• synaptic
  • Although it has been reported in invertebrates that almost all sensory systems (including olfactory) adapt to stimuli variations and display synaptic plasticity, similarly to mammals, the cellular and molecular mechanisms, and more particularly, the involvement of the internal Ca 2+ stores remain relatively unexplored. (biologists.org)
  • The axon terminals of the ORNs make synaptic contact with dendrites of a few uniglomerular projection neurons (PNs), which propagate olfactory information to higher brain centers, such as the mushroom bodies. (biologists.org)
  • Here, we address the question of whether the formation of olfactory long-term memory (LTM) could be associated with changes in the synaptic architecture of the MB networks. (jneurosci.org)
  • For this, we took advantage of the modular architecture of the honeybee MB neuropil, where synaptic contacts between olfactory input and MB neurons are segregated into discrete units (microglomeruli) which can be easily visualized and counted. (jneurosci.org)
  • ORNs
  • However, in invertebrates, especially in sensory neurons such as ORNs, similar mechanisms have not yet been detected. (biologists.org)
  • Furthermore, we show that disrupting the intracellular Ca 2+ stores in the ORNs has functional consequences since Ins P 3 R- or RyR-RNAi expressing flies were defective in olfactory behavior. (biologists.org)
  • Moreover, only appropriate pairing of frontonasal epithelial and mesenchymal partners yields ORNs, VRNs, and GnRH neurons. (harvard.edu)
  • mammals
  • Graziadei GAM and Graziadei PPC (1979) Neurogenesis and neuron regeneration in the olfactory system of mammals. (els.net)
  • While most chemoreceptors in mammals are metabotropic receptors, chemoreception in insects is ionotropic. (frontiersin.org)
  • The olfactory system provides mammals with the ability to perceive a large number of structurally diverse odorous molecules, often at minute concentrations, and to discriminate subtle differences in molecular structure. (jneurosci.org)
  • The components of insulin signaling, including the insulin homolog INS-1, its receptor DAF-2, and the PIP3-kinase homolog AGE-1, are highly conserved between C. elegans and mammals. (jneurosci.org)
  • While the mechanisms through which these receptors operate is unclear, recent discoveries have shown that mammals have at least two distinct types of thermoreceptors. (wikipedia.org)
  • Neural receptor cells that process and receive stimulation go through constant changes for mammals and other living organisms to sense vital changes in their environment. (wikipedia.org)
  • vertebrate
  • This approach allows unambiguous identification of connexins and determination of the membrane "sidedness" and the identities of connexin coupling partners in homotypic and heterotypic gap junctions of vertebrate neurons. (deepdyve.com)
  • OSNs
  • This way, the direct responses of OSNs to retinoids during late stages of olfactory map formation and maintenance may be selectively examined. (jneurosci.org)
  • Together, the results indicate that a GABA B receptor is expressed in pheromone-responsive OSNs of H. virescens and suggest a presynaptic gain control mechanism in the axon terminals of these cells. (ijbs.com)
  • responses
  • We use optical electrophysiology to directly measure electrical responses in presynaptic terminals and demonstrate that sustained peripheral responses are temporally sharpened by the combined activity of two types of inhibitory GABA receptors to generate contrast-enhanced voltage responses in central OSN axon terminals. (nih.gov)
  • Furthermore, we show how these GABA receptors modulate the time course of innate behavioral responses after odor pulse termination, demonstrating an important role for temporal contrast enhancement in odor-guided navigation. (nih.gov)
  • Whereas GABA A receptors shape PN odor responses during the early phase of odor responses, GABA B receptors mediate odor-evoked inhibition on longer time scales. (jneurosci.org)
  • GABA receptors contribute to odor-evoked inhibition of PNs on both fast and slow time scales, and GABA-mediated slow inhibition increases the diversity of odor-evoked responses among PNs. (jneurosci.org)
  • The multimodal neurons lead to change of behavior and assist in analyzing behavior responses to certain stimulus. (wikipedia.org)
  • single neuron
  • A single neuron typically has several inputs (dendrites) or sensors, a relatively long cord (axon) which typically branches many times, and has several outputs connecting to other neurons or muscle tissue. (wikipedia.org)
  • This situation is partly the result of the many different experimental settings, and the difficulty to separate the intrinsic properties of a single neuron from measurements effects and interactions of many cells (network effects). (wikipedia.org)
  • bipolar
  • For example, cochlear hair cells, retinal receptor cells, and retinal bipolar cells do not spike. (wikipedia.org)
  • The chemical reaction begins with the photoreceptor sending a message to a neuron called the bipolar cell through the use of an action potential, or nerve impulse. (wikipedia.org)
  • The five basic classes of neurons within the retina are photoreceptor cells, bipolar cells, ganglion cells, horizontal cells, and amacrine cells. (wikipedia.org)
  • The basic circuitry of the retina incorporates a three-neuron chain consisting of the photoreceptor (either a rod or cone), bipolar cell, and the ganglion cell. (wikipedia.org)
  • stimuli
  • Polymodality is the feature of a single receptor of responding to multiple modalities, such as free nerve endings which can respond to temperature, mechanical stimuli (touch, pressure, stretch) or pain (nociception). (wikipedia.org)
  • Different types of sensory neurons have different sensory receptors that respond to different kinds of stimuli. (wikipedia.org)
  • stimulus
  • Firestein S, Picco C and Menini A (1993) The relation between stimulus and response in olfactory receptor cells of the tiger salamander. (els.net)
  • Natural or pharmacological input neuron models - The models in this category connect between the input stimulus which can be either pharmacological or natural, to the probability of a spike event. (wikipedia.org)
  • The type and location of the sensory receptor activated by the stimulus plays the primary role in coding the sensation. (wikipedia.org)
  • Sensory neurons also known as afferent neurons are neurons that convert a specific type of stimulus, via their receptors, into action potentials or graded potentials. (wikipedia.org)
  • Functionally, it is highly possible that adaptation may enhance the limited response range of neurons to encode sensory signals with much larger dynamic ranges by shifting the range of stimulus amplitudes. (wikipedia.org)
  • depolarize
  • This influx of positive ions and efflux of negative ions causes the neuron to depolarize, generating an action potential. (wikipedia.org)
  • After olfactory neurons depolarize in response to an odorant, the G-protein mediated second messenger response activates adenylyl cyclase, increasing cyclic AMP (cAMP) concentration inside a cell, which then opens a cyclic nucleotide gated cation channel. (wikipedia.org)
  • encode
  • Buck L and Axel R (1991) A novel multigene family may encode odorant receptors: a molecular basis for odor recognition. (els.net)
  • Animals with mutations in insulin-related 1 ( ins-1 ), abnormal dauer formation 2 ( daf-2 ), and aging alteration 1 ( age-1 ), which encode the homolog of human insulin, insulin/IGF-1 receptor, and PIP3 kinase, respectively, demonstrated significant deficits in benzaldehyde-starvation associative plasticity. (jneurosci.org)
  • gene
  • Here, we applied calcium imaging to characterize the odorant response properties of single neurons from gene-targeted mice in which the green fluorescent protein is coexpressed with a particular OR. (jneurosci.org)
  • neural
  • Collectively, the results provide evidence for a role of locally regulated retinoid metabolism in neuroprotection and in determining population size of neurons at a late stage of neural circuit formation. (jneurosci.org)
  • In that sense, biological neural models differ from artificial neuron models that do not presume to predict the outcomes of experiments involving the biological neural tissue (although artificial neuron models are also concerned with execution of perception and estimation tasks). (wikipedia.org)
  • Olfactory fatigue is an example of neural adaptation or sensory adaptation. (wikipedia.org)
  • Some key players in several neural systems include Ca2+ions (see Calcium in biology) that send negative feedback in second messenger pathways that allow the neural receptor cells to close or open channels in response to the changes of ion flow. (wikipedia.org)
  • sensilla
  • In addition, the HvirGABA B -R1 specific probe also labelled several cells under shorter olfactory sensilla, but never stained cells under mechanosensory/gustatory sensilla chaetica. (ijbs.com)
  • D , Mean firing rates ( n = 4 flies) of a neuron recorded in ab3 sensilla of ArcLight-expressing flies. (nih.gov)
  • mechanisms
  • However, it remains unclear how mechanisms for temporal contrast enhancement in the olfactory system can enhance the detection of odor plume edges during navigation. (nih.gov)
  • Many molecular factors and cellular mechanisms synergize to ensure that each step, from progenitor proliferation to wiring of immature neurons, is tightly controlled. (springer.com)
  • Ultimately, biological neuron models aim to explain the mechanisms underlying the operation of the nervous system for the purpose of restoring lost control capabilities such as perception (e.g. deafness or blindness), motor movement decision making, and continuous limb control. (wikipedia.org)
  • Depending on the location and identity of the neurons, various mechanisms have been found to underlie ephaptic inhibition. (wikipedia.org)
  • nerve
  • Mind concepts (as in mind vs. body), and cognitive and behavioral aspects, are introduced where they have at least a fairly direct connection to physical aspects of the brain, neurons, spinal cord, nerve networks, neurotransmitters, etc. (wikipedia.org)
  • See also: olfactory receptor neurons Optic nerve (cranial nerve 2) Sight. (wikipedia.org)
  • proteins
  • Receptor function and sensitivity are usually regulated by interaction with accessory proteins. (frontiersin.org)
  • The performance of membrane proteins such as ion channels or receptors is dynamically adjusted according to changing physiological requirements. (frontiersin.org)
  • This family is composed of pheromone binding proteins (PBP), which are male-specific and associate with pheromone-sensitive neurons and general-odorant-binding proteins (GOBP). (wikipedia.org)
  • Functional
  • 1998) Functional expression of a mammalian odorant receptor. (els.net)
  • We provide evidence that RARE-dependent transcription and local homeostatic control of retinoids is required for the maintenance of a population of functional neurons with established projections and that inhibition of retinoid signaling results in postnatal and adult neurodegeneration. (jneurosci.org)
  • Functional consequences of unilateral olfactory deprivation: time course and age sensitivity. (springer.com)
  • adaptation
  • Kurahashi T and Menini A (1997) Mechanism of odorant adaptation in the olfactory receptor cell. (els.net)
  • Olfactory fatigue, also known as odor fatigue or olfactory adaptation, is the temporary, normal inability to distinguish a particular odor after a prolonged exposure to that airborne compound. (wikipedia.org)
  • The influx of Ca2+ ions through this channel triggers olfactory adaptation immediately because Ca2+/calmodulin-dependent protein kinase II or CaMK activation directly represses the opening of cation channels, inactivates adenylyl cyclase, and activates the phosphodiesterase that cleaves cAMP. (wikipedia.org)
  • glia
  • Furthermore, many cells in the nervous system are not classified as neurons but instead are classified as glia. (wikipedia.org)
  • spinal
  • Spinal cord - many neurons originate or terminate in the brain and extend down into the spinal column. (wikipedia.org)
  • The spinal cord itself is a bundle of a vast number of neurons, with a total diameter of about 1/2 inch at the brain, thinning to about 1/4 inch diameter at vertebrae L1. (wikipedia.org)
  • The longest single human neuron currently identified extends from the tip of a toe, well over a meter, up to the spinal cord at L1. (wikipedia.org)
  • Many neurons connect to the brain on one end, with the other end connected to another neuron, with the outside (the brain) junction located within the spinal column. (wikipedia.org)
  • Other neurons bundles which are labeled cranial nerves, connect to the brain on one end, and to locations outside the brain on the other, without having a junction inside the spinal column. (wikipedia.org)
  • signals
  • This perspective discusses the physical limits of chemoreception and gives an overview on the receptor types developed during evolution to detect chemical signals from the outside world of an organism. (frontiersin.org)
  • These signals are refined and controlled by the interactions with other types of neurons in the retina. (wikipedia.org)
  • chemosensory
  • Accordingly, the position and molecular identity of specialized frontonasal epithelia and mesenchyme early in gestation and subsequent inductive interactions specify the genesis and differentiation of peripheral chemosensory and neuroendocrine neurons. (harvard.edu)
  • Mechanism
  • To approach the question if such a mechanism may be realized in the pheromone recognition system of male moths in this study attempts were made to explore if moth's pheromone-responsive cells express a GABA B - receptor. (ijbs.com)
  • Although the mechanism is unknown, it is hypothesized that neurons are ephaptically coupled to the frequencies of the local field potential. (wikipedia.org)
  • A hypothesis or explanation behind the mechanism is "one-way", "master-slave", or "unidirectional synchronization" effect as mathematical and fundamental property of non-linear dynamic systems (oscillators like neurons) to synchronize under certain criteria. (wikipedia.org)
  • The visual system can detect motion both using a simple mechanism based on information from multiple clusters of neurons as well as by aggregate through by integrating multiple cues including contrast, form, and texture. (wikipedia.org)
  • system
  • Olfactory receptor neurons are the primary sensory cell in a system designed to detect and discriminate between a large and diverse array of chemical ligands called odours. (els.net)
  • Anatomy of the olfactory system. (els.net)
  • An olfactory receptor neuron (ORN), also called an olfactory sensory neuron (OSN), is a transduction cell within the olfactory system. (wikipedia.org)
  • With a 302-neuron nervous system, Caenorhabditis elegans emerges as an excellent invertebrate model for the molecular study of behavioral plasticity. (jneurosci.org)
  • A biological neuron model, also known as a spiking neuron model, is a mathematical description of the properties of certain cells in the nervous system that generate sharp electrical potentials across their cell membrane, roughly one millisecond in duration, as shown in Fig. 1. (wikipedia.org)
  • Spiking neurons are known to be a major signaling unit of the nervous system, and for this reason characterizing their operation is of great importance. (wikipedia.org)
  • It is worth noting that not all the cells of the nervous system produce the type of spike that define the scope of the spiking neuron models. (wikipedia.org)
  • Problems with sensory neurons associated with the auditory system leads to disorders such as: Auditory processing disorder - Auditory information in the brain is processed in an abnormal way. (wikipedia.org)
  • Kenyon
  • elegantly showed that different subsets of MB neurons (the Kenyon cells) interact in a dynamic fashion to form and stabilize associative olfactory memories. (jneurosci.org)
  • ablation
  • Gogos JA, Osborne J, Nemes A, Mendelsohn M and Axel R (2000) Genetic ablation and restoration of the olfactory topographic map. (els.net)