scholarly journals Inhibitory Network Interactions Shape the Auditory Processing of Natural Communication Signals in the Songbird Auditory Forebrain

2008 ◽  
Vol 100 (1) ◽  
pp. 441-455 ◽  
Author(s):  
Raphael Pinaud ◽  
Thomas A. Terleph ◽  
Liisa A. Tremere ◽  
Mimi L. Phan ◽  
André A. Dagostin ◽  
...  

The role of GABA in the central processing of complex auditory signals is not fully understood. We have studied the involvement of GABAA-mediated inhibition in the processing of birdsong, a learned vocal communication signal requiring intact hearing for its development and maintenance. We focused on caudomedial nidopallium (NCM), an area analogous to parts of the mammalian auditory cortex with selective responses to birdsong. We present evidence that GABAA-mediated inhibition plays a pronounced role in NCM's auditory processing of birdsong. Using immunocytochemistry, we show that approximately half of NCM's neurons are GABAergic. Whole cell patch-clamp recordings in a slice preparation demonstrate that, at rest, spontaneously active GABAergic synapses inhibit excitatory inputs onto NCM neurons via GABAA receptors. Multi-electrode electrophysiological recordings in awake birds show that local blockade of GABAA-mediated inhibition in NCM markedly affects the temporal pattern of song-evoked responses in NCM without modifications in frequency tuning. Surprisingly, this blockade increases the phasic and largely suppresses the tonic response component, reflecting dynamic relationships of inhibitory networks that could include disinhibition. Thus processing of learned natural communication sounds in songbirds, and possibly other vocal learners, may depend on complex interactions of inhibitory networks.

Author(s):  
Anna Rasmus ◽  
Aleksandra Błachnio

Background: Language communication, which is one of the basic forms of building and maintaining interpersonal relationships, deteriorates in elder age. One of the probable causes is a decline in auditory functioning, including auditory central processing. The aim of the present study is to evaluate the profile of central auditory processing disorders in the elderly as well as the relationship between these disorders and the perception of emotional and linguistic prosody. Methods: The Right Hemisphere Language Battery (RHLB-PL), and the Brain-Boy Universal Professional (BUP) were used. Results: There are statistically significant relationships between emotional prosody and: spatial hearing (r(18) = 0.46, p = 0.04); the time of the reaction (r(18) = 0.49, p = 0.03); recognizing the frequency pattern (r(18) = 0.49, p = 0.03 (4); and recognizing the duration pattern (r(18) = 0.45, p = 0.05. There are statistically significant correlations between linguistic prosody and: pitch discrimination (r(18) = 0.5, p = 0.02); recognition of the frequency pattern (r(18) = 0.55, p = 0.01); recognition of the temporal pattern; and emotional prosody (r(18) = 0.58, p = 0.01). Conclusions: The analysis of the disturbed components of auditory central processing among the tested samples showed a reduction in the functions related to frequency differentiation, the recognition of the temporal pattern, the process of discriminating between important sounds, and the speed of reaction. De-automation of the basic functions of auditory central processing, which we observe in older age, lowers the perception of both emotional and linguistic prosody, thus reducing the quality of communication in older people.


2012 ◽  
Vol 107 (4) ◽  
pp. 1241-1246 ◽  
Author(s):  
Gary Marsat ◽  
Leonard Maler

To interact with the environment efficiently, the nervous system must generate expectations about redundant sensory signals and detect unexpected ones. Neural circuits can, for example, compare a prediction of the sensory signal that was generated by the nervous system with the incoming sensory input, to generate a response selective to novel stimuli. In the first-order electrosensory neurons of a gymnotiform electric fish, a negative image of low-frequency redundant communication signals is subtracted from the neural response via feedback, allowing unpredictable signals to be extracted. Here we show that the cancelling feedback not only suppresses the predictable signal but also actively enhances the response to the unpredictable communication signal. A transient mismatch between the predictive feedback and incoming sensory input causes both to be positive: the soma is suddenly depolarized by the unpredictable input, whereas the neuron's apical dendrites remain depolarized by the lagging cancelling feedback. The apical dendrites allow the backpropagation of somatic spikes. We show that backpropagation is enhanced when the dendrites are depolarized, causing the unpredictable excitatory input to evoke spike bursts. As a consequence, the feedback driven by a predictable low-frequency signal not only suppresses the response to a redundant stimulus but also induces a bursting response triggered by unpredictable communication signals.


Author(s):  
К.Г. Кебкал

На результатах численного моделирования продемонстрировано, что распределения вероятностей огибающей и фазы смеси гауссова шума и (слабого) гидроакустического сигнала связи, характеризуемого линейной разверткой несущей, могут иметь исчезающе малые отличия от аналогичных распределений, характерных для просто гауссова шума. Использование непрерывного расширения спектра сигнала связи может представлять интерес для задач скрытого обмена данными, в которых обнаружение сеанса связи устройствами перехвата должно быть затруднительным или невозможным. С применением численных моделей проанализированы возможности использования сигналов с непрерывным расширением спектра для скрытой цифровой гидроакустической связи посредством штатных приемоизлучающих гидроакустических систем, находящихся на вооружении действующих кораблей. Based on the results of the numerical modeling, the vanishingly small differences between the probability distributions of the envelope and phase of the sum of Gaussian noise and (weak) underwater acoustic signal with linear carrier sweep, and the same distributions for the Gaussian noise all alone are demonstrated. Utilization of the continuous spectrum spread of the communication signal may be applied to the task of covert data exchange, where detection of the communication session by the intercepting equipment must be complicated or impossible. Using numerical models, we analyzed the capabilities of implementation of the signals with continuous spectrum spread for covert digital underwater acoustic communications through the standard underwater acoustic transducers, which are in service on the operational ready vessels.


2021 ◽  
Author(s):  
Nasim Winchester Vahidi

The mechanisms underlying how single auditory neurons and neuron populations encode natural and acoustically complex vocal signals, such as human speech or bird songs, are not well understood. Classical models focus on individual neurons, whose spike rates vary systematically as a function of change in a small number of simple acoustic dimensions. However, neurons in the caudal medial nidopallium (NCM), an auditory forebrain region in songbirds that is analogous to the secondary auditory cortex in mammals, have composite receptive fields (CRFs) that comprise multiple acoustic features tied to both increases and decreases in firing rates. Here, we investigated the anatomical organization and temporal activation patterns of auditory CRFs in European starlings exposed to natural vocal communication signals (songs). We recorded extracellular electrophysiological responses to various bird songs at auditory NCM sites, including both single and multiple neurons, and we then applied a quadratic model to extract large sets of CRF features that were tied to excitatory and suppressive responses at each measurement site. We found that the superset of CRF features yielded spatially and temporally distributed, generalizable representations of a conspecific song. Individual sites responded to acoustically diverse features, as there was no discernable organization of features across anatomically ordered sites. The CRF features at each site yielded broad, temporally distributed responses that spanned the entire duration of many starling songs, which can last for 50 s or more. Based on these results, we estimated that a nearly complete representation of any conspecific song, regardless of length, can be obtained by evaluating populations as small as 100 neurons. We conclude that natural acoustic communication signals drive a distributed yet highly redundant representation across the songbird auditory forebrain, in which adjacent neurons contribute to the encoding of multiple diverse and time-varying spectro-temporal features.


2012 ◽  
Vol 263-266 ◽  
pp. 188-191
Author(s):  
Xiu Ying Sun ◽  
Peng Fei Xu

In this paper, a method for convolutive blind separation for communication sources is introduced. The method works in time-domain, and it is based on the recently very successful algorithm EFICA for Independent Component Analysis, which is an enhanced version of more famous FastICA. In addition, an automatic method of wavelet de-noising processing is proposed, using the 'mini-maxi' soft-threshold model, wavelet decomposition is performed at level 5 for the noisy separated communication signal, it can improve the performance of BSS system, and this is confirmed in the experiment for communication signals with same carrier frequencies and modulation.


2019 ◽  
Vol 94 (Suppl. 1-4) ◽  
pp. 51-60
Author(s):  
Julie E. Elie ◽  
Susanne Hoffmann ◽  
Jeffery L. Dunning ◽  
Melissa J. Coleman ◽  
Eric S. Fortune ◽  
...  

Acoustic communication signals are typically generated to influence the behavior of conspecific receivers. In songbirds, for instance, such cues are routinely used by males to influence the behavior of females and rival males. There is remarkable diversity in vocalizations across songbird species, and the mechanisms of vocal production have been studied extensively, yet there has been comparatively little emphasis on how the receiver perceives those signals and uses that information to direct subsequent actions. Here, we emphasize the receiver as an active participant in the communication process. The roles of sender and receiver can alternate between individuals, resulting in an emergent feedback loop that governs the behavior of both. We describe three lines of research that are beginning to reveal the neural mechanisms that underlie the reciprocal exchange of information in communication. These lines of research focus on the perception of the repertoire of songbird vocalizations, evaluation of vocalizations in mate choice, and the coordination of duet singing.


2006 ◽  
Vol 96 (5) ◽  
pp. 2177-2188 ◽  
Author(s):  
Laura M. Hurley

The neuromodulator serotonin has a complex set of effects on the auditory responses of neurons within the inferior colliculus (IC), a midbrain auditory nucleus that integrates a wide range of inputs from auditory and nonauditory sources. To determine whether activation of different types of serotonin receptors is a source of the variability in serotonergic effects, four selective agonists of serotonin receptors in the serotonin (5-HT) 1 and 5-HT2 families were iontophoretically applied to IC neurons, which were monitored for changes in their responses to auditory stimuli. Different agonists had different effects on neural responses. The 5-HT1A agonist had mixed facilitatory and depressive effects, whereas 5-HT1B and 5-HT2C agonists were both largely facilitatory. Different agonists changed threshold and frequency tuning in ways that reflected their effects on spike count. When pairs of agonists were applied sequentially to the same neurons, selective agonists sometimes affected neurons in ways that were similar to serotonin, but not to other selective agonists tested. Different agonists also differentially affected groups of neurons classified by the shapes of their frequency-tuning curves, with serotonin and the 5-HT1 receptors affecting proportionally more non-V-type neurons relative to the other agonists tested. In all, evidence suggests that the diversity of serotonin receptor subtypes in the IC is likely to account for at least some of the variability of the effects of serotonin and that receptor subtypes fulfill specialized roles in auditory processing.


2008 ◽  
Vol 17 (05) ◽  
pp. 957-971
Author(s):  
ATAOLLAH EBRAHIMZADEH ◽  
ABOLFAZL RANJBAR ◽  
MEHRDAD ARDEBLILPOUR

Classification of the communication signals has seen under increasing demands. In this paper, we present a new technique that identifies a variety of digital communication signal types. This technique utilizes a radial basis function neural network (RBFN) as the classifier. Swarm intelligence, as an evolutionary algorithm, is used to construct RBFN. A combination of the higher-order moments and the higher-order cumulants up to eight are selected as the features of the considered digital signal types. In conjunction with RBFN, we have used k-fold cross-validation to improve the generalization potentiality. Simulation results show that the proposed technique has high performance for classification of different communication signals even at very low signal-to-noise ratios.


2015 ◽  
Vol 76 (1) ◽  
pp. 47-63 ◽  
Author(s):  
Laura E. Matheson ◽  
Herie Sun ◽  
Jon T. Sakata

2019 ◽  
Author(s):  
Kei Hori ◽  
Kunihiko Yamashiro ◽  
Taku Nagai ◽  
Wei Shan ◽  
Saki F. Egusa ◽  
...  

AbstractImpairments in synapse development are thought to cause numerous psychiatric disorders. Autism susceptibility candidate 2 (AUTS2) gene has been associated with various psychiatric disorders, such as autism and intellectual disabilities. Although roles for AUTS2 in neuronal migration and neuritogenesis have been reported, its involvement in synapse regulation remains unclear. In this study, we found that excitatory synapses were specifically increased in the Auts2-deficient primary cultured neurons as well as Auts2 mutant forebrains. Electrophysiological recordings and immunostaining showed increases in excitatory synaptic inputs as well as c-fos expression in Auts2 mutant brains, suggesting that an altered balance of excitatory and inhibitory inputs enhances brain excitability. Auts2 mutant mice exhibited autistic-like behaviors including impairments in social interaction and altered vocal communication. Together, these findings suggest that AUTS2 regulates excitatory synapse number to coordinate E/I balance in the brain, whose impairment may underlie the pathology of psychiatric disorders in individuals with AUTS2 mutations.


Sign in / Sign up

Export Citation Format

Share Document