scholarly journals Orthogonal neural codes for speech in the infant brain

2021 ◽  
Vol 118 (31) ◽  
pp. e2020410118
Author(s):  
Giulia Gennari ◽  
Sébastien Marti ◽  
Marie Palu ◽  
Ana Fló ◽  
Ghislaine Dehaene-Lambertz

Creating invariant representations from an everchanging speech signal is a major challenge for the human brain. Such an ability is particularly crucial for preverbal infants who must discover the phonological, lexical, and syntactic regularities of an extremely inconsistent signal in order to acquire language. Within the visual domain, an efficient neural solution to overcome variability consists in factorizing the input into a reduced set of orthogonal components. Here, we asked whether a similar decomposition strategy is used in early speech perception. Using a 256-channel electroencephalographic system, we recorded the neural responses of 3-mo-old infants to 120 natural consonant–vowel syllables with varying acoustic and phonetic profiles. Using multivariate pattern analyses, we show that syllables are factorized into distinct and orthogonal neural codes for consonants and vowels. Concerning consonants, we further demonstrate the existence of two stages of processing. A first phase is characterized by orthogonal and context-invariant neural codes for the dimensions of manner and place of articulation. Within the second stage, manner and place codes are integrated to recover the identity of the phoneme. We conclude that, despite the paucity of articulatory motor plans and speech production skills, pre-babbling infants are already equipped with a structured combinatorial code for speech analysis, which might account for the rapid pace of language acquisition during the first year.

2021 ◽  
Author(s):  
Giulia Gennari ◽  
Sebastien Marti ◽  
Marie Palu ◽  
Ana Flo ◽  
Ghislaine Dehaene-Lambertz

Creating invariant representations from an ever-changing speech signal is a major challenge for the human brain. Such an ability is particularly crucial for preverbal infants who must discover the phonological, lexical and syntactic regularities of an extremely inconsistent signal in order to acquire language. Within visual perception, an efficient neural solution to overcome signal variability consists in factorizing the input into orthogonal and relevant low-dimensional components. In this study we asked whether a similar neural strategy grounded on phonetic features is recruited in speech perception. Using a 256-channel electroencephalographic system, we recorded the neural responses of 3-month-old infants to 120 natural consonant-vowel syllables with varying acoustic and phonetic profiles. To characterize the specificity and granularity of the elicited representations, we employed a hierarchical generalization approach based on multivariate pattern analyses. We identified two stages of processing. At first, the features of manner and place of articulation were decodable as stable and independent dimensions of neural responsivity. Subsequently, phonetic features were integrated into phoneme-identity (i.e. consonant) neural codes. The latter remained distinct from the representation of the vowel, accounting for the different weights attributed to consonants and vowels in lexical and syntactic computations. This study reveals that, despite the paucity of articulatory motor plans and productive skills, the preverbal brain is already equipped with a structured phonetic space which provides a combinatorial code for speech analysis. The early availability of a stable and orthogonal neural code for phonetic features might account for the rapid pace of language acquisition during the first year.


2020 ◽  
Author(s):  
Hyesung Grace Hwang ◽  
Ranjan Debnath ◽  
Marlene Meyer ◽  
Virginia C. Salo ◽  
Nathan Fox ◽  
...  

Early in life, greater exposure to diverse people can change the tendency to prefer one’s own social group. For instance, infants from racially diverse environments show less preference for their own-race (ingroup) over other-race (outgroup) faces than infants from racially homogeneous environments. Yet how social environment changes ingroup versus outgroup demarcation in infancy is unclear. A commonly held assumption is that early emerging ingroup preference is based on an affective process: feeling more comfortable with familiar ingroup than unfamiliar outgroup members. However, other processes may also underlie ingroup preference: Infants may attend more to ingroup than outgroup members and/or mirror the actions of ingroup over outgroup individuals. By aggregating 7- to 12-month-old infants’ electroencephalography (EEG) activity across three studies, we disambiguate these different processes in the EEG oscillations of preverbal infants according to social environment. White infants from more racially diverse neighborhoods exhibited greater frontal theta oscillation (an index of top-down attention) and more mu rhythm desynchronization (an index of motor system activation and potentially neural mirroring) to racial outgroup individuals than White infants from less racially diverse neighborhoods. Neighborhood racial demographics did not relate to White infants’ frontal alpha asymmetry (a measure of approach-withdrawal motivation) toward racial outgroup individuals. Racial minority infants showed no effects of neighborhood racial demographics in their neural responses to racial outgroup individuals. These results indicate that neural mechanisms that may underlie social bias and prejudices are related to neighborhood racial demographics in the first year of life.


1992 ◽  
Vol 25 (4-5) ◽  
pp. 161-168 ◽  
Author(s):  
J. Einfeldt

A process, called Bio-Denipho, for combined biological phosphorus and nitrogen removal in a combination of an anaerobic tank and two oxidation ditches is described. In this process the anaerobic tank consisting of three sections working in series is followed by two oxidation ditches. These too are working in series, but with both inlet to and outlet from the tanks changing in a cycle. The Bio-Denipho process is described specifically for the process itself and as a case study for the implementation of the process on a 265,000 pe wastewater treatment plant for the city of Aalborg in Denmark. The plant was designed and erected in two stages and the last stage was inaugurated October 31,1989. Lay-out and functions for the plant is described and design loads, plan lay-out and tank volumes are given in this paper together with performance data for the first year in operation.


2017 ◽  
Vol 372 (1714) ◽  
pp. 20160105 ◽  
Author(s):  
Rosy Southwell ◽  
Anna Baumann ◽  
Cécile Gal ◽  
Nicolas Barascud ◽  
Karl Friston ◽  
...  

In this series of behavioural and electroencephalography (EEG) experiments, we investigate the extent to which repeating patterns of sounds capture attention. Work in the visual domain has revealed attentional capture by statistically predictable stimuli, consistent with predictive coding accounts which suggest that attention is drawn to sensory regularities. Here, stimuli comprised rapid sequences of tone pips, arranged in regular (REG) or random (RAND) patterns. EEG data demonstrate that the brain rapidly recognizes predictable patterns manifested as a rapid increase in responses to REG relative to RAND sequences. This increase is reminiscent of the increase in gain on neural responses to attended stimuli often seen in the neuroimaging literature, and thus consistent with the hypothesis that predictable sequences draw attention. To study potential attentional capture by auditory regularities, we used REG and RAND sequences in two different behavioural tasks designed to reveal effects of attentional capture by regularity. Overall, the pattern of results suggests that regularity does not capture attention. This article is part of the themed issue ‘Auditory and visual scene analysis’.


Author(s):  
А. М. Kholod

In the article an author formulates an aim: to describe and classify of communication technologies of the social engineering in the newspapers of Reichscommissariat "Ukraine" (RCU) in a period from September, 1, 1941 to July, 17, 1942. On results research: 1) it is set that more active than all in the newspapers of (RCU) on the first year his existence technologies of the first stage of the social engineering (namely are authentications) were used; 2) actively enough the authors of journalistic materials called to of communication technologies that declared "diffuse" character of confluence of two stages of the social engineering, namely are authentications and designs; 3) the no active enough (only in 9%) journalists of fascist newspapers of (RCU) called to of communication technologies of the stage of design of reality. Conclusions: the authors of journalistic materials did not aim to design future reality of "new order" of "Greatgermanium", and also did not have sufficient journalistic preparation and experience for realization Goebels and Hitler intentions.


Author(s):  
Olena H. Vasylchenko

The relevance of the research is determined by the need to find new methods of teaching a foreign language in the context of the transition to an online learning environment, which will contribute to ensuring an appropriate level of development of future specialists' communicative foreign competence. The purpose of the study is to determine the features of the development of students' phonetic competence in online German classes on the example of the pedagogical activity of teachers of the I.I. Mechnikov Odessa National University. The study of the selected problems was carried out in two stages based on logical and system approaches using general scientific methods, including the method of analysis, synthesis, comparison, concretisation, systematisation, and the method of analogies. It was identified that the modern educational space is characterised by the digitalisation of the educational process, as a result of which approaches to teaching a foreign language are changing. The paper considers foreign practices of using multimedia technologies in foreign language classes to form students' auditory and pronunciation skills in online learning. The necessity of changing the conventional methods of teaching an introductory phonetic course in a foreign language according to the requirements of distance learning was substantiated. It was established that the key factor in the development of auditory and pronunciation skills in online German classes is the use of video and audio materials (video conferences and messengers), animated images of articulation of sounds, as well as a system of exercises for the practical application of the theoretical knowledge obtained. On the example of teaching an introductory phonetic course in German for first-year students of the Department of International Relations of the I.I. Mechnikov Odessa National University, the basic principles of using mobile applications in the process of distance learning, including Padlet, LearningApps, Voki, PicVoice, and ChatterPix are described. The prospects for further research lie in the practice of using the online environment of an introductory German phonetic course among students of related specialisations


2018 ◽  
Author(s):  
Samuel A. Nastase ◽  
Ben Davis ◽  
Uri Hasson

AbstractCurrent neurobiological models assign a central role to predictive processes calibrated to environmental statistics. Neuroimaging studies examining the encoding of stimulus uncertainty have relied almost exclusively on manipulations in which stimuli were presented in a single sensory modality, and further assumed that neural responses vary monotonically with uncertainty. This has left a gap in theoretical development with respect to two core issues: i) are there cross-modal brain systems that encode input uncertainty in way that generalizes across sensory modalities, and ii) are there brain systems that track input uncertainty in a non-monotonic fashion? We used multivariate pattern analysis to address these two issues using auditory, visual and audiovisual inputs. We found signatures of cross-modal encoding in frontoparietal, orbitofrontal, and association cortices using a searchlight cross-classification analysis where classifiers trained to discriminate levels of uncertainty in one modality were tested in another modality. Additionally, we found widespread systems encoding uncertainty non-monotonically using classifiers trained to discriminate intermediate levels of uncertainty from both the highest and lowest uncertainty levels. These findings comprise the first comprehensive report of cross-modal and non-monotonic neural sensitivity to statistical regularities in the environment, and suggest that conventional paradigms testing for monotonic responses to uncertainty in a single sensory modality may have limited generalizability.


2019 ◽  
Author(s):  
Raviv Pryluk ◽  
Yosef Shohat ◽  
Anna Morozov ◽  
Dafna Friedman ◽  
Aryeh H. Taub ◽  
...  

AbstractThe eye-gaze of others is a prominent social cue in primates and crucial for communication1-7, and atypical processing occurs in several conditions as autism-spectrum-disorder (ASD)1,9-14. The neural mechanisms that underlie eye-gaze remain vague, and it is still debated if these computations developed in dedicated neural circuits or shared with non-social elements. In many species, eye-gaze signals a threat and elicits anxiety, yet can also serve as a predictor for the outcome of the encounter: negative or positive2,4,8. Here, we hypothesized and find that neural codes overlap between eye-gaze and valence. Monkeys participated in a modified version of the human-intruder-test8,15 that includes direct and averted eye-gaze and interleaved with blocks of aversive and appetitive conditioning16,17. We find that single-neurons in the amygdala encode gaze18, whereas neurons in the anterior-cingulate-cortex encode the social context19,20 but not gaze. We identify a shared amygdala circuitry where neural responses to averted and direct gaze parallel the responses to appetitive and aversive value, correspondingly. Importantly, we distinguish two shared coding mechanisms: a shared-intensity scheme that is used for gaze and the unconditioned-stimulus, and a shared-activity scheme that is used for gaze and the conditioned-stimulus. The shared-intensity points to overlap in circuitry, whereas the shared-activity requires also correlated activity. Our results demonstrate that eye-gaze is coded as a signal of valence, yet also as the expected value of the interaction. The findings may suggest new insights into the mechanisms that underlie the malfunction of eye-gaze in ASD and the comorbidity with impaired social skills and anxiety.


2018 ◽  
Vol 5 (1) ◽  
pp. 20 ◽  
Author(s):  
Hasti Suprihatin

The existing soft drink factory can produce liquid organic waste with a COD content starts from 6,000 mg/l to 15,000 mg/l with a discharge by 10 m3/day to 100 m3/day. The objective of the research is to obtain organic waste processing equipment that produces processing that meets the threshold value. The research outcomes are as a reference for the industry that requires a representative organic waste treatment unit.The research is divided into two stages in two years. The first year of the research is semi-aerobic and anaerobic process, then for second year is aerobic process research, semi-aerobic process, anaerobic process and aerobic process. The 12 hours HRT process at the first run resulted in a COD concentration of 12,000 mg/l to 8,765 mg/l directly entering an anaerobic I and out 4,640 mg/l and entering anaerobic II reactor and exiting with COD 1,380 mg/l. Decrease percentage of total COD (12,000 – 1,380) x 100 /12,000 = 88.5%. The 18 hours HRT process at the first run resulted in a COD concentration by 12,000 mg/l to 8,665 mg/l entering the anaerobic reactor I and out 4,125 mg/l and entering the anaerobic II and out with COD 965 mg/l. Decrease in total COD (12,000 - 965) x 100 / 12,000 = 91.95%.From the experimental stage of semi-aerobic step-screening-anaerobic treatment of two-stage liquid liquor soft drink obtained COD concentration of 12,000 mg/l can be reduced concentration to the threshold specified with removal of 88.5% - 91.95%.


2021 ◽  
Author(s):  
Jonathan Schaffner ◽  
Philippe Tobler ◽  
Todd Hare ◽  
Rafael Polania

It has generally been presumed that sensory information encoded by a nervous system should be as accurate as its biological limitations allow. However, perhaps counter intuitively, accurate representations of sensory signals do not necessarily maximize the organism's chances of survival. To test this hypothesis, we developed a unified normative framework for fitness-maximizing encoding by combining theoretical insights from neuroscience, computer science, and economics. Initially, we applied predictions of this model to neural responses from large monopolar cells (LMCs) in the blowfly retina. We found that neural codes that maximize reward expectation---and not accurate sensory representations---account for retinal LMC activity. We also conducted experiments in humans and find that early sensory areas flexibly adopt neural codes that promote fitness maximization in a retinotopically-specific manner, which impacted decision behavior. Thus, our results provide evidence that fitness-maximizing rules imposed by the environment are applied at the earliest stages of sensory processing.


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