Accentism on Trial: Categorization/Stereotyping and Implicit Biases Predict Harsher Sentences for Foreign-Accented Defendants

In this study, participants were presented with two tasks: the Implicit Association Test (IAT), and a mock trial task. In both tasks, the auditory stimuli were produced by native or foreign-accented speakers, and presented either free of noise or mixed with background white noise, to estimate the role of processing fluency on jurors’ appraisals. In the IAT, participants showed positive implicit biases toward native speech, and negative implicit biases toward foreign-accented speech. In the mock trial task, participants gave much harsher sentences to the foreign-accented than native defendant, but only when defendants’ statements were free of noise. Moreover, we found that participants’ implicit biases were a relevant predictor of the sentences they gave to the defendants. Our results suggest that categorization/stereotyping is the main mechanism responsible for the effect of defendants’ accents on jurors’ appraisals, and that members of an estimated group who violate social norms are punished more severely.

Constant Resting Frequency and Auditory Midbrain Neuronal Frequency Analysis of Hipposideros pratti in Background White Noise

Acoustic communication signals are inevitably challenged by ambient noise. In response to noise, many animals adjust their calls to maintain signal detectability. However, the mechanisms by which the auditory system adapts to the adjusted pulses are unclear. Our previous study revealed that the echolocating bat, Hipposideros pratti, increased its pulse intensity in the presence of background white noise. In vivo single-neuron recording demonstrated that the auditory midbrain neurons tuned to the second harmonic (H2 neurons) increased their minimal threshold (MT) to a similar degree as the increment of pulse intensity in the presence of the background noise. Furthermore, the H2 neurons exhibited consistent spike rates at their best amplitudes and sharper intensity tuning with background white noise compared with silent conditions. The previous data indicated that sound intensity analysis by auditory midbrain neurons was adapted to the increased pulse intensity in the same noise condition. This study further examined the echolocation pulse frequency and frequency analysis of auditory midbrain neurons with noise conditions. The data revealed that H. pratti did not shift the resting frequency in the presence of background noise. The auditory midbrain neuronal frequency analysis highly linked to processing the resting frequency with the presence of noise by presenting the constant best frequency (BF), frequency sensitivity, and frequency selectivity. Thus, our results suggested that auditory midbrain neuronal responses in background white noise are adapted to process echolocation pulses in the noise conditions.

Background white noise and speech facilitate visual working memory

In contrast to background white noise, the detrimental effects of background speech on verbal working memory (WM) were often explained by speech interference in the same verbal modality. Yet, those results were confounded with potential differences between arousal levels induced by speech and white noise. To address the role of arousal, in the present study, we minimized the verbal interference and used a visual WM task to test the influence of background speech or white noise. Electrodermal activity (EDA) and Electromyography (EMG) were recorded simultaneously to indicate the arousal levels of participants. Results showed that both background speech and white noise significantly improved visual WM performance. The change of performance further correlated with the change of physiological signals linked with arousal. Taken together, our results suggest that both background speech and white noise facilitate visual WM through raising the arousal level.

PHOTOACOUSTIC SIGNALS DENOISING BASED ON EMPIRICAL MODE DECOMPOSITION AND ENERGY-WINDOW METHOD

In the process of photoacoustic imaging (PAI), the photoacoustic signals are polluted by a strong background white noise, which is caused by many factors such as the system thermal noise or short noise, the tissue reflecting or scattering interference, and the impedance match lack between the transducer and tissue. The inevitable noise can degrade the contrast sensitivity of photoacoustic images seriously. In this paper, based on the energy window, a CMSE-EMD denoising method is employed to photoacoustic image reconstruction. Results of the simulation demonstrate that it can eliminate the image artifacts more effectively and achieve great improvement in image quality.

Masking, Temporal Integration, and Sensorineural Hearing Loss

This study was undertaken basically to examine the effect of white noise masking on temporal integration and how the frequency dependence of temporal integration is related to hearing loss. The threshold differences between 500-msec and 20-msec at .5, 1, 2, and 4 kHz were found for 147 ears of 86 subjects with normal hearing and with various amounts of cochlear hearing loss. Thresholds were measured in three levels of background white noise—30, 60, and 90 dB SPL. The principal finding was that temporal integration is frequency dependent and this dependence is not an epiphenomenon of the decrease in temporal integration due to cochlear hearing loss.

Maximum Entropy Spectral Analysis – Some Comments

Study of a model data analysis situation with the help of computer experiments reveals that the Maximum Entropy Method of Spectral Analysis owes its popularity to a peak-sharpening property which is found to be a strong function of the level of background white noise present in the spectrum. In one limit, misleading results may be obtained by this technique. Some suggestions for a more fruitful use of the technique are made.