Repetitive episodic hypoxia every 30 sec administered chronically to Sprague-Dawley (SD) rats has been shown by previous studies to cause a sustained increase in daytime blood pressure (BP). Acoustic arousal in humans during wake or sleep produces an acute BP rise. The question then arises as to whether chronic episodic acoustic arousal applied with the same frequency and duration as episodic hypoxia induces elevated BP. We exposed 14-week-old (N = 10) SD rats in individual cages to recurrent buzzer noise (500 Hz, 100 dB) 6 out of every 30 sec, 7 h/day for 35 days. Ten other rats were placed in similar cages daily but not exposed to noise, to provide a sham condition. An infrared beam with a detector was positioned at the end of each cage. This allowed us to quantify motion by registering the number of times the rat broke the beam per 7 h period. Mean intraarterial BP was measured in unrestrained conscious animals at baseline and at the end of 35 days of their respective conditions. Acute episodic acoustic stimulation caused an immediate response in BP and heart rate. Habituation occurred in that the movement response to 120 noises per hour was 75% in hour one and 20% in hours two through seven on day one. The movement response was further reduced by day 35 but remained significantly higher than in animals not stimulated by noise. The cardiovascular response to noise also showed signs of habituation. Chronic noise stimulation produced no sustained increases in BP after 35 days of exposure.
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http://dx.doi.org/10.1016/s0895-7061(99)00032-1 | DOI Listing |
Eur J Neurosci
January 2025
Department of Psychology, University of Lübeck, Lübeck, Germany.
Distraction is ubiquitous in human environments. Distracting input is often predictable, but we do not understand when or how humans can exploit this predictability. Here, we ask whether predictable distractors are able to reduce uncertainty in updating the internal predictive model.
View Article and Find Full Text PDFTrends Hear
January 2025
Bionics Institute, East Melbourne, VIC, Australia.
This study used functional near-infrared spectroscopy (fNIRS) to measure aspects of the speech discrimination ability of sleeping infants. We examined the morphology of the fNIRS response to three different speech contrasts, namely "Tea/Ba," "Bee/Ba," and "Ga/Ba." Sixteen infants aged between 3 and 13 months old were included in this study and their fNIRS data were recorded during natural sleep.
View Article and Find Full Text PDFJ Acoust Soc Am
January 2025
USC Viterbi School of Engineering, University of Southern California, Los Angeles, California 90089-1455, USA.
Voice quality serves as a rich source of information about speakers, providing listeners with impressions of identity, emotional state, age, sex, reproductive fitness, and other biologically and socially salient characteristics. Understanding how this information is transmitted, accessed, and exploited requires knowledge of the psychoacoustic dimensions along which voices vary, an area that remains largely unexplored. Recent studies of English speakers have shown that two factors related to speaker size and arousal consistently emerge as the most important determinants of quality, regardless of who is speaking.
View Article and Find Full Text PDFBehav Res Methods
January 2025
College of Psychology, Liaoning Normal University, No. 850 Huanghe Road, Dalian, 116029, Liaoning, China.
Nonverbal emotional vocalizations play a crucial role in conveying emotions during human interactions. Validated corpora of these vocalizations have facilitated emotion-related research and found wide-ranging applications. However, existing corpora have lacked representation from diverse cultural backgrounds, which may limit the generalizability of the resulting theories.
View Article and Find Full Text PDFWhile research on auditory attention in complex acoustical environment is a thriving field, experimental studies thus far have typically treated participants as passive listeners. The present study-which combined real-time covert loudness manipulations and online probe detection-investigates for the first time to our knowledge, the effects of acoustic salience on auditory attention during live interactions, using musical improvisation as an experimental paradigm. We found that musicians were more likely to pay attention to a given co-performer when this performer was made sounding louder or softer; that such salient effect was not owing to the local variations introduced by our manipulations but rather likely to be driven by the more long-term context; and that improvisers tended to be more strongly and more stably coupled when a musician was made more salient.
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