that like humans, they felt pain. It has been questioned why the inference does not then follow that a cockroach experiences pain when it writhes after being stuck with a pin. This argument-by-analogy approach to the concept of pain in invertebrates has been followed by others.

Most fish possess highly developed sense organs. Nearly all daylight fish have colour vision that is at least as good as a human's. Many fish also have chemoreceptors that are responsible for extraordinary senses of taste and smell. Although they have ears, many fish may not hear very well. Most fish have sensitive receptors that form the lateral line system, which detects gentle currents and vibrations, and senses the motion of nearby fish and prey. Sharks can sense frequencies in the range of 25 to 50 Hz through their lateral line.

<span class="mw-page-title-main">Subgenual organ</span>

The subgenual organ is an organ in insects that is involved in the perception of sound. The name refers to the location of the organ just below the knee in the tibia of all legs in most insects.

References

  1. 1 2 Kamikouchi, A; Inagaki, HK; Effertz, T; Hendrich, O; Fiala, A; Göpfert, MC; Ito, K (2009). "The neural basis of Drosophila gravity-sensing and hearing" (PDF). Nature. 458 (7235): 165–71. doi:10.1038/nature07810. PMID   19279630. S2CID   1171792.
  2. 1 2 Göpfert, MC; Robert, D (May 2002). "The mechanical basis of Drosophila audition". Journal of Experimental Biology. 205 (Pt 9): 1199–208. doi:10.1242/jeb.205.9.1199. PMID   11948197.
  3. ↑ Yack, JE (April 2004). "The structure and function of auditory chordotonal organs in insects". Microscopy Research and Technique. 63 (6): 315–37. doi:10.1002/jemt.20051. PMID   15252876. S2CID   16942117.
  4. ↑ Rossi Stacconi, Marco Valerio; Romani, Roberto (2013). "The Johnston's organ of three homopteran species: A comparative ultrastructural study". Arthropod Structure and Development. 42 (3): 219–228. doi:10.1016/j.asd.2013.02.001. PMID   23428838.
  5. ↑ Johnston, C (1855). "Auditory Apparatus of the Culex Mosquito" (PDF). Quarterly Journal of Microscopical Science. 3: 97–102.
  6. ↑ Kamikouchi, A.; Shimada, T.; Ito, K. (2006). "Comprehensive classification of the auditory sensory functions in the brain of the fruit fly Drosophila melanogaster". Journal of Comparative Neurology. 499 (3): 317–356. doi:10.1002/cne.21075. PMID   16998934. S2CID   41474430.
  7. ↑ Boo, K.S. and Richards, A.G. (1975). "Fine structure of the scolopidia in the Johnston's organ of male Aedes aegypti (l.) (diptera: Culicidae)". International Journal of Insect Morphology and Embryology. 4 (6): 549–566. doi:10.1016/0020-7322(75)90031-8.{{cite journal}}: CS1 maint: multiple names: authors list (link)
  8. ↑ Robles, L. and Ruggero, M.A. (2001). "Mechanics of the mammalian cochlea". Physiological Reviews. 81 (3): 1305–1352. doi:10.1152/physrev.2001.81.3.1305. PMC   3590856 . PMID   11427697.{{cite journal}}: CS1 maint: multiple names: authors list (link)
  9. ↑ Boo, K.S. and Richards, A.G. (1975). "Fine structure of scolopidia in Johnston's organ of female Aedes aegypti compared with that of the male". Journal of Insect Physiology. 21 (5): 1129–1139. doi:10.1016/0022-1910(75)90126-2. PMID   1141704.{{cite journal}}: CS1 maint: multiple names: authors list (link)
  10. ↑ Yorozu, S.; Wong, A.; Fischer, B.J.; Dankert, H.; Kerman, J.J.; Kamikouchi, A.; Ito, K.; Anderson, D.J. (2009). "Distinct sensory representations of wind and near-field sound in the Drosophila brain". Nature. 428 (7235): 201–5. doi:10.1038/nature07843. PMC   2755041 . PMID   19279637.
  11. 1 2 3 4 5 6 7 Tauber, E.; Eberl, D. F. (2003). "Acoustic communication in Drosophila". Behavioural Processes. 64 (2): 197–210. doi:10.1016/s0376-6357(03)00135-9. S2CID   140209323.
  12. ↑ Sane, Sanjay P.; Dieudonne, Alexandre; Willis, Mark A.; Daniel, Thomas L. (2007). "Antennal Mechanosensors Mediate Flight Control in Moths". Science. 315 (5813): 863–866. CiteSeerX   10.1.1.205.7318 . doi:10.1126/science.1133598. PMID   17290001. S2CID   2429129.
  13. ↑ Dreller, C.; Kirchner, W. H. (1993). "Hearing in honeybees: localization of the auditory sense organ". Journal of Comparative Physiology A. 173 (3): 275–279. doi:10.1007/bf00212691. S2CID   9802172.
  14. ↑ Greggers, Uwe; Koch G; Schmidt V; Dürr A; Floriou-Servou A; Piepenbrock D; Göpfert MC; Menzel R (22 May 2013). "Reception and learning of electric fields". Proceedings of the Royal Society B . 280 (1759): 20130528. doi:10.1098/rspb.2013.0528. PMC   3619523 . PMID   23536603.
  15. ↑ Greggers, Uwe. "ESF in bees". Archived from the original on 2018-11-21. Retrieved 2013-06-11.
This page is based on this Wikipedia article
Text is available under the CC BY-SA 4.0 license; additional terms may apply.
Images, videos and audio are available under their respective licenses.