Steady-state response by time-reversal FD-TD method with Lanczos algorithm

Two studies were aimed at developing the auditory steady-state response (ASSR) for universal newborn hearing screening. First, neonates who had passed auditory brainstem response, transient evoked otoacoustic emission, and distortion-product otoacoustic emission tests were also tested with ASSRs using modulated tones that varied in frequency and level. Pass rates were highest (> 90%) for amplitude-modulated tones presented at levels ≥ 69 dB SPL. The effect of modulation frequency on ASSR for 500- and 2000-Hz tones was evaluated in full-term and premature infants in the second study. Full-term infants had higher pass rates for 2000-Hz tones amplitude modulated at 74 to 106 Hz compared with pass rates for a 500-Hz tone modulated at 58 to 90 Hz. Premature infants had lower pass rates than full-term infants for both carrier frequencies. Systematic investigation of ASSR threshold and the effect of modulation frequency in neonates is needed to adapt the technique for screening.

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The Auditory Steady-State Response

Journal of the American Academy of Audiology ◽

10.1055/s-0040-1715960 ◽

2002 ◽

Vol 13 (04) ◽

pp. i-i

Author(s):

James Jerger

Keyword(s):

Steady State ◽

Steady State Response ◽

State Response ◽

Auditory Steady State Response

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Steady State Response of Linear Time Invariant Systems Modeledby Multibond Graphs

Applied Sciences ◽

10.3390/app11041717 ◽

2021 ◽

Vol 11 (4) ◽

pp. 1717

Author(s):

Gilberto Gonzalez Avalos ◽

Noe Barrera Gallegos ◽

Gerardo Ayala-Jaimes ◽

Aaron Padilla Garcia

Keyword(s):

Steady State ◽

Linear Time ◽

Direct Determination ◽

The State ◽

Steady State Response ◽

State Variables ◽

Linear Time Invariant ◽

State Response ◽

Time Invariant

The direct determination of the steady state response for linear time invariant (LTI) systems modeled by multibond graphs is presented. Firstly, a multiport junction structure of a multibond graph in an integral causality assignment (MBGI) to get the state space of the system is introduced. By assigning a derivative causality to the multiport storage elements, the multibond graph in a derivative causality (MBGD) is proposed. Based on this MBGD, a theorem to obtain the steady state response is presented. Two case studies to get the steady state of the state variables are applied. Both cases are modeled by multibond graphs, and the symbolic determination of the steady state is obtained. The simulation results using the 20-SIM software are numerically verified.

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Decreased Gamma Auditory Steady-State Response Is Associated With Impaired Real-World Functioning in Unmedicated Patients at Clinical High Risk for Psychosis

Clinical EEG and Neuroscience ◽

10.1177/1550059420982706 ◽

2020 ◽

pp. 155005942098270

Author(s):

Sarah Ahmed ◽

Jennifer R. Lepock ◽

Romina Mizrahi ◽

R. Michael Bagby ◽

Cory J. Gerritsen ◽

...

Keyword(s):

Steady State ◽

High Risk ◽

Functional Impairment ◽

Real World ◽

Steady State Response ◽

Clinical High Risk ◽

State Response ◽

Auditory Steady State Response ◽

Gamma Synchrony ◽

40 Hz

Aim Deficits in synchronous, gamma-frequency neural oscillations may contribute to schizophrenia patients’ real-world functional impairment and can be measured electroencephalographically using the auditory steady-state response (ASSR). Gamma ASSR deficits have been reported in schizophrenia patients and individuals at clinical high risk (CHR) for developing psychosis. We hypothesized that, in CHR patients, gamma ASSR would correlate with real-world functioning, consistent with a role for gamma synchrony deficits in functional impairment. Methods A total of 35 CHR patients rated on Global Functioning: Social and Role scales had EEG recorded while listening to 1-ms, 93-dB clicks presented at 40 Hz in 500-ms trains, in response to which 40-Hz evoked power and intertrial phase-locking factor (PLF) were measured. Results In CHR patients, lower 40-Hz PLF correlated with lower social functioning. Conclusions Gamma synchrony deficits may be a biomarker of real-world impairment at early stages of the schizophrenia disease trajectory.

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