scholarly journals Visual cortex entrains to sign language

2017 ◽  
Vol 114 (24) ◽  
pp. 6352-6357 ◽  
Author(s):  
Geoffrey Brookshire ◽  
Jenny Lu ◽  
Howard C. Nusbaum ◽  
Susan Goldin-Meadow ◽  
Daniel Casasanto
Keyword(s):  
Auditory Cortex ◽  
American Sign Language ◽  
Sign Language ◽  
Visual Information ◽  
Low Frequency ◽  
General Purpose ◽  
Visual Change ◽  
Neural Processes ◽  
Speech Envelope ◽  
Cortical Entrainment

Despite immense variability across languages, people can learn to understand any human language, spoken or signed. What neural mechanisms allow people to comprehend language across sensory modalities? When people listen to speech, electrophysiological oscillations in auditory cortex entrain to slow (<8 Hz) fluctuations in the acoustic envelope. Entrainment to the speech envelope may reflect mechanisms specialized for auditory perception. Alternatively, flexible entrainment may be a general-purpose cortical mechanism that optimizes sensitivity to rhythmic information regardless of modality. Here, we test these proposals by examining cortical coherence to visual information in sign language. First, we develop a metric to quantify visual change over time. We find quasiperiodic fluctuations in sign language, characterized by lower frequencies than fluctuations in speech. Next, we test for entrainment of neural oscillations to visual change in sign language, using electroencephalography (EEG) in fluent speakers of American Sign Language (ASL) as they watch videos in ASL. We find significant cortical entrainment to visual oscillations in sign language <5 Hz, peaking at ∼1 Hz. Coherence to sign is strongest over occipital and parietal cortex, in contrast to speech, where coherence is strongest over the auditory cortex. Nonsigners also show coherence to sign language, but entrainment at frontal sites is reduced relative to fluent signers. These results demonstrate that flexible cortical entrainment to language does not depend on neural processes that are specific to auditory speech perception. Low-frequency oscillatory entrainment may reflect a general cortical mechanism that maximizes sensitivity to informational peaks in time-varying signals.

scholarly journals Transcranial alternating current stimulation with speech envelopes modulates speech comprehension

2017 ◽  
Author(s):  
Anna Wilsch ◽  
Toralf Neuling ◽  
Jonas Obleser ◽  
Christoph S. Herrmann
Keyword(s):  
Auditory Cortex ◽  
Speech Signal ◽  
Speech Intelligibility ◽  
Sentence Comprehension ◽  
Average Frequency ◽  
Speech Comprehension ◽  
Time Lags ◽  
Transcranial Alternating Current Stimulation ◽  
Speech Envelope ◽  
Cortical Entrainment

AbstractCortical entrainment of the auditory cortex to the broadband temporal envelope of a speech signal is crucial for speech comprehension. Entrainment results in phases of high and low neural excitability, which structure and decode the incoming speech signal. Entrainment to speech is strongest in the theta frequency range (4–8 Hz), the average frequency of the speech envelope. If a speech signal is degraded, entrainment to the speech envelope is weaker and speech intelligibility declines. Besides perceptually evoked cortical entrainment, transcranial alternating current stimulation (tACS) entrains neural oscillations by applying an electric signal to the brain. Accordingly, tACS-induced entrainment in auditory cortex has been shown to improve auditory perception. The aim of the current study was to modulate speech intelligibility externally by means of tACS such that the electric current corresponds to the envelope of the presented speech stream (i.e., envelope-tACS). Participants performed the Oldenburg sentence test with sentences presented in noise in combination with envelope-tACS. Critically, tACS was induced at time lags of 0 to 250 ms in 50-ms steps relative to sentence onset (auditory stimuli were simultaneous to or preceded tACS). We performed single-subject sinusoidal, linear, and quadratic fits to the sentence comprehension performance across the time lags. We could show that the sinusoidal fit described the modulation of sentence comprehension best. Importantly, the average frequency of the sinusoidal fit was 5.12 Hz, corresponding to the peaks of the amplitude spectrum of the stimulated envelopes. This finding was supported by a significant 5-Hz peak in the average power spectrum of individual performance time series. Altogether, envelope tACS modulates intelligibility of speech in noise, presumably by enhancing and disrupting (time lag with in-or out-of-phase stimulation, respectively) cortical entrainment to the speech envelope in auditory cortex.

Spatial and temporal dynamics of lexico-semantic processing in American Sign Language

2011 ◽  
Author(s):  
M. Leonard ◽  
N. Ferjan Ramirez ◽  
C. Torres ◽  
M. Hatrak ◽  
R. Mayberry ◽  
...  
Keyword(s):  
American Sign Language ◽  
Sign Language ◽  
Semantic Processing ◽  
Temporal Dynamics ◽  
American Sign ◽  
Spatial And Temporal Dynamics

Patient Health Questionnaire-9--American Sign Language Version

2018 ◽  
Author(s):  
Leslie Pertz ◽  
Missy Plegue ◽  
Kathleen Diehl ◽  
Philip Zazove ◽  
Michael McKee
Keyword(s):  
American Sign Language ◽  
Sign Language ◽  
Patient Health Questionnaire ◽  
American Sign ◽  
Health Questionnaire ◽  
Language Version ◽  
Patient Health

scholarly journals Systematic Literature Review: American Sign Language Translator

2021 ◽  
Vol 179 ◽  
pp. 541-549
Author(s):  
Andra Ardiansyah ◽  
Brandon Hitoyoshi ◽  
Mario Halim ◽  
Novita Hanafiah ◽  
Aswin Wibisurya
Keyword(s):  
Literature Review ◽  
American Sign Language ◽  
Sign Language ◽  
Systematic Literature Review ◽  
American Sign

Crosslinguistic similarity and variation in the simultaneous morphology of sign languages

2020 ◽  
Vol 37 (4) ◽  
pp. 571-608
Author(s):  
Diane Brentari ◽  
Laura Horton ◽  
Susan Goldin-Meadow
Keyword(s):  
American Sign Language ◽  
Sign Language ◽  
Optimality Theory ◽  
Sign Languages ◽  
British Sign Language ◽  
Verb Phrases ◽  
Classifier Predicates ◽  
Crosslinguistic Variation ◽  
Hong Kong Sign Language ◽  
British Sign

Abstract Two differences between signed and spoken languages that have been widely discussed in the literature are: the degree to which morphology is expressed simultaneously (rather than sequentially), and the degree to which iconicity is used, particularly in predicates of motion and location, often referred to as classifier predicates. In this paper we analyze a set of properties marking agency and number in four sign languages for their crosslinguistic similarities and differences regarding simultaneity and iconicity. Data from American Sign Language (ASL), Italian Sign Language (LIS), British Sign Language (BSL), and Hong Kong Sign Language (HKSL) are analyzed. We find that iconic, cognitive, phonological, and morphological factors contribute to the distribution of these properties. We conduct two analyses—one of verbs and one of verb phrases. The analysis of classifier verbs shows that, as expected, all four languages exhibit many common formal and iconic properties in the expression of agency and number. The analysis of classifier verb phrases (VPs)—particularly, multiple-verb predicates—reveals (a) that it is grammatical in all four languages to express agency and number within a single verb, but also (b) that there is crosslinguistic variation in expressing agency and number across the four languages. We argue that this variation is motivated by how each language prioritizes, or ranks, several constraints. The rankings can be captured in Optimality Theory. Some constraints in this account, such as a constraint to be redundant, are found in all information systems and might be considered non-linguistic; however, the variation in constraint ranking in verb phrases reveals the grammatical and arbitrary nature of linguistic systems.

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