Neuronal Encoding in a High-Level Auditory Area: From Sequential Order of Elements to Grammatical Structure

Introduction. The article is devoted to the study of the features of inflection skills of the preschoolers with a general speech disorders. The problem of studying the grammatical structure of speech plays a leading role in modern scientific and practical research, and the question of the mechanisms of the formation of grammatical patterns of language of children having general speech underdevelopment and the development of recommendations for speech therapy effects on this basis is especially relevant. Taking this factor into consideration, it is important to study the characteristics of inflection skills of preschoolers with a general speech disorders, as one of the categories of the grammatical structure. Accordingly, the purpose of the study was to investigate the characteristics of inflection skills of preschoolers with general speech underdevelopment. In accordance with the purpose, the course of the study is described, its results are analyzed, and conclusions are formulated. Accordingly, recommendations for speech therapy have been developed.Materials and methods. The study of the features of inflection skills of preschoolers with a general underdevelopment of speech was carried out in several stages. At the stage of analysis, synthesis, generalization and comparison of scientific literature data, the main theoretical and practical works of leading specialists were studied, dealing with the problem of formation and development of inflection skills in both normal and impaired speech development process. At the stage of the ascertaining experiment, preschoolers were offered a test aimed at determining the level of formation of inflection skills. At the final stage, empirical methods for processing empirical data (quantitative and qualitative analysis) were used.Results. As a result of the study, it was found that the inflection skills of preschool children with general speech disorders are mainly formed at a lower-than-average level, while their peers with normal speech development are formed at a high level. The hypothesis of the study, which suggested that the word-modification skills of preschoolers with General speech disorders, in contrast to preschoolers with normal speech development, are characterized by inconsistencies in gender, number, case of nouns and adjectives, errors in the use of forms of number and gender of verbs, was confirmed.Discussion and Conclusions. Taking into consideration the results of the study, we concluded that there is a need for speech therapy to compensate for the underdevelopment of inflection skills, as a result, logopedic recommendations were developed for developing inflection skills of preschool children with general speech disorders, which are part of a comprehensive speech therapy on the development of oral speech.

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Distinct timescales for the neuronal encoding of vocal signals in a high-order auditory area

10.1101/2021.06.28.450187 ◽

2021 ◽

Author(s):

Aurore Cazala ◽

Catherine Del Negro ◽

Nicolas Giret

Keyword(s):

Auditory Processing ◽

Vocal Communication ◽

High Order ◽

Functional Roles ◽

Global Context ◽

Vocal Signals ◽

Natural Sound ◽

Auditory Area ◽

Natural Variations ◽

Neuronal Encoding

The ability of the auditory system to selectively recognize natural sound categories with a tolerance to variations within categories is thought to be crucial for vocal communication. Subtle variations, however, may have functional roles. To date, how the coding of the balance between tolerance and sensitivity to variations in acoustic signals is performed at the neuronal level requires further studies. We investigated whether neurons of a high-order auditory area in a songbird species, the zebra finch, are sensitive to natural variations in vocal signals by recording responses to repeated exposure to similar and variant sound sequences. We took advantage of the intensive repetition of the male songs which subtly vary from rendition to rendition. In both anesthetized and awake birds, responses based on firing rate during sequence presentation did not show any clear sensitivity to these variations, unlike the temporal reliability of responses based on a 10 milliseconds resolution that depended on whether variant or similar sequences were broadcasted and the context of presentation. Results therefore suggest that auditory processing operates on distinct timescales, a short one to detect variations in individual's vocal signals, longer ones that allow tolerance in vocal signal structure and the encoding of the global context.

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What's That Sound? Auditory Area CLM Encodes Stimulus Surprise, Not Intensity or Intensity Changes

Journal of Neurophysiology ◽

10.1152/jn.01270.2007 ◽

2008 ◽

Vol 99 (6) ◽

pp. 2809-2820 ◽

Cited By ~ 44

Author(s):

Patrick Gill ◽

Sarah M. N. Woolley ◽

Thane Fremouw ◽

Frédéric E. Theunissen

Keyword(s):

Stimulus Intensity ◽

Linear Models ◽

Explanatory Power ◽

Linear Functions ◽

Neural Responses ◽

Auditory Neurons ◽

Linear Filters ◽

Auditory Area ◽

Intensity Changes ◽

High Level

High-level sensory neurons encoding natural stimuli are not well described by linear models operating on the time-varying stimulus intensity. Here we show that firing rates of neurons in a secondary sensory forebrain area can be better modeled by linear functions of how surprising the stimulus is. We modeled auditory neurons in the caudal lateral mesopallium (CLM) of adult male zebra finches under urethane anesthesia with linear filters convolved not with stimulus intensity, but with stimulus surprise. Surprise was quantified as the logarithm of the probability of the stimulus given the local recent stimulus history and expectations based on conspecific song. Using our surprise method, the predictions of neural responses to conspecific song improved by 67% relative to those obtained using stimulus intensity. Similar prediction improvements cannot be replicated by assuming CLM performs derivative detection. The explanatory power of surprise increased from the midbrain through the primary forebrain and to CLM. When the stimulus presented was a random synthetic ripple noise, CLM neurons (but not neurons in lower auditory areas) were best described as if they were expecting conspecific song, finding the inconsistencies between birdsong and noise surprising. In summary, spikes in CLM neurons indicate stimulus surprise more than they indicate stimulus intensity features. The concept of stimulus surprise may be useful for modeling neural responses in other higher-order sensory areas whose functions have been poorly understood.

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Distinct timescales for the neuronal encoding of vocal signals in a high-order auditory area

Scientific Reports ◽

10.1038/s41598-021-99135-w ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Aurore Cazala ◽

Catherine Del Negro ◽

Nicolas Giret

Keyword(s):

Auditory Processing ◽

Vocal Communication ◽

High Order ◽

Functional Roles ◽

Global Context ◽

Vocal Signals ◽

Natural Sound ◽

Auditory Area ◽

Natural Variations ◽

Neuronal Encoding

AbstractThe ability of the auditory system to selectively recognize natural sound categories while maintaining a certain degree of tolerance towards variations within these categories, which may have functional roles, is thought to be crucial for vocal communication. To date, it is still largely unknown how the balance between tolerance and sensitivity to variations in acoustic signals is coded at a neuronal level. Here, we investigate whether neurons in a high-order auditory area in zebra finches, a songbird species, are sensitive to natural variations in vocal signals by recording their responses to repeated exposures to identical and variant sound sequences. We used the songs of male birds which tend to be highly repetitive with only subtle variations between renditions. When playing these songs to both anesthetized and awake birds, we found that variations between songs did not affect the neuron firing rate but the temporal reliability of responses. This suggests that auditory processing operates on a range of distinct timescales, namely a short one to detect variations in vocal signals, and longer ones that allow the birds to tolerate variations in vocal signal structure and to encode the global context.

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Transcription factor/DNA interactions visualized by electron spectroscopic imaging

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100122654 ◽

1992 ◽

Vol 50 (1) ◽

pp. 450-451

Author(s):

David P. Bazett-Jones ◽

Mark L. Brown

Keyword(s):

Transcription Factor ◽

Dna Sequences ◽

Transcription Initiation ◽

Molecular Mechanisms ◽

Phosphorus Content ◽

Spectroscopic Imaging ◽

Electron Spectroscopic Imaging ◽

Dna Backbone ◽

Two Parameters ◽

High Level

A multisubunit RNA polymerase enzyme is ultimately responsible for transcription initiation and elongation of RNA, but recognition of the proper start site by the enzyme is regulated by general, temporal and gene-specific trans-factors interacting at promoter and enhancer DNA sequences. To understand the molecular mechanisms which precisely regulate the transcription initiation event, it is crucial to elucidate the structure of the transcription factor/DNA complexes involved. Electron spectroscopic imaging (ESI) provides the opportunity to visualize individual DNA molecules. Enhancement of DNA contrast with ESI is accomplished by imaging with electrons that have interacted with inner shell electrons of phosphorus in the DNA backbone. Phosphorus detection at this intermediately high level of resolution (≈lnm) permits selective imaging of the DNA, to determine whether the protein factors compact, bend or wrap the DNA. Simultaneously, mass analysis and phosphorus content can be measured quantitatively, using adjacent DNA or tobacco mosaic virus (TMV) as mass and phosphorus standards. These two parameters provide stoichiometric information relating the ratios of protein:DNA content.

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Advances in Stem Instrumentation for Biology

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100180562 ◽

1990 ◽

Vol 48 (1) ◽

pp. 362-363

Author(s):

J. S. Wall

Keyword(s):

Scanning Transmission Electron Microscope ◽

Carbon Films ◽

Specimen Preparation ◽

Material Deposition ◽

Active User ◽

Percent Improvement ◽

Scanning Transmission ◽

The Moment ◽

Film Substrate ◽

High Level

The forte of the Scanning transmission Electron Microscope (STEM) is high resolution imaging with high contrast on thin specimens, as demonstrated by visualization of single heavy atoms. of equal importance for biology is the efficient utilization of all available signals, permitting low dose imaging of unstained single molecules such as DNA.Our work at Brookhaven has concentrated on: 1) design and construction of instruments optimized for a narrow range of biological applications and 2) use of such instruments in a very active user/collaborator program. Therefore our program is highly interactive with a strong emphasis on producing results which are interpretable with a high level of confidence.The major challenge we face at the moment is specimen preparation. The resolution of the STEM is better than 2.5 A, but measurements of resolution vs. dose level off at a resolution of 20 A at a dose of 10 el/A2 on a well-behaved biological specimen such as TMV (tobacco mosaic virus). To track down this problem we are examining all aspects of specimen preparation: purification of biological material, deposition on the thin film substrate, washing, fast freezing and freeze drying. As we attempt to improve our equipment/technique, we use image analysis of TMV internal controls included in all STEM samples as a monitor sensitive enough to detect even a few percent improvement. For delicate specimens, carbon films can be very harsh-leading to disruption of the sample. Therefore we are developing conducting polymer films as alternative substrates, as described elsewhere in these Proceedings. For specimen preparation studies, we have identified (from our user/collaborator program ) a variety of “canary” specimens, each uniquely sensitive to one particular aspect of sample preparation, so we can attempt to separate the variables involved.

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A Questionnaire Survey of Current Rehabilitation Practices for Adults With Normal Hearing Sensitivity Who Experience Auditory Difficulties

American Journal of Audiology ◽

10.1044/2020_aja-20-00027 ◽

2020 ◽

Vol 29 (4) ◽

pp. 738-761

Author(s):

Tess K. Koerner ◽

Melissa A. Papesh ◽

Frederick J. Gallun

Keyword(s):

Hearing Aids ◽

Questionnaire Survey ◽

Patient Population ◽

Clinical Care ◽

Normal Hearing ◽

Auditory Training ◽

Training Methods ◽

Hearing Sensitivity ◽

Considerable Benefit ◽

High Level

Purpose A questionnaire survey was conducted to collect information from clinical audiologists about rehabilitation options for adult patients who report significant auditory difficulties despite having normal or near-normal hearing sensitivity. This work aimed to provide more information about what audiologists are currently doing in the clinic to manage auditory difficulties in this patient population and their views on the efficacy of recommended rehabilitation methods. Method A questionnaire survey containing multiple-choice and open-ended questions was developed and disseminated online. Invitations to participate were delivered via e-mail listservs and through business cards provided at annual audiology conferences. All responses were anonymous at the time of data collection. Results Responses were collected from 209 participants. The majority of participants reported seeing at least one normal-hearing patient per month who reported significant communication difficulties. However, few respondents indicated that their location had specific protocols for the treatment of these patients. Counseling was reported as the most frequent rehabilitation method, but results revealed that audiologists across various work settings are also successfully starting to fit patients with mild-gain hearing aids. Responses indicated that patient compliance with computer-based auditory training methods was regarded as low, with patients generally preferring device-based rehabilitation options. Conclusions Results from this questionnaire survey strongly suggest that audiologists frequently see normal-hearing patients who report auditory difficulties, but that few clinicians are equipped with established protocols for diagnosis and management. While many feel that mild-gain hearing aids provide considerable benefit for these patients, very little research has been conducted to date to support the use of hearing aids or other rehabilitation options for this unique patient population. This study reveals the critical need for additional research to establish evidence-based practice guidelines that will empower clinicians to provide a high level of clinical care and effective rehabilitation strategies to these patients.

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