scholarly journals Slowly emerging glycinergic transmission enhances inhibition in the sound localization pathway of the avian auditory system

2014 ◽  
Vol 111 (3) ◽  
pp. 565-572 ◽  
Author(s):  
Matthew J. Fischl ◽  
Sonia R. Weimann ◽  
Michael G. Kearse ◽  
R. Michael Burger
Keyword(s):  
Glycine Receptor ◽  
Low Frequency ◽  
Neural Pathways ◽  
Acoustic Stimuli ◽  
Rate Dependent ◽  
Inhibitory Circuitry ◽  
Temporal Features ◽  
Prominent Component ◽  
Inhibitory Transmitter ◽  
Glycinergic Inhibition

Localization of low-frequency acoustic stimuli is processed in dedicated neural pathways where coincidence-detecting neurons compare the arrival time of sound stimuli at the two ears, or interaural time disparity (ITD). ITDs occur in the submillisecond range, and vertebrates have evolved specialized excitatory and inhibitory circuitry to compute these differences. Glycinergic inhibition is a computationally significant and prominent component of the mammalian ITD pathway. However, evidence for glycinergic transmission is limited in birds, where GABAergic inhibition has been thought to be the dominant or exclusive inhibitory transmitter. Indeed, previous work showed that GABA antagonists completely eliminate inhibition in avian nuclei specialized for processing temporal features of sound, nucleus magnocellularis (NM) and nucleus laminaris (NL). However, more recent work shows that glycine is coexpressed with GABA in synaptic terminals apposed to neurons in both nuclei (Coleman WL, Fischl MJ, Weimann SR, Burger RM. J Neurophysiol 105: 2405–2420, 2011; Kuo SP, Bradley LA, Trussell LO. J Neurosci 29: 9625–9634, 2009). Here we show complementary evidence of functional glycine receptor (GlyR) expression in NM and NL. Additionally, we show that glycinergic input can be evoked under particular stimulus conditions. Stimulation at high but physiologically relevant rates evokes a slowly emerging glycinergic response in NM and NL that builds over the course of the stimulus. Glycinergic response magnitude was stimulus rate dependent, representing 18% and 7% of the total inhibitory current in NM and NL, respectively, at the end of the 50-pulse, 200-Hz stimulus. Finally, we show that the glycinergic component is functionally relevant, as its elimination reduced inhibition of discharges evoked by current injection into NM neurons.

Enhancement of neural synchronization in the anteroventral cochlear nucleus. II. Responses in the tuning curve tail

1994 ◽  
Vol 71 (3) ◽  
pp. 1037-1051 ◽  
Author(s):  
P. X. Joris ◽  
P. H. Smith ◽  
T. C. Yin
Keyword(s):  
Cochlear Nucleus ◽  
Tuning Curve ◽  
Phase Locking ◽  
Low Frequency ◽  
Companion Paper ◽  
Acoustic Stimuli ◽  
Anteroventral Cochlear Nucleus ◽  
Temporal Features ◽  
Peripheral Auditory System ◽  
Trapezoid Body

1. Discharges of neurons in the peripheral auditory system contain information about the temporal features of acoustic stimuli. Phase-locking of neurons in the anteroventral cochlear nucleus (AVCN) is usually reported to be less robust than in auditory nerve (AN) fibers, which provide their major input. In a companion paper we reported that some cells in AVCN of the cat show enhanced phase-locking compared with the AN when stimulated at the frequency to which they are most sensitive [characteristic frequency (CF)]. We called neurons "high-sync" when they showed vector strengths (R, a measure of phase-locking) > or = 0.9. Here we report phase-locking properties to stimuli at frequencies below CF. 2. Horseradish peroxidase-filled glass micropipettes or metal microelectrodes were inserted into the trapezoid body (TB), which is the large output tract of the AVCN. Acoustically driven fibers were classified on the basis of the shape of the poststimulus time (PST) histograms to short tone bursts at CF. We then presented low-frequency tones of increasing SPL and determined the maximum R value at 500 Hz (R500) for each fiber. Using the same experimental protocol we studied phase-locking in the ANs of two animals because maximal R values at the tuning curve tail have not been reported for AN fibers. 3. Although phase-locking in AN fibers is usually assumed to be independent of CF, we found that fibers with CF > 2 kHz tended to have higher R500 values than fibers with CF < or = 2 kHz. Moreover, R500 was > or = 0.9 in 20% (42 of 196) of the fibers studied and could be as high as 0.95. This population of fibers was defined as having "high-sync tails" and consisted almost entirely of fibers with low or medium spontaneous rate. 4. High-CF TB fibers stimulated at 500 Hz showed very high phase-locking. High-sync tails (R500 > or = 0.9) were found in 41 of 70 TB fibers. For a subset of these fibers (1/3 in total: 23 of 70) phase-locking was higher than is ever observed in the AN (R500 > or = 0.95); these fibers were defined as showing synchronization "enhancement." Virtually all fibers showing synchronization enhancement had primary-like-with-notch (PLN) PST histograms. Chopper and primary-like fibers showed high-sync tails for CFs > 3 kHz. 5. Synchronization filter functions were obtained for high-CF AN fibers by determining maximum synchronization for a range of stimuli below CF.(ABSTRACT TRUNCATED AT 400 WORDS)

scholarly journals Field assessment of behavioural responses of southern stingrays ( Hypanus americanus ) to acoustic stimuli

2020 ◽  
Vol 7 (1) ◽  
pp. 191544
Author(s):  
Megan F. Mickle ◽  
Rachel H. Pieniazek ◽  
Dennis M. Higgs
Keyword(s):  
Low Frequency ◽  
Free Swimming ◽  
Male And Female ◽  
Behavioural Responses ◽  
Acoustic Stimuli ◽  
Field Assessment ◽  
Rest Time ◽  
Field Setting ◽  
Behavioural Audiogram

The ability of elasmobranchs to detect and use sound cues has been heavily debated in previous research and has only recently received revived attention. To properly understand the importance of sound to elasmobranchs, assessing their responses to acoustic stimuli in a field setting is vital. Here, we establish a behavioural audiogram of free-swimming male and female southern stingrays ( Hypanus americanus ) exposed to low-frequency tones. We demonstrate that female stingrays exposed to tones (50–500 Hz) exhibit significant changes in swimming behaviours (increased time spent swimming, decreased rest time, increased surface breaches and increased side swimming with pectoral flapping) at 140 dB re 1 µPa (−2.08 to −2.40 dB re 1 m s −2 ) while males exposed to the same tones did not exhibit a change in these behaviours until 160 dB re 1 µPa (−1.13 to −1.21 dB re 1 m s −2 ). Our results are the first demonstration of field responses to sound in the Batoidea and show a distinct sensitivity to low-frequency acoustic inputs.

scholarly journals A Novel Glycine Receptor Variant with Startle Disease Affects Syndapin I and Glycinergic Inhibition

2020 ◽  
Vol 40 (25) ◽  
pp. 4954-4969 ◽  
Author(s):  
Georg Langlhofer ◽  
Natascha Schaefer ◽  
Hans M. Maric ◽  
Angelo Keramidas ◽  
Yan Zhang ◽  
...  
Keyword(s):  
Glycine Receptor ◽  
Startle Disease ◽  
Glycinergic Inhibition

Role of Glycinergic Inhibition in Shaping Activity of Saccadic Burst Neurons

2009 ◽  
Vol 101 (6) ◽  
pp. 3063-3074 ◽  
Author(s):  
Yoshiki Iwamoto ◽  
Hitoshi Kaneko ◽  
Kaoru Yoshida ◽  
Hiroshi Shimazu
Keyword(s):  
Inhibitory Action ◽  
Glycine Receptor ◽  
Extracellular Recording ◽  
Single Pulse ◽  
Excitatory Input ◽  
Spontaneous Discharge ◽  
Visual Responses ◽  
Burst Neurons ◽  
Glycinergic Inhibition

The immediate premotor signals for saccades are created at the level of medium-lead burst neurons (MLBNs). During fixations, MLBNs receive tonic inhibition from omnipause neurons (OPNs), which use glycine as a neurotransmitter. To elucidate the role of this inhibition, we studied discharge patterns of horizontal MLBNs following iontophoretic application of strychnine, a glycine-receptor antagonist, in alert cats. Three-barrel micropipettes were used for extracellular recording and iontophoresis. After application of strychnine, MLBNs exhibited spontaneous discharge and visual responses during intersaccadic intervals. Spikes were evoked by single-pulse stimulation of the contralateral superior colliculus (SC). These results show that MLBNs receive substantial excitatory input during intersaccadic intervals and that inhibitory action of OPNs is indeed necessary to prevent MLBNs from firing. Strychnine also affected saccade-related activity of MLBNs. The burst of activity, as in normal conditions, declined rapidly before the end of saccades but was followed by low rate spike activity, which continued beyond the end of saccades. This suggests that in normal conditions, the termination of saccades is determined by resumed inhibitory action of OPNs and not by termination of excitatory input to MLBNs. In addition, the firing rate and the number of spikes during saccades increased after strychnine application, suggesting that MLBNs receive glycinergic inhibition of non-OPN origin as well. We conclude that glycinergic inhibition plays essential roles in the maintenance of stable fixation, the termination of saccades, and the regulation of saccade size and velocity.

Role of GABAergic Inhibition in the Coding of Interaural Time Differences of Low-Frequency Sounds in the Inferior Colliculus

2005 ◽  
Vol 93 (6) ◽  
pp. 3390-3400 ◽  
Author(s):  
W. R. D’Angelo ◽  
S. J. Sterbing ◽  
E.-M. Ostapoff ◽  
S. Kuwada
Keyword(s):  
Inferior Colliculus ◽  
Signal To Noise Ratio ◽  
Interaural Time Difference ◽  
Low Frequency ◽  
Gabaergic Inhibition ◽  
Interaural Time Differences ◽  
Gaba Antagonists ◽  
Inhibitory Transmitter ◽  
Almost All

A major cue for the localization of sound in space is the interaural time difference (ITD). We examined the role of inhibition in the shaping of ITD responses in the inferior colliculus (IC) by iontophoretically ejecting γ-aminobutyric acid (GABA) antagonists and GABA itself using a multibarrel pipette. The GABA antagonists block inhibition, whereas the applied GABA provides a constant level of inhibition. The effects on ITD responses were evaluated before, during and after the application of the drugs. If GABA-mediated inhibition is involved in shaping ITD tuning in IC neurons, then applying additional amounts of this inhibitory transmitter should alter ITD tuning. Indeed, for almost all neurons tested, applying GABA reduced the firing rate and consequently sharpened ITD tuning. Conversely, blocking GABA-mediated inhibition increased the activity of IC neurons, often reduced the signal-to-noise ratio and often broadened ITD tuning. Blocking GABA could also alter the shape of the ITD function and shift its peak suggesting that the role of inhibition is multifaceted. These effects indicate that GABAergic inhibition at the level of the IC is important for ITD coding.

scholarly journals Temporal Features of Spectral Integration in the Inferior Colliculus: Effects of Stimulus Duration and Rise Time

2009 ◽  
Vol 102 (1) ◽  
pp. 167-180 ◽  
Author(s):  
Donald Gans ◽  
Kianoush Sheykholeslami ◽  
Diana Coomes Peterson ◽  
Jeffrey Wenstrup
Keyword(s):  
Inferior Colliculus ◽  
Rise Time ◽  
Low Frequency ◽  
Auditory Pathway ◽  
Spectral Integration ◽  
Auditory Responses ◽  
Temporal Features ◽  
Vocal Signals ◽  
Inhibitory Interactions ◽  
Different Levels

This report examines temporal features of facilitation and suppression that underlie spectrally integrative responses to complex vocal signals. Auditory responses were recorded from 160 neurons in the inferior colliculus (IC) of awake mustached bats. Sixty-two neurons showed combination-sensitive facilitation: responses to best frequency (BF) signals were facilitated by well-timed signals at least an octave lower in frequency, in the range 16–31 kHz. Temporal features and strength of facilitation were generally unaffected by changes in duration of facilitating signals from 4 to 31 ms. Changes in stimulus rise time from 0.5 to 5.0 ms had little effect on facilitatory strength. These results suggest that low frequency facilitating inputs to high BF neurons have phasic-on temporal patterns and are responsive to stimulus rise times over the tested range. We also recorded from 98 neurons showing low-frequency (11–32 kHz) suppression of higher BF responses. Effects of changing duration were related to the frequency of suppressive signals. Signals <23 kHz usually evoked suppression sustained throughout signal duration. This and other features of such suppression are consistent with a cochlear origin that results in masking of responses to higher, near-BF signal frequencies. Signals in the 23- to 30-kHz range—frequencies in the first sonar harmonic—generally evoked phasic suppression of BF responses. This may result from neural inhibitory interactions within and below IC. In many neurons, we observed two or more forms of the spectral interactions described here. Thus IC neurons display temporally and spectrally complex responses to sound that result from multiple spectral interactions at different levels of the ascending auditory pathway.

scholarly journals Piglets vocally express the anticipation of pseudo-social contexts in their grunts

2020 ◽  
Vol 10 (1) ◽  
Author(s):  
A. S. Villain ◽  
A. Hazard ◽  
M. Danglot ◽  
C. Guérin ◽  
A. Boissy ◽  
...  
Keyword(s):  
Positive Emotions ◽  
Low Frequency ◽  
Social Contexts ◽  
Emotional States ◽  
Spectral Parameters ◽  
Emotional Context ◽  
Social Events ◽  
Temporal Features ◽  
Emotional Value ◽  
Vocal Expressions

Abstract Emotions not only arise in reaction to an event but also while anticipating it, making this context a means of accessing the emotional value of events. Before now, anticipatory studies have rarely considered whether vocalisations carry information about emotional states. We studied both the grunts of piglets and their spatial behaviour as they anticipated two (pseudo)social events known to elicit positive emotions of different intensity: arrival of familiar conspecifics and arrival of a familiar human. Piglets spatially anticipated both pseudo-social contexts, and the spectro temporal features of grunts differed according to the emotional context. Piglets produced low-frequency grunts at a higher rate when anticipating conspecifics compared to anticipating a human. Spectral noise increased when piglets expected conspecifics, whereas the duration and frequency range increased when expecting a human. When the arrival of conspecifics was delayed, the grunt duration increased, whereas when the arrival of the human was delayed, the spectral parameters were comparable to those during isolation. This shows that vocal expressions in piglets during anticipation are specific to the expected reward. Vocal expressions—both their temporal and spectral features- are thus a good way to explore the emotional state of piglets during the anticipation of challenging events.

Comparison of vestibular evoked myogenic potentials elicited by click and short duration tone burst stimuli

2010 ◽  
Vol 125 (4) ◽  
pp. 343-347 ◽  
Author(s):  
K Kumar ◽  
S Kumar Sinha ◽  
A Kumar Bharti ◽  
A Barman
Keyword(s):  
Short Duration ◽  
Clinical Assessment ◽  
Low Frequency ◽  
Tone Burst ◽  
Normal Hearing ◽  
Vestibular Evoked Myogenic Potentials ◽  
Vestibular Evoked Myogenic Potential ◽  
Acoustic Stimuli ◽  
Myogenic Potential ◽  
Electrical Impulses

AbstractIntroduction:Vestibular evoked myogenic potentials are short latency electrical impulses that are produced in response to higher level acoustic stimuli. They are used clinically to diagnose sacculocollic pathway dysfunction.Aim:This study aimed to compare the vestibular evoked myogenic potential responses elicited by click stimuli and short duration tone burst stimuli, in normal hearing individuals.Method:Seventeen subjects participated. In all subjects, we assessed vestibular evoked myogenic potentials elicited by click and short duration tone burst stimuli.Results and conclusion:The latency of the vestibular evoked myogenic potential responses (i.e. the p13 and n23 peaks) was longer for tone burst stimuli compared with click stimuli. The amplitude of the p13–n23 waveform was greater for tone burst stimuli than click stimuli. Thus, the click stimulus may be preferable for clinical assessment and identification of abnormalities as this stimulus has less variability, while a low frequency tone burst stimulus may be preferable when assessing the presence or absence of vestibular evoked myogenic potential responses.

scholarly journals Circuit-specific sonogenetic stimulation of the deep brain elicits distinct signaling and behaviors in freely moving mice

2021 ◽  
Author(s):  
Quanxiang Xian ◽  
Zhihai Qiu ◽  
Shashwati Kala ◽  
Kin Fung Wong ◽  
Suresh Murugappan ◽  
...  
Keyword(s):  
Low Frequency ◽  
Dorsal Striatum ◽  
Neural Pathways ◽  
Spatiotemporal Resolution ◽  
Trigger Activity ◽  
Freely Moving ◽  
Subcortical Regions ◽  
Ultrasonic Stimulation ◽  
Deep Brain ◽  
Stimulation Of

Sonogenetics uses heterologously-expressed proteins to sensitize neurons to ultrasound, enabling selective, non-invasive, and deep brain stimulation. However, its ability to modulate specific circuits or induce behavioral changes remains to be studied and characterized. Here, we demonstrate that sonogenetics enables efficient activation of well-defined neural circuits by transcranial low-intensity, low-frequency ultrasonic stimulation with high spatiotemporal resolution. Targeted neurons in subcortical regions were made to express a mechanosensitive ion channel (MscL-G22S). Ultrasound could trigger activity in MscL-expressing neurons in the dorsal striatum without increased activation in neighboring regions, and increase locomotion in freely-moving mice. Ultrasound stimulation of MscL-expressing neurons in the ventral tegmental area could activate the mesolimbic pathway to trigger dopamine release in the nucleus accumbens and modulate appetitive conditioning. In MscL-expressing cells, neuronal responses to ultrasound pulses were rapid, reversible and repeatable. Altogether, we show that sonogenetics can selectively manipulate targeted cells to activate defined neural pathways and affect behaviors.

SPET Monitoring of Perfusion Changes in Auditory Cortex following Mono- and Multi-Frequency Stimuli

1996 ◽  
Vol 35 (04) ◽  
pp. 112-115 ◽  
Author(s):  
Gaetano Paludetti ◽  
Walter di Nardo ◽  
Maria Calcagni ◽  
Daniela di Giuda ◽  
Giovanni Almadori ◽  
...  
Keyword(s):  
Auditory Cortex ◽  
High Intensity ◽  
Pure Tone ◽  
Low Frequency ◽  
Reliable Information ◽  
Research Support ◽  
Acoustic Stimuli ◽  
Cortical Areas ◽  
Contralateral Cortex ◽  
The Relationship

Summary Aim: In order to assess the relationship between auditory cortex perfusion and the frequency of acoustic stimuli, twenty normally-hearing subjects underwent cerebral SPET. Methods: In 10 patients a multi-frequency stimulus (250-4000 Hz at 40 dB SL) was delivered, while 10 subjects were stimulated with a 500 Hz pure tone at 40 dB SL. The prestimulation SPET was subtracted from poststimulation study and auditory cortex activation was expressed as percent increments. Results: Contralateral cortex was the most active area with multi-frequency and monofrequency stimuli as well. A clear demonstration of a tonotopic distribution of acoustic stimuli in the auditory cortex was achieved. In addition, the accessory role played by homolateral acoustic areas was confirmed. Conclusion: The results of the present research support the hypothesis that brain SPET may be useful to obtain semiquantitative reliable information on low frequency auditory level in profoundly deaf patients. This may be achieved comparing the extension of the cortical areas activated by high-intensity multifrequency stimuli.

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