| auditory spatial response areas of single neurons and space representation in the cerebellum of echo locating bats. | using free-field acoustic stimulation conditions, we studied the auditory spatial response areas of 242 cerebellar neurons of eptesicus fuscus. a best frequency stimulus was delivered from a loudspeaker which was moved across the frontal auditory space in order to determine the response center of each cerebellar neuron. at the response center, the neuron had its lowest minimum threshold. the stimulus was then raised 5-15 db above the lowest minimum threshold of each neuron and the spatial respon ... | 1987 | 3620934 |
| pinna position affects the auditory space representation in the inferior colliculus of the fm bat, eptesicus fuscus. | using free-field acoustic stimulus conditions, we studied the auditory space representation in the inferior colliculus (ic) of the big brown bat, eptesicus fuscus, under different pinna positions. stimuli were delivered from a loudspeaker placed 14 cm in front of the bat to determine the best frequency (bf) of an isolated neuron. a bf stimulus was then delivered as the loudspeaker was moved across the frontal auditory space of the bat to locate the response center of the neuron. at the response ... | 1987 | 3610849 |
| connectional basis for frequency representation in the nuclei of the lateral lemniscus of the bat eptesicus fuscus. | to study the role of the lateral lemniscus as a link in the ascending auditory pathway, injections of neuronal tracers were placed in the anteroventral cochlear nucleus (avcn) and in the inferior colliculus of the bat eptesicus fuscus. to correlate the anatomical results with tonotopic organization, the characteristic frequency of cells at each injection site was determined electrophysiologically. pathways from avcn diverge to 3 major targets in the lateral lemniscus, the intermediate nucleus an ... | 1986 | 3020188 |
| accuracy of distance measurement in the bat eptesicus fuscus: theoretical aspects and computer simulations. | behavioral experiments of simmons [j. acoust. soc. am. 54, 157-173 (1973) and science 204, 1336-1338 (1979)] on the ranging accuracy in the bat eptesicus fuscus have led to far-reaching postulates on the existence of optimal and phase-conserving processing mechanisms in the bat. in this paper, the results of computer simulations of these experiments are presented. two receiver types are investigated: the fully coherent cross-correlation receiver and the cross-correlation receiver with envelope p ... | 1986 | 3950192 |
| phase evaluation in hypothetical receivers simulating ranging in bats. | echo delay discrimination by the bat eptesicus fuscus had been investigated in an experiment with simulated targets jittering in range (simmons 1979). the dip in the resulting psychometric curve was used by simmons to suggest the neuronal implementation of a coherent cross-correlation receiver in the auditory system of bats. by computer simulation it is shown here that the dip may be even more pronounced and less susceptible to noise with alternative receiver configurations which not necessarily ... | 1986 | 3755621 |
| sonar tracking of horizontally moving targets by the big brown bat eptesicus fuscus. | when following a moving target, echolocating bats (eptesicus fuscus) keep their heads aimed at the target's position. this tracking behavior seems not to involve predicting the target's trajectory, but is achieved by the bat's pointing its head at the target's last known position. the bat obtains frequent position updates by emitting sonar signals at a high rate. after the lag between head and target positions and the nonunity tracking gain were corrected for, bats' tracking accuracy in the hori ... | 1985 | 4001947 |
| bat rabies in alberta 1979-1982. | the infection rate among eight species of bats submitted for rabies diagnosis in alberta during 1979-82 was 4.6%. prevalence of rabies was greatest (24%) for hoary bats lasiurus cinereus, while the big brown bat eptesicus fuscus was the species in which rabies was most commonly diagnosed, and the species submitted most frequently for rabies diagnosis was the little brown bat myotis lucifugus. the rabies infection rate among male hoary bats was significantly greater than in either sex of all othe ... | 1985 | 17422507 |
| automatic gain control in the bat's sonar receiver and the neuroethology of echolocation. | the sensitivity of the echolocating bat, eptesicus fuscus, to sonar echoes at different time delays after sonar emissions was measured in a two-choice echo detection experiment. since echo delay is perceptually equivalent to target range, the experiment effectively measured sensitivity to targets at different ranges. the bat's threshold for detecting sonar echoes at a short delay of only 1.0 msec after emissions (corresponding to a range of 17 cm) was 36 db spl (peak to peak), but the threshold ... | 1984 | 6502201 |
| auditory space representation in the superior colliculus of the big brown bat, eptesicus fuscus. | the auditory response areas of 123 superior collicular (sc) units of eptesicus fuscus were studied under free-field acoustic stimulus conditions. a stimulus was delivered from a loudspeaker placed 14 cm in front of a bat. the best frequency of a unit was determined by changing the stimulus frequency until the minimum threshold was measured. a best frequency stimulus was then delivered as the loud-speaker was moved across the auditory space to determine the response center of the auditory respons ... | 1984 | 6498487 |
| preference of a revolving target to a stationary one by the big brown bat, eptesicus fuscus. | utilizing a three-ramp platform, we studied the detection of a revolving and a stationary target in the presence of background clutter by trained eptesicus fuscus. during the test, the mean amplitude of echo from either target was always larger than that of the background echoes at the bat-to-target distance of 30, 70 and 100 cm. the amplitude of the echo reflected back from a revolving target was modulated between a maximum and a minimum value. an electric motor was used to revolve a target. th ... | 1984 | 6571589 |
| pinna orientation determines the maximal directional sensitivity of bat auditory neurons. | the auditory response areas of 192 inferior collicular neurons (ic) of eptesicus fuscus were studied under free field acoustic stimulation. the boundary of the auditory response area of a neuron expands with stimulus intensity (fig. 1). however, there is a response center within each neuron's response area at which the neuron has the maximal sensitivity. all response centers of the 192 neurons are located within a limited space of the bat's contralateral auditory space. the position of the respo ... | 1984 | 6733486 |
| neurons in the superior colliculus of echo-locating bats respond to ultrasonic signals. | using conventional electrophysiological techniques, we demonstrate that neurons in the superior colliculus of the big brown bat (eptesicus fuscus) respond to ultrasonic signals. most response properties of these neurons are very similar to neurons of the inferior colliculus in the same bat. | 1983 | 6626974 |
| unmasking in neurons of the inferior colliculus of eptesicus fuscus with binaural stimulation. | 171 single inferior colliculus neurons displaying basic auditory properties similar to those described previously were sampled, and 118 of those were tested to determine whether monaurally masked responses (band passed noise of +/- 5 khz around the best frequency of the pure tone) could be recovered if the masking noise was presented binaurally. 26% of the units tested showed such an improvement in signal detection, i.e. what is called masking level difference (mld) by psychoacousticians. signal ... | 1983 | 6874604 |
| a comparison of milk composition in myotis lucifugus and eptesicus fuscus (chiroptera: vespertilionidae). | milk composition in two species of insectivorous bats (myotis lucifugus and eptesicus fuscus) was determined. no significant differences in fat, lactose, protein, or energy content were evident during the lactation period for m. lucifugus. the percentage of fat, lactose, and protein averaged 13.5, 3.3, 7.4, respectively, for m. lucifugus, and 16.4, 2.5, 6.2, respectively, for e. fuscus. energy content of milk averaged 7.32 kj/g for m. lucifugus and 8.37 kj/g for e. fuscus. the percentage of lact ... | 1983 | 6830940 |
| biochemical and morphometric studies of heart, liver and skeletal muscle from the hibernating, arousing and aroused big brown bat, eptesicus fuscus. | heart, liver, pectoralis major, and plasma of hibernating, arousing and aroused bats were studied. the activities of four mitochondrial enzymes and three morphometric parameters of mitochondria did not change in the heart. mitochondrial enzyme activities in the liver and pectoralis major did not change. lactate dehydrogenase activity and isoenzyme content in heart, liver and pectoralis major did not change. heart lipid content determined morphometrically decreased transiently after 30 min arousa ... | 1983 | 6641165 |
| maseria vespertilionis n.g., n.sp. (dorylaimina : muspiceidae), a nematode from nearctic bats (vespertilionidae). | maseria vespertilionis n. g., n. sp. (dorylaimina : muspiceidae) is described from nearctic bats (vespertilionidae). in addition to the type host, eptesicus fuscus (p. de beauvois), in oregon, m. vespertilionis was recorded from myotis volans (allen) in oregon, and from m. lucifugus (le conte) in oregon and alaska. the nematode was found only in subcutaneous tissues near the plantar surface of the rear feet of the host. the genus maseria is distinguished from other genera in muspiceidae by vario ... | 1983 | 6638790 |
| bats in the belfry: an outbreak of histoplasmosis. | the belfry and attic of a 100-year-old school building located in central illinois were infested with a colony of big brown bats (eptesicus fuscus). during the week of april 14, 1980, four workers disturbed the piles of bat droppings in the attic, causing dust to become airborne. seven to 10 days later, all four workers developed symptoms and chest x-ray findings compatible with acute pulmonary histoplasmosis. their sera had complement fixation (cf) titers of greater than or equal to 1:32 with f ... | 1982 | 7137434 |
| echolocation in bats: the external ear and perception of the vertical positions of targets. | echolocating bats (eptesicus fuscus) can perceive changes of as little as 3 degrees of arc in the vertical angles separating pairs of horizontal rods. this acuity depends upon modification of sounds entering the external ear canal by the structures of the external ear. deflection of the tragus degrades the acuity of vertical-angle perception from 3 degrees to about 12 degrees to 14 degrees. the pinna-tragus structure produces a strong secondary echo of sounds entering the external ear canal, and ... | 1982 | 7123247 |
| concentrations of lactate and pyruvate and temperature effects on lactate dehydrogenase activity in the tissues of the big brown bat (eptesicus fuscus) during arousal from hibernation. | 1. the rectal temperatures, steady state concentrations of lactate and pyruvate, and the ldh isoenzyme composition in the heart, liver, and pectoral muscle of hibernating and arousing eptesicus fuscus were measured. 2. bat rectal temperature increased from 8.86 to 33.1 degrees c during arousal. 3. during arousal, steady state concentrations of pyruvate and lactate increased significantly in the tissues, however they remained generally below the level necessary to saturate ldh at the respective t ... | 1982 | 7151414 |
| a mathematical model describing the effect of temperature and substrate concentration on the activities of m4 and h4 lactate dehydrogenase from the big brown bat (eptesicus fuscus). | | 1981 | 7325684 |
| neurons in the cerebellum of echolocating bats respond to acoustic signals. | single neurons responding to auditory stimuli (40 msec duration, 0.5 msec rise-decay time) could be isolated from rather large areas of the cerebellar vermis and hemispheres of an echolocating bat, eptesicus fuscus. these neurons had latencies between 4 and 13 msec and best frequencies between 22 and 77 khz. the q10-db values of their tuning curves were between 1.4 and 16.6. when acoustic stimuli were delivered though the earphones, tuning curves measured from each ear alone were nearly identica ... | 1980 | 7397541 |
| perception of echo phase information in bat sonar. | echolocating bats (eptesicus fuscus) can detect changes as small as 500 nanoseconds in the arrival time of sonar echoes when these changes appear as jitter or alternations in arrival time from one echo to the next. the psychophysical function relating the bat's performance to the magnitude of the jitter corresponds to the half-wave rectified cross-correlation function between the emitted sonar signals and the echoes. the bat perceives the phase or period structure of the sounds, which cover the ... | 1979 | 451543 |
| ultrastructure of the atrioventricular node of the big brown bat, eptesicus fucus. | this investigation describes the ultrastructure of the atrioventricular node of eptesicus fuscus. two conducting cells types (nodal and transitional) are indentified which differ in location, myofibrillar content, and types of intercellular junctions. centrally located nodal cells display variable staining intensity and contain disorganized myofibrils which rarely form sarcomeres. desmosomes and nexus-like junctions connect the nodal cells. transitional cells, situated peripherally, exhibit dist ... | 1979 | 532545 |
| echo detection and target-ranging neurons in the auditory system of the bat eptesicus fuscus. | some of the neurons in the nucleus intercollicularis and auditory cortex of the echolocating bat eptesicus fuscus respond selectively to sonar echoes occurring with specific echo delays or pulse-echo intervals. they do not respond for a wide range of other types of sounds or for sonar echoes at longer or shorter pulse-echo intervals; they may, therefore, be specialized for detection and ranging of sonar targets. | 1978 | 705350 |
| canine tooth wear in captive big brown bats (eptesicus fuscus). | | 1976 | 1003049 |
| organochlorine residues in three bat species from four localities in maryland and west virginia, 1973. | in 1973, 119 bats of three species were collected from four localities in maryland and west virginia. the collection included 43 big brown bats (eptesicus fuscus), 43 little brown brown bats (myotis lucifugus), and 33 eastern pipistrelles (pipistrellus subflavus). the bats were collected from round top mountain, washington co., md.; trout cave, pendleton co., w. va.; montpelier barn, prince georges co., md. residues of sigmaddt were highest in carcasses of bats from round top mountain, which is ... | 1976 | 826874 |
| comparison of regional blood distribution in eptesicus fuscus (big brown bat) during torpor (summer), hibernation (winter), and arousal. | | 1975 | 1116073 |
| response at fifteen weeks of the big brown bat (eptesicus fuscus) to intraperitoneal injections of n-2-acetylaminofluorene. | | 1974 | 4472289 |
| reproduction, growth, and mortality of the vespertilionid bat, eptesicus fuscus, in kansas. | | 1974 | 4819591 |
| brightness discrimination thresholds in the bat, eptesicus fuscus. | | 1974 | 4462692 |
| populations and distribution of steatonyssus occidentalis (ewing) (acarina: macronyssidae) infesting the big brown bat, eptesicus fuscus (chiroptera: vespertilionidae). | | 1973 | 4779927 |
| sequential changes in regional distribution of blood in eptesicus fuscus (big brown bat) during arousal from hibernation. | | 1973 | 4779820 |
| metabolized energy of the big brown bat eptesicus fuscus (chiroptera). | | 1973 | 4145443 |
| fluctuations in the preoptic-anterior hypothalamic temperature in the bat, eptesicus fuscus. | | 1971 | 4400037 |
| echolocation in bats: signal processing of echoes for target range. | echolocating bats eptesicus fuscus and phyllostomus hastatus can discriminate between the nearer and farther of two targets. their errors in discrimination are predicted accurately by the autocorrelation functions of their sonar cries. these bats behave as though they have an ideal sonar system which cross correlates the transmitted cry with the returning echo to extract targetrange information. | 1971 | 5541661 |
| echolocation: discrimination of targets by the bat, eptesicus fuscus. | | 1971 | 5548872 |
| transit time of food through the digestive tract of the bat, eptesicus fuscus. | | 1971 | 5147598 |
| fine structure of the pancreatic islet cells of normal and alloxan treated bats (eptesicus fuscus). | | 1970 | 4905599 |
| hearing and cochlear microphonic potentials in the bat eptesicus fuscus. | | 1967 | 6035688 |
| use of big brown bats (eptesicus fuscus) in biomedical research. | | 1966 | 4225475 |
| hearing sensitivity in bats. | absolute hearing thresholds for two bats were determined by an operant conditioning technique. pure tones rangingfrom 2.5 to 100 kilocycles per second were perceived by a single eptesicus fuscus. its maximum sensitivity was on the order of 68 decibles below 1 dyne per square centimeter and occurred at 20 kc/ sec. maximum sensitivity for a single myotis lucifugus was about 64 db below 1 dyne/ cm2 and occurred at 40 kc/ sec. the myotis clearly heard a tone of120 kc/ sec but gave no evidence of hea ... | 1965 | 5852976 |
| parasites from the big brown bat, eptesicus fuscus (beauvois), in western maryland (acarina and siphonaptera). | | 1965 | 14280484 |
| bats: sensitivity to ddt. | big brown bats, eptesicus fuscus, were fed single doses of varying amounts of ddt in corn oil injected into meal worms. all the doses of ddt fed to the bats, 40 milligrams or more per kilogram of body weight, were lethal. within a few hours to 13 days after being dosed, the animals developed convulsions; some bats survived up to 3 days after the oniset of the symptoms of poisoning. bats appear to be far more sensitive to ddt than any other mammal yet tested. | 1964 | 14199722 |
| brown fat: thermogenic effect during arousal from hibernation in the bat. | in the bat eptesicus fuscus the temperature of brown fat exceeded that of other tissues by about 3 degrees c during the late stages of arousal from hibernation. heat production seems to be a major function of brown fat in the hibernating mammal. | 1963 | 13989313 |
| a trypanosome from the big brown bat, eptesicus fuscus fuscus (beauvois), in minnesota. | | 1955 | 13272117 |
| a persistently infecting coronavirus in hibernating myotis lucifugus, the north american little brown bat. | bats are important reservoir hosts for emerging viruses, including coronaviruses that cause diseases in people. although there have been several studies on the pathogenesis of coronaviruses in humans and surrogate animals, there is little information on the interactions of these viruses with their natural bat hosts. we detected a coronavirus in the intestines of 53/174 hibernating little brown bats (myotis lucifugus), as well as in the lungs of some of these individuals. interestingly, the prese ... | 2017 | 28840816 |
| energy conserving thermoregulatory patterns and lower disease severity in a bat resistant to the impacts of white-nose syndrome. | the devastating bat fungal disease, white-nose syndrome (wns), does not appear to affect all species equally. to experimentally determine susceptibility differences between species, we exposed hibernating naïve little brown myotis (myotis lucifugus) and big brown bats (eptesicus fuscus) to the fungus that causes wns, pseudogymnoascus destructans (pd). after hibernating under identical conditions, pd lesions were significantly more prevalent and more severe in little brown myotis. this species di ... | 2017 | 28597237 |
| the phylogeography of myotis bat-associated rabies viruses across canada. | as rabies in carnivores is increasingly controlled throughout much of the americas, bats are emerging as a significant source of rabies virus infection of humans and domestic animals. knowledge of the bat species that maintain rabies is a crucial first step in reducing this public health problem. in north america, several bat species are known to be rabies virus reservoirs but the role of bats of the myotis genus has been unclear due to the scarcity of laboratory confirmed cases and the challeng ... | 2017 | 28542160 |
| first report of bats (mammalia: chiroptera) from the gray fossil site (late miocene or early pliocene), tennessee, usa. | thousands of vertebrate fossils have been recovered from the gray fossil site, tennessee, dating to the miocene-pliocene boundary. among these are but eight specimens of bats representing two different taxa referable to the family vespertilionidae. comparison of the fossils with neogene and quaternary bats reveals that seven of the eight specimens pertain to a species of eptesicus that cannot be distinguished from recent north american eptesicus fuscus. the remaining specimen, a horizontal ramus ... | 2017 | 28462055 |
| dynamic echo information guides flight in the big brown bat. | animals rely on sensory feedback from their environment to guide locomotion. for instance, visually guided animals use patterns of optic flow to control their velocity and to estimate their distance to objects (e.g., srinivasan et al., 1991, 1996). in this study, we investigated how acoustic information guides locomotion of animals that use hearing as a primary sensory modality to orient and navigate in the dark, where visual information is unavailable. we studied flight and echolocation behavio ... | 2016 | 27199690 |
| tight coordination of aerial flight maneuvers and sonar call production in insectivorous bats. | echolocating bats face the challenge of coordinating flight kinematics with the production of echolocation signals used to guide navigation. previous studies of bat flight have focused on kinematics of fruit and nectar-feeding bats, often in wind tunnels with limited maneuvering, and without analysis of echolocation behavior. in this study, we engaged insectivorous big brown bats in a task requiring simultaneous turning and climbing flight, and used synchronized high-speed motion-tracking camera ... | 2015 | 26582935 |
| bats coordinate sonar and flight behavior as they forage in open and cluttered environments. | echolocating bats use active sensing as they emit sounds and listen to the returning echoes to probe their environment for navigation, obstacle avoidance and pursuit of prey. the sensing behavior of bats includes the planning of 3d spatial trajectory paths, which are guided by echo information. in this study, we examined the relationship between active sonar sampling and flight motor output as bats changed environments from open space to an artificial forest in a laboratory flight room. using hi ... | 2014 | 25394632 |
| temporal binding of neural responses for focused attention in biosonar. | big brown bats emit biosonar sounds and perceive their surroundings from the delays of echoes received by the ears. broadcasts are frequency modulated (fm) and contain two prominent harmonics sweeping from 50 to 25 khz (fm1) and from 100 to 50 khz (fm2). individual frequencies in each broadcast and each echo evoke single-spike auditory responses. echo delay is encoded by the time elapsed between volleys of responses to broadcasts and volleys of responses to echoes. if echoes have the same spectr ... | 2014 | 25122915 |
| animal communication: keep your wings off my food! | when foraging, male big brown bats produce ultrasonic social calls. the calls repel rival bats from the caller and its prey, and increase the caller's foraging success during their high-speed aerial excursions. | 2014 | 24735855 |
| encoding of head direction by hippocampal place cells in bats. | most theories of navigation rely on the concept of a mental map and compass. hippocampal place cells are neurons thought to be important for representing the mental map; these neurons become active when the animal traverses a specific location in the environment (the "place field"). head-direction cells are found outside the hippocampus, and encode the animal's head orientation, thus implementing a neural compass. the prevailing view is that the activity of head-direction cells is not tuned to a ... | 2014 | 24431464 |
| bats use a neuronally implemented computational acoustic model to form sonar images. | this paper reexamines neurophysiological results from echolocating big brown bats to propose a new perspective on fm biosonar processing in the auditory system. individual auditory neurons are frequency-tuned and respond to brief, 2-10 ms fm sweeps with an average of one spike per sound to register their tuned frequencies, to detect echo arrival, or to register a local null in the echo spectrum. when initiated by the broadcast, these responses comprise a cascade of single spikes distributed acro ... | 2012 | 22436892 |
| a novel coding mechanism for social vocalizations in the lateral amygdala. | the amygdala plays a central role in evaluating the significance of acoustic signals and coordinating the appropriate behavioral responses. to understand how amygdalar responses modulate auditory processing and drive emotional expression, we assessed how neurons respond to and encode information that is carried within complex acoustic stimuli. we characterized responses of single neurons in the lateral nucleus of the amygdala to social vocalizations and synthetic acoustic stimuli in awake big br ... | 2012 | 22090463 |
| bats use echo harmonic structure to distinguish their targets from background clutter. | when echolocating big brown bats fly in complex surroundings, echoes arriving from irrelevant objects (clutter) located to the sides of their sonar beam can mask perception of relevant objects located to the front (targets), causing "blind spots." because the second harmonic is beamed more weakly to the sides than the first harmonic, these clutter echoes have a weaker second harmonic. in psychophysical experiments, we found that electronically misaligning first and second harmonics in echoes (to ... | 2011 | 21798949 |
| patterns of tropomyosin and troponin-t isoform expression in jaw-closing muscles of mammals and reptiles that express masticatory myosin. | we recently reported that masticatory ('superfast') myosin is expressed in jaw-closing muscles of some rodent species. most mammalian limb muscle fibers express tropomyosin-β (tm-β), along with fast-type or slow-type tropomyosin-β (tm-β), but jaw-closing muscle fibers in members of carnivora express a unique isoform of tm [tm-masticatory (tm-m)] and little or no tm-β. the goal of this study was to determine patterns of tm and troponin-t (tnt) isoform expression in the jaw-closing muscles of rode ... | 2011 | 21389191 |
| perception of echo delay is disrupted by small temporal misalignment of echo harmonics in bat sonar. | echolocating big brown bats emit ultrasonic frequency-modulated (fm) biosonar sounds containing two prominent downward-sweeping harmonics (fm1 and fm2) and perceive target distance from echo delay. in naturally occurring echoes, fm1 and fm2 are delayed by the same amount. even though echoes from targets located off-axis or far away are lowpass filtered, which weakens fm2 relative to fm1, their delays remain the same. we show here that misalignment of fm2 with fm1 by only 2.6 μs is sufficient to ... | 2011 | 21228198 |
| dynamics of hippocampal spatial representation in echolocating bats. | the "place fields" of hippocampal pyramidal neurons are not static. for example, upon a contextual change in the environment, place fields may "remap" within typical timescales of ~ 1 min. a few studies have shown more rapid dynamics in hippocampal activity, linked to internal processes, such as switches between spatial reference frames or changes within the theta cycle. however, little is known about rapid hippocampal place field dynamics in response to external, sensory stimuli. here, we studi ... | 2011 | 20014379 |
| tone-specific and nonspecific plasticity of inferior colliculus elicited by pseudo-conditioning: role of acetylcholine and auditory and somatosensory cortices. | experience-dependent plasticity in the central sensory systems depends on activation of both the sensory and neuromodulatory systems. sensitization or nonspecific augmentation of central auditory neurons elicited by pseudo-conditioning with unpaired conditioning tonal (cs) and unconditioned electric leg (us) stimuli is quite different from tone-specific plasticity, called best frequency (bf) shifts, of the neurons elicited by auditory fear conditioning with paired cs and us. therefore the neural ... | 2009 | 19474174 |
| tone-specific and nonspecific plasticity of the auditory cortex elicited by pseudoconditioning: role of acetylcholine receptors and the somatosensory cortex. | experience-dependent plastic changes in the central sensory systems are due to activation of both the sensory and neuromodulatory systems. nonspecific changes of cortical auditory neurons elicited by pseudoconditioning are quite different from tone-specific changes of the neurons elicited by auditory fear conditioning. therefore the neural circuit evoking the nonspecific changes must also be different from that evoking the tone-specific changes. we first examined changes in the response properti ... | 2008 | 18596186 |
| corticofugal modulation of the paradoxical latency shifts of inferior collicular neurons. | the central auditory system creates various types of neurons tuned to different acoustic parameters other than a specific frequency. the response latency of auditory neurons typically shortens with an increase in stimulus intensity. however, approximately 10% of collicular neurons of the little brown bat show a "paradoxical latency-shift (pls)": long latencies to intense sounds but short latencies to weak sounds. these neurons presumably are involved in the processing of target distance informat ... | 2008 | 18596179 |
| response properties and location of neurons selective for sinusoidal frequency modulations in the inferior colliculus of the big brown bat. | most animal vocalizations, including echolocation signals used by bats, contain frequency-modulated (fm) components. previous studies have described a class of neurons in the inferior colliculus (ic) of the big brown bat that respond exclusively to sinusoidally frequency modulated (sfm) signals and fail to respond to pure tones, noise, amplitude-modulated tones, or single fm sweeps. the aims of this study were to further characterize these neurons' response properties and to determine whether th ... | 2007 | 17634338 |
| acoustic mimicry in a predator-prey interaction. | mimicry of visual warning signals is one of the keystone concepts in evolutionary biology and has received substantial research attention. by comparison, acoustic mimicry has never been rigorously tested. visualizing bat-moth interactions with high-speed, infrared videography, we provide empirical evidence for acoustic mimicry in the ultrasonic warning sounds that tiger moths produce in response to echolocating bats. two species of sound-producing tiger moths were offered successively to naïve, ... | 2007 | 17517637 |
| serotonergic modulation of plasticity of the auditory cortex elicited by fear conditioning. | in the awake big brown bat, 30 min auditory fear conditioning elicits conditioned heart rate decrease and long-term best frequency (bf) shifts of cortical auditory neurons toward the frequency of the conditioned tone; 15 min conditioning elicits subthreshold cortical bf shifts that can be augmented by acetylcholine. the fear conditioning causes stress and an increase in the cortical serotonin (5-ht) level. serotonergic neurons in the raphe nuclei associated with stress and fear project to the ce ... | 2007 | 17475799 |
| effects of agonists and antagonists of nmda and ach receptors on plasticity of bat auditory system elicited by fear conditioning. | in big brown bats, tone-specific plastic changes [best frequency (bf) shifts] of cortical and collicular neurons can be evoked by auditory fear conditioning, repetitive acoustic stimuli or cortical electric stimulation. it has been shown that acetylcholine (ach) plays an important role in evoking large long-term cortical bf shifts. however, the role of n-methyl-d-aspartate (nmda) receptors in evoking bf shifts has not yet been studied. we found 1) nmda applied to the auditory cortex (ac) or infe ... | 2005 | 16061490 |
| corticofugal feedback for collicular plasticity evoked by electric stimulation of the inferior colliculus. | focal electric stimulation of the auditory cortex, 30-min repetitive acoustic stimulation, and auditory fear conditioning each evoke shifts of the frequency-tuning curves [hereafter, best frequency (bf) shifts] of cortical and collicular neurons. the short-term collicular bf shift is produced by the corticofugal system and primarily depends on the relationship in bf between a recorded collicular and a stimulated cortical neuron or between the bf of a recorded collicular neuron and the frequency ... | 2005 | 16000518 |
| lateral inhibition for center-surround reorganization of the frequency map of bat auditory cortex. | repetitive acoustic stimulation, auditory fear conditioning, and focal electric stimulation of the auditory cortex (ac) each evoke the reorganization of the central auditory system. our current study of the big brown bat indicates that focal electric stimulation of the ac evokes center-surround reorganization of the frequency map of the ac. in the center, the neuron's best frequencies (bfs), together with their frequency-tuning curves, shift toward the bfs of electrically stimulated cortical neu ... | 2004 | 15548634 |
| evaluation of an auditory model for echo delay accuracy in wideband biosonar. | in a psychophysical task with echoes that jitter in delay, big brown bats can detect changes as small as 10-20 ns at an echo signal-to-noise ratio of approximately 49 db and 40 ns at approximately 36 db. this performance is possible to achieve with ideal coherent processing of the wideband echoes, but it is widely assumed that the bat's peripheral auditory system is incapable of encoding signal waveforms to represent delay with the requisite precision or phase at ultrasonic frequencies. this ass ... | 2003 | 14514218 |
| development of reorganization of the auditory cortex caused by fear conditioning: effect of atropine. | reorganization of the frequency map in the central auditory system is based on shifts in the best frequencies (bfs; hereafter, bf shifts), together with the frequency-response curves, of auditory neurons. in the big brown bat, conditioning with acoustic stimulation followed by electric leg-stimulation causes bf shifts of collicular and cortical neurons. the collicular bf shift develops quickly and is short term, whereas the cortical bf shift develops slowly and is long term. the acetycholine lev ... | 2003 | 12966181 |
| neural measurement of sound duration: control by excitatory-inhibitory interactions in the inferior colliculus. | in the inferior colliculus (ic) of the big brown bat, a subpopulation of cells ( approximately 35%) are tuned to a narrow range of sound durations. band-pass tuning for sound duration has not been seen at lower levels of the auditory pathway. previous work suggests that it arises at the ic through the interaction of sound-evoked, temporally offset, excitatory and inhibitory inputs. to test this hypothesis, we recorded from duration-tuned neurons in the ic and examined duration tuning before and ... | 2000 | 10980020 |
| corticofugal modulation of the midbrain frequency map in the bat auditory system. | the auditory system, like the visual and somatosensory systems, contains topographic maps in its central neural pathways. these maps can be modified by sensory deprivation, injury and experience in both young and adult animals. such plasticity has been explained by changes in the divergent and convergent projections of the ascending sensory system. another possibility, however, is that plasticity may be mediated by descending corticofugal connections. we have investigated the role of descending ... | 1998 | 10195109 |
| arctiid moths and bat echolocation: broad-band clicks interfere with neural responses to auditory stimuli in the nuclei of the lateral lemniscus of the big brown bat. | clicks emitted by arctiid moths interfere with the ranging ability of echolocating bats. to identify possible neural correlates of this interference, we recorded responses of single units in the nuclei of the lateral lemniscus to combinations of a broad-band click and a test signal (pure tones or frequency-modulated sweeps). in 77% of 87 units tested, clicks interfered with neural responses to the test stimuli. the interference fell into two categories: latency ambiguity and suppression. units s ... | 1998 | 9463919 |
| temporal integration in the echolocating bat, megaderma lyra. | temporal integration is a crucial feature of auditory temporal processing. we measured the psychophysical temporal integration of acoustic intensity in the echolocating bat megaderma lyra using a two-alternative forced-choice procedure. a measuring paradigm was chosen in which the absolute threshold for pairs of short tone pips was determined as a function of the temporal separation between the pips. the time constants determined with this paradigm are a crucial characteristic of the sonar syste ... | 1996 | 8951448 |
| delay-tuned neurons in the midbrain of the big brown bat. | 1. the auditory midbrain in eptesicus contains delay-tuned neurons that encode target range. most delay-tuned neurons respond poorly to tones or individual frequency-modulated (fm) sweeps and require combinations of fm sweeps. they are combination sensitive and delay tuned. the index of facilitation (if), a coefficient measuring combination sensitivity for individual delay-tuned neurons, ranged from 0.14 to 1.0, with an average of 0.64 +/- 0.24 (mean +/- sd). of the 33 facilitated responses from ... | 1995 | 7608757 |
| a possible neuronal basis for representation of acoustic scenes in auditory cortex of the big brown bat. | behavioural studies and field observations demonstrate that echolocating bats simultaneously perceive range, direction and shape of multiple objects in the environment as acoustic images derived from echoes. cortical echo delay-tuned neurons contribute to the perception of object range, because focal inactivation of these neurons disrupts behavioural discrimination of range. we report here that response properties of delay-tuned neurons in the cortical tonotopic area of the bat, eptesicus, trans ... | 1993 | 8350920 |
| the effect of roost sealing as a method to control maternity colonies of big brown bats. | | 2013 | 3828940 |
| characteristics of bat rabies in alberta. | rabies in bats was monitored in alberta from 1971 to 1978 big brown bats replaced silver-haired bats as the species most frequently reported rabid during these years. rabies infection was comparatively high among little brown bats in central alberta in 1973 and has subsequently declined. only one rabid little brown bat was discovered in southern alberta which is populated by a different subspecies. outbreaks of rabies in little brown and big brown bat colonies tended to be brief events. observat ... | 1980 | 7397600 |
| studies of arthropod-borne virus infections in chiroptera. v. characteristics of lines of japanese b encephalitis virus developed by serial passage in big brown bats (eptesicus f. fuscus) maintained at different environmental temperatures. | | 1969 | 5764191 |
| survey of parasitic bacteria in bat bugs, colorado. | bat bugs (cimex adjunctus barber) (hemiptera: cimicidae) collected from big brown bats (eptesicus fuscus palisot de beauvoir) in colorado, united states were assessed for the presence of bartonella, brucella, and yersinia spp. using molecular techniques. no evidence of brucella or yersinia infection was found in the 55 specimens collected; however, 4/55 (7.3%) of the specimens were positive for bartonella dna. multi-locus characterization of bartonella dna shows that sequences in bat bugs are ph ... | 2018 | 29329460 |
| comparative analysis of landscape effects on spatial genetic structure of the big brown bat and one of its cimicid ectoparasites. | identification of landscape features that correlate with genetic structure permits understanding of factors that may influence gene flow in a species. comparing effects of the landscape on a parasite and host provides potential insights into parasite-host ecology. we compared fine-scale spatial genetic structure between big brown bats (eptesicus fuscus) and their cimicid ectoparasite (cimex adjunctus; class insecta) in the lower great lakes region of the united states, in an area of about 160,00 ... | 2017 | 29075444 |
| protection of bats (eptesicus fuscus) against rabies following topical or oronasal exposure to a recombinant raccoon poxvirus vaccine. | rabies is an ancient neglected tropical disease that causes tens of thousands of human deaths and millions of cattle deaths annually. in order to develop a new vaccine for potential use in bats, a reservoir of rabies infection for humans and animals alike, an in silico antigen designer tool was used to create a mosaic glycoprotein (mog) gene using available sequences from the rabies phylogroup i glycoprotein. this sequence, which represents strains more likely to occur in bats, was cloned into r ... | 2017 | 28976983 |
| echolocating bats rely on audiovocal feedback to adapt sonar signal design. | many species of bat emit acoustic signals and use information carried by echoes reflecting from nearby objects to navigate and forage. it is widely documented that echolocating bats adjust the features of sonar calls in response to echo feedback; however, it remains unknown whether audiovocal feedback contributes to sonar call design. audiovocal feedback refers to the monitoring of one's own vocalizations during call production and has been intensively studied in nonecholocating animals. audiovo ... | 2017 | 28973851 |
| isolation, characterization and prevalence of a novel gammaherpesvirus in eptesicus fuscus, the north american big brown bat. | little is known about the relationship of gammaherpesviruses with their bat hosts. gammaherpesviruses are of interest because of their long-term infection of lymphoid cells and their potential to cause cancer. here, we report the characterization of a novel bat herpesvirus isolated from a big brown bat (eptesicus fuscus) in canada. the genome of the virus, tentatively named eptesicus fuscus herpesvirus (efhv), is 166,748 base pairs. phylogenetically efhv is a member of gammaherpesvirinae, in whi ... | 2018 | 29407381 |
| do bats use guano and urine stains to find new roosts? tests with three group-living bats. | many animals use social cues to find refuges. bats can find roosts using the echolocation and social calls of conspecifics, but they might also use scent cues, a possibility which is less studied. the entrances of bat roosts are often marked by guano and urine, providing possible scent cues. we conducted eight experiments to test whether bats use the scent of guano and urine to find potential roosts. in field experiments, we tested if molossus molossus (velvety free-tailed bats) in panama and ep ... | 2020 | 33047058 |
| winter habitats of bats in texas. | few studies have described winter microclimate selection by bats in the southern united states. this is of particular importance as the cold-adapted fungus, pseudogymnoascus destructans, which causes the fatal bat disease white-nose syndrome (wns), continues to spread into southern united states. to better understand the suitability of winter bat habitats for the growth of p. destructans in this region, we collected roost temperature and vapor pressure deficit from 97 hibernacula in six ecoregio ... | 2019 | 31393965 |
| active acoustic interference elicits echolocation changes in heterospecific bats. | echolocating bats often forage in the presence of both conspecific and heterospecific individuals, which have the potential to produce acoustic interference. recent studies have shown that at least one bat species, the brazilian free-tailed bat (tadarida brasiliensis), produces specialized social signals that disrupt the sonar of conspecific competitors. we herein discuss the differences between passive and active jamming signals and test whether heterospecific jamming occurs in species overlapp ... | 2018 | 29950451 |
| separating the effects of water quality and urbanization on temperate insectivorous bats at the landscape scale. | many local scale studies have shown that bats respond to water quality degradation or urbanization in a species-specific manner. however, few have separated the effects of urbanization versus water quality degradation on bats, in single city or single watershed case studies. across north carolina, usa, we used the standardized north american bat monitoring program mobile transect protocol to survey bat activity in 2015 and 2016 at 41 sites. we collected statewide water quality and urban land cov ... | 2018 | 29321903 |
| binaural response properties and sensitivity to interaural difference of neurons in the auditory cortex of the big brown bat, eptesicus fuscus. | this study examines binaural response properties and sensitivity to interaural level difference of single neurons in the primary auditory cortex (ac) of the big brown bat, eptesicus fuscus under earphone stimulation conditions. contralateral sound stimulation always evoked response from all 306 ac neurons recorded but ipsilateral sound stimulation either excited, inhibited or did not affect their responses. high best frequency (bf) neurons typically had high minimum threshold (mt) and low bf neu ... | 2020 | 31785358 |
| first record of carios kelleyi (acari: ixodida: argasidae) in new jersey, united states and implications for public health. | the soft tick carios kelleyi (cooley and kohls), a parasite of bats known to occur in at least 29 of the 48 conterminous u.s. states, is here reported from new jersey for the first time, based on larvae collected from big brown bats, eptesicus fuscus. although thought to be widespread in north america, the ecology of c. kelleyi is not well understood, despite reports of this species feeding on humans and its consequent potential as a disease vector. the association of c. kelleyi with bat species ... | 2020 | 32901802 |
| seroprevalence in bats and detection of borrelia burgdorferi in bat ectoparasites. | the role of bats in the enzootic cycle of lyme disease and relapsing fever-causing bacteria is a matter of speculation. in canada, borrelia burgdorferi sensu stricto (ss) is the genospecies that is responsible for most cases of lyme disease in humans. in this study, we determined if big brown bats, eptesicus fuscus, have been exposed to spirochetes from the genus borrelia. we collected serum from 31 bats and tested them for the presence of anti-borrelia burgdorferi antibodies using a commercial ... | 2020 | 32244986 |
| using deuterium oxide as a non-invasive, non-lethal tool for assessing body composition and water consumption in mammals. | body condition scoring systems and body condition indices are common techniques used for assessing the health status or fitness of a species. body condition scoring systems are evaluator dependent and have the potential to be highly subjective. body condition indices can be confounded by foraging, the effects of body weight, as well as statistical and inferential problems. an alternative to body condition scoring systems and body condition indices is using a stable isotope such as deuterium oxid ... | 2020 | 32150166 |
| big brown bats are challenged by acoustically-guided flights through a circular tunnel of hoops. | mines and caves provide essential roosting places for bats, but often they are obstructed to prevent entry by humans. to allow bats to access their roosts, metal corrugated culvert pipes are sometimes installed. wildlife surveys indicate, however, that bats may abandon caves having corrugated culvert entrances. culverts may be confusing to bats due to the complex patterns of echoes returned by the regular, ring-like corrugations. we tested the hypothesis that a circular tunnel composed of succes ... | 2020 | 31964933 |
| interferon regulatory factor 3-mediated signaling limits middle-east respiratory syndrome (mers) coronavirus propagation in cells from an insectivorous bat. | insectivorous bats are speculated to be ancestral hosts of middle-east respiratory syndrome (mers) coronavirus (cov). mers-cov causes disease in humans with thirty-five percent fatality, and has evolved proteins that counteract human antiviral responses. since bats experimentally infected with mers-cov do not develop signs of disease, we tested the hypothesis that mers-cov would replicate less efficiently in bat cells than in human cells because of its inability to subvert antiviral responses in ... | 2019 | 30781790 |
| arousal from hibernation and reactivation of eptesicus fuscus gammaherpesvirus (efhv) in big brown bats. | many viruses that cause serious and often fatal disease in humans have spilled over from bats. recent evidence suggests that stress may enhance virus shedding by bats increasing the possibility of transmission to other species. to understand the reasons for spillover is therefore important to determine the molecular pathways that link stress to virus reactivation and shedding in bats. we recently isolated and characterized a gammaherpesvirus (eptesicus fuscus herpesvirus, efhv) autochthonous to ... | 2019 | 30554475 |
| bat rabies in washington state: temporal-spatial trends and risk factors for zoonotic transmission (2000-2017). | rabies is a zoonotic viral disease that can affect all mammals. in the united states, the majority of human rabies cases are caused by bats, which are the only known reservoirs for rabies virus (rabv) in washington state. we sought to characterize bat rabv epidemiology in washington among bats submitted by the public for rabv testing. | 2018 | 30300384 |
| estimation of spatiotemporal trends in bat abundance from mortality data collected at wind turbines. | renewable energy sources, such as wind energy, are essential tools for reducing the causes of climate change, but wind turbines can pose a collision risk for bats. to date, the population-level effects of wind-related mortality have been estimated for only 1 bat species. to estimate temporal trends in bat abundance, we considered wind turbines as opportunistic sampling tools for flying bats (analogous to fishing nets), where catch per unit effort (carcass abundance per monitored turbine) is a pr ... | 2020 | 32424911 |
| a smart curtailment approach for reducing bat fatalities and curtailment time at wind energy facilities. | the development and expansion of wind energy is considered a key global threat to bat populations. bat carcasses are being found underneath wind turbines across north and south america, eurasia, africa, and the austro-pacific. however, relatively little is known about the comparative impacts of techniques designed to modify turbine operations in ways that reduce bat fatalities associated with wind energy facilities. this study tests a novel approach for reducing bat fatalities and curtailment ti ... | 2019 | 30939226 |