Event-Related Potential Measures of the Passive Processing of Rapidly and Slowly Presented Auditory Stimuli in MCI

Much research effort is currently devoted to the development of a simple, low-cost method to determine early signs of Alzheimer’s disease (AD) pathology. The present study employs a simple paradigm in which event-related potentials (ERPs) were recorded to a single auditory stimulus that was presented rapidly or very slowly while the participant was engaged in a visual task. A multi-channel EEG was recorded in 20 healthy older adults and 20 people with mild cognitive impairment (MCI). In two different conditions, a single 80 dB sound pressure level (SPL) auditory stimulus was presented every 1.5 s (fast condition) or every 12.0 s (slow condition). Participants were instructed to watch a silent video and ignore the auditory stimuli. Auditory processing thus occurred passively. When the auditory stimuli were presented rapidly (every 1.5 s), N1 and P2 amplitudes did not differ between the two groups. When the stimuli were presented very slowly, the amplitude of N1 and P2 increased in both groups and their latencies were prolonged. The amplitude of N1 did not significantly differ between the two groups. However, the subsequent positivity was reduced in people with MCI compared to healthy older adults. This late positivity in the slow condition may reflect a delayed P2 or a summation of a composite P2 + P3a. In people with MCI, the priority of processing may not be switched from the visual task to the potentially much more relevant auditory input. ERPs offer promise as a means to identify the pathology underlying cognitive impairment associated with MCI.

Speaking Clearly for Older Adults With Normal Hearing: The Role of Speaking Rate

Purpose Talkers typically use a slow speaking rate when producing clear speech, a speaking style that has been widely shown to improve intelligibility over conversational speech in difficult communication environments. With training, however, talkers can learn to produce a form of clear speech at normal speaking rates that provides young listeners with normal hearing much of the same intelligibility benefit. The purpose of this study was to determine if older listeners with normal hearing can also obtain an intelligibility benefit from clear speech at normal rates. Method Eight older listeners (55–68 years of age) with normal hearing were presented with nonsense sentences from 4 talkers in a background of speech-shaped noise (signal-to-noise ratio = 0 dB). Intelligibility (percent correct key words) was evaluated for conversational and clear speech produced at 2 speaking rates (normal and slow), for a total of 4 conditions: conv/normal, conv/slow, clear/normal, and clear/slow. Results As expected, the clear/slow speaking condition provided a large and robust intelligibility advantage (23 points) over conv/normal speech. The conv/slow condition provided almost as much benefit on average (21 points) but was highly variable across talkers. Notably, the clear/normal speaking condition provided the same size intelligibility advantage (14 points), previously reported for young listeners with normal hearing ( Krause & Braida, 2002 ), thus extending the benefit of clear speech at normal speaking rates to older normal-hearing listeners. Conclusions Applications based on clear/normal speech (e.g., signal processing approaches for hearing aids) have the potential to provide comparable intelligibility improvements to older and younger listeners alike.

Nonadiabaticity in Quantum Pumping Phenomena under Relaxation

The ability to control quanta shown by quantum pumping has been intensively studied, aiming to further develop nano fabrication. In accordance with the fast progress of the experimental techniques, the focus on quantum pumping extends to include the quicker transport. For this purpose, it is necessary to remove the “adiabatic” or “slow” condition, which has been the central concept of quantum pumping since its first proposal for a closed system. In this article, we review the studies which go beyond the conventional adiabatic approximation for open quantum systems to transfer energy quanta and electron spins with using the full counting statistics. We also discuss the recent developments of the nonadiabatic treatments of quantum pumping.

Acoustic and Perceptual Consequences of Speech Cues for Mandarin Speakers With Parkinson's Disease

PurposeThis study investigated the effects of cueing for increased loudness and reduced speech rate on scaled intelligibility and acoustics of speech produced by Mandarin speakers with hypokinetic dysarthria due to Parkinson's disease (PD).MethodEleven speakers with PD read passages in habitual, loud, and slow speaking conditions. Fifteen listeners rated ease of understanding (EOU) of the speech samples on a visual analog scale. Effects of the cues on EOU, vocal loudness, pitch range, pause duration and frequency, articulation rate, and vowel space, as well as relationships between EOU gains and acoustic features, were analyzed.ResultsEOU increased significantly in the loud condition only. The loud cue resulted in increased intensity, and the slow cue resulted both in reduced articulation rate and increased pause frequency. In the loud condition, EOU increased significantly as intensity increased and vowel centralization decreased. In the slow condition, EOU tended to increase as intensity increased and vowel centralization decreased but did not reach statistical significance.ConclusionCueing for loud speech may yield greater EOU gains than cueing for slow speech in Mandarin speakers with PD. Theoretical and clinical implications are discussed, although further investigations with more participants and a larger range of dysarthria severity are warranted.

Effect of Descent Velocity upon Muscle Activation and Performance in Two-Legged Free Weight Back Squats

Background: The aim of this study was to investigate the effect of descent velocity during two-legged full back squats upon muscle activation and squat ascent performance. Methods: Eleven healthy resistance-training males (age: 24 ± 6 years, body mass: 89.5 ± 21.5 kg, height: 1.84 ± 0.10 m) performed 4-repetition maximum (4-RM) two-legged full squats with slow, normal, and fast descent phases. Kinematics and muscle activity of ten muscles divided into five regions were measured. Results: The main findings were that maximal and minimal velocity were lower and maximal velocity occurred later in the slow condition, while there was no difference in second peak velocity or ascent displacement when compared with the normal and fast conditions. Furthermore, no differences in muscle activation were found as an effect of the descent velocity. Conclusion: It was concluded that the slow descent velocity had a negative effect upon the ascent phase, because of the lower peak velocity and peak force increasing the chance of failure. The lower velocities were not caused by lower pre-activation of the muscles but were probably a result of potentiation and/or utilization of stored elastic energy and/or the stretch reflex.

Predicting Intelligibility Gains in Individuals With Dysarthria From Baseline Speech Features

Purpose Across the treatment literature, behavioral speech modifications have produced variable intelligibility changes in speakers with dysarthria. This study is the first of two articles exploring whether measurements of baseline speech features can predict speakers’ responses to these modifications. Methods Fifty speakers (7 older individuals and 43 speakers with dysarthria) read a standard passage in habitual, loud, and slow speaking modes. Eighteen listeners rated how easy the speech samples were to understand. Baseline acoustic measurements of articulation, prosody, and voice quality were collected with perceptual measures of severity. Results Cues to speak louder and reduce rate did not confer intelligibility benefits to every speaker. The degree to which cues to speak louder improved intelligibility could be predicted by speakers' baseline articulation rates and overall dysarthria severity. Improvements in the slow condition could be predicted by speakers' baseline severity and temporal variability. Speakers with a breathier voice quality tended to perform better in the loud condition than in the slow condition. Conclusions Assessments of baseline speech features can be used to predict appropriate treatment strategies for speakers with dysarthria. Further development of these assessments could provide the basis for more individualized treatment programs.

Contrasting speed-accuracy tradeoffs for eye and hand movements reveal the optimal nature of saccade kinematics

In contrast to hand movements, the existence of a neural representation of saccade kinematics is unclear. Saccade kinematics is typically thought to be specified by motor error/desired displacement and generated by brain stem circuits that are not penetrable to voluntary control. We studied the influence of instructed hand movement velocity on the kinematics of saccades executed without explicit instructions. When the hand movement was slow the saccade velocity decreased, independent of saccade amplitude. We leveraged this modulation of saccade velocity to study the optimality of saccades (in terms of velocity and endpoint accuracy) in relation to the well-known speed-accuracy tradeoff that governs voluntary movements (Fitts’ law). In contrast to hand movements that obeyed Fitts' law, normometric saccades exhibited the greatest endpoint accuracy and lower reaction times, relative to saccades accompanying slow and fast hand movements. In the slow condition, where saccade endpoint accuracy suffered, we observed that targets were more likely to be foveated by two saccades resulting in step-saccades. Interestingly, the endpoint accuracy was higher in two-saccade trials, compared with one-saccade trials in both the slow and fast conditions. This indicates that step-saccades are a part of the kinematic plan for optimal control of endpoint accuracy. Taken together, these findings suggest normometric saccades are already optimized to maximize endpoint accuracy and the modulation of saccade velocity by hand velocity is likely to reflect the sharing of kinematic plans between the two effectors. NEW & NOTEWORTHY The optimality of saccade kinematics has been suggested by modeling studies but experimental evidence is lacking. However, we observed that, when subjects voluntarily modulated their hand velocity, the velocity of saccades accompanying these hand movements was also modulated, suggesting a shared kinematic plan for eye and hand movements. We leveraged this modulation to show that saccades had less endpoint accuracy when their velocity decreased, illustrating that normometric saccades have optimal speed and accuracy.

Estimation of Plastic and Creep Strain Development of SAC Solder under Cyclic Loading by Using Stepped Ramp Waves

The fatigue tests under both loading conditions of the Fast-Slow and the Slow-Fast were conducted to discuss validity of an inelastic strain analysis method which was proposed previously. The development behaviors of plastic and creep strains during the tests were analyzed by employing the stepped ramp wave (SW) loading. Using the analysis results, the difference of the development behaviors of plastic and creep strains between the Fast-Slow condition and the Slow-Fast condition was clarified. Then, the fatigue failure surfaces obtained from the tests were observed by using SEM to clarify the difference of the fracture surface between the Fast-Slow condition and the Slow-Fast condition. By correlating the aspect of fracture surface with the development behavior of plastic and creep strain, the validity of the proposed inelastic strain analysis method was discussed.

Support Vector Machine (SVM) For Toddler’s Nutritional Classification in Palu City

Abstract—Toddlers are groups who are vulnerable about the health nutrition problems. Nutritional status of children is one of the indicators that can describes the level of social welfare in the city. Nutritionists are the people that can determined the nutritional status. The problem that arises is the limited number of the nutrition experts in each area, this problem causes the children’s malnutrition in the Palu city is detected in very slow condition. The aims of this study is to help the health professionals in the health centers or the hospitals to determine the children’s nutritional status computerized, so the malnutrition problem in the Palu city can be detected earlier. Besides that, to help the government in policy making about nutrition of the toddlers in Palu city. This study uses a Support Vector Machine (SVM) which implemented in computer-based software application to analyze nutrition of the toddlers.Keywords—Nutrition, Software, Support Vector Machine (SVM), Toddlers, Palu city.

Speech rates converge in scripted turn-taking conversations

ABSTRACTWhen speakers engage in conversation, acoustic features of their utterances sometimes converge. We examined how the speech rate of participants changed when a confederate spoke at fast or slow rates during readings of scripted dialogues. A beat-tracking algorithm extracted the periodic relations between stressed syllables (beats) from acoustic recordings. The mean interbeat interval (IBI) between successive stressed syllables was compared across speech rates. Participants’ IBIs were smaller in the fast condition than in the slow condition; the difference between participants’ and the confederate's IBIs decreased across utterances. Cross-correlational analyses demonstrated mutual influences between speakers, with greater impact of the confederate on participants’ beat rates than vice versa. Beat rates converged in scripted conversations, suggesting speakers mutually entrain to one another's beat.