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Effect of Noise Exposure on Human Auditory Function: Hidden Versus Not-So-Hidden Hearing Loss
Published in Stavros Hatzopoulos, Andrea Ciorba, Mark Krumm, Advances in Audiology and Hearing Science, 2020
As reviewed by Bramhall et al. (2019), there are a variety of electrophysiological and psychophysical tools that are currently being evaluated for potential use detecting “hidden hearing loss” in humans; here, we use quotes to reflect the nonspecific nature of this term, as each of these proposed tests captures either a change in sound-evoked neural responses, or a change in sensitivity to some acoustic cue presented in a behavioral detection task. The various proposed evoked potential assessments include the envelope following response (EFR) (Paul et al., 2017; Shaheen et al., 2015), middle ear muscle reflex (Valero et al., 2016), ABR Wave-V latency changes during forward masking (Mehraei et al., 2017), normalizing the amplitude of ABR Wave-I relative to the amplitude of ABR Wave-V (a measure of central response that does not appear to be affected by synaptopathy) (Verhulst et al., 2016), and normalizing the amplitude of the action potential relative to the amplitude of the summating potential (i.e., SP/AP ratio) (Liberman et al., 2016). With respect to behavioral tasks, there are suggestions to consider psychophysical manipulation of amplitude modulation in detection tasks (Paul et al., 2017), and binaural detection ability (Bernstein et al., 2016). The lack of agreed on metrics is widely agreed to be a major issue for progress in understanding the effects of noise on human hearing (Hickox et al., 2017; Kobel et al., 2017; Le Prell and Lobarinas, 2015; Liberman and Kujawa, 2017).
Taste and smell
Published in Patrick Rabbitt, The Aging Mind, 2019
Many studies of losses of taste in old age have tested sensitivity for single chemical compounds to discover both what is the weakest concentration we can detect and, above this threshold level, what are the smallest differences that we can notice: the just-noticeable differences (jnds) that are the grist of studies in sensory psychophysics. Other issues are the relative sizes of differences that we can detect when a chemical is presented on its own, in water or is masked by other flavours in a compound of other substances.
The Physiology of Pain
Published in Bernard J. Dalens, Jean-Pierre Monnet, Yves Harmand, Pediatric Regional Anesthesia, 2019
Bernard Jacques Dalens, Brigitte Storme
Pain is a pure sensory experience, quite universal and known to every present or ancient civilization, but which has no satisfactory definition. The International Association for the Study of Pain described pain as “an unpleasant sensory and emotional experience associated with actual or potential tissue damage, or described in terms of such damage”.1 (Such a definition is appropriate for acute pain, but does not necessarily apply to chronic pain.) Psychophysical studies have been especially fruitful in exploring such sensory experiences as hearing or sight, but investigation of pain has not produced as meaningful results, even though the concept of pain has become much more precisely delineated.
Line‐by‐line visual acuity scoring equivalence with letter‐by‐letter visual acuity scoring
Published in Clinical and Experimental Optometry, 2022
With regard to classic psychophysical threshold criterion, typically a frequency-of-seeing of 50% is chosen as threshold. Correcting for guessing given the possible number of alternatives, as in a force-choice methodology, psychophysicists would set the threshold at a frequency-of-seeing anywhere between 50-75% (that is ranging from an impractical infinite number of choices to only two alternatives). Clinicians apply this more simply to line visual acuity by setting a criterion of the ‘slightest majority of the line’ (for example, three-or-more on a line when five letters on a line are present). The findings in this study validate this general clinical rule. Specifically in this study, it was found that using a 60% correct criterion (three out of five) was the line acuity criterion that most closely matched the gold standard letter-by-letter scoring criterion.
The perceptual limitations of troubleshooting hearing-aids based on patients’ descriptions
Published in International Journal of Audiology, 2021
Benjamin Caswell-Midwinter, William M. Whitmer
Gain, the fundamental hearing-aid parameter for restoring audibility, is routinely adjusted towards prescribed targets in real-ear verification and away from targets to personalise fittings using patient feedback (Anderson, Arehart, and Souza 2018; Jenstad, Van Tasell, and Ewert 2003; Kuk and Ludvigsen 1999; Thielemans et al. 2017). Gain can also be adjusted by patients themselves in self-fitting devices (Keidser and Convery 2016; Nelson et al. 2018; Sabin et al. 2020). Given this, the authors previously measured discrimination thresholds (just-noticeable differences: JNDs) for gain adjustments. The JNDs measured with speech-shaped noises were approximately 3 dB for increments of octave-band width (0.5 − 4 kHz) and 1.5 dB for broadband increments (Caswell-Midwinter and Whitmer 2019a), providing a psychophysical baseline for gain adjustments in clinical practice. Compared to steady-state noise, the JNDs measured with male, single-talker sentences were larger, the more so the narrower the bandwidth being adjusted; 6–10 dB for octave-band increments, 4–7 dB for wideband increments, and 2 dB for broadband increments (Caswell-Midwinter and Whitmer 2019b). The scale of these JNDs is partly explained by the sparseness of energy in any one frequency band at any given time in sentences. These JNDs indicate the limitations of using short sentences as the stimulus for adjusting gain in response to patient feedback.
Number Magnitude Processing and Verbal Working Memory in Children with Mild Intellectual Disabilities
Published in Developmental Neuropsychology, 2020
Ulf Träff, Anna Levén, Rickard Östergren, Daniel Schöld
This task was administered using the Panamath software (v.1.21; Halberda & Feigenson, 2008). Two arrays, each containing between 5–21 blue and yellow dots, were presented on the screen. The task was to determine which one of the two arrays had more dots, as rapidly as possible without making an error. The child responded by pressing the A key or L key. The child had to press the space bar to present the next trial. Prior to each trial, a fixation cross was displayed in the middle of the screen. Four ratios (1.28; 1.46; 1.75; 2.75) were presented 12 times each, resulting in 48 trials. Surface area varied on half the trials, along with dot size. This was to control for confounding variables and ensure attention to numerosity. The software registered accuracy and response time for each trial and calculated a Weber fraction (w), as an estimate of ANS acuity, which is based on accuracy for each of the four different ratios. The w is calculated by using Weber’s law ((A-B)/B where A and B are the quantities being compared) as it has been found that ANS acuity adheres to psychophysical laws and thus, can be understood in terms of Weber’s law. The w is an index of how much two sets of objects needs to differ so that an individual can reliably notice a difference between them (Halberda & Feigenson, 2008; Libertus, Feigenson, & Halberda, 2011).