Publications by authors named "Stephen Hedger"

To understand differences in anti-factor-Xa levels produced by two different dosing strategies (conventional and individualized) for therapeutic enoxaparin in a cohort of hospital inpatients. A multicenter, retrospective cohort study over a two- and a half-year period for inpatients with stable renal function and on therapeutic enoxaparin. Anti-factor-Xa levels were taken 3-5 h after enoxaparin administration and a minimum of 48 h of dosing.

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Tonal short-term memory has been positively associated with both incidentally acquired absolute pitch memory (e.g., for popular songs) and explicitly learned absolute pitch (AP) categories; however, the relationship between these constructs has not been directly tested within the same individuals.

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Previous studies have reported visual motion aftereffects (MAEs) following prolonged exposure to auditory stimuli depicting motion, such as ascending or descending musical scales. The role of attention in modulating these cross-modal MAEs, however, remains unclear. The present study manipulated the level of attention directed to musical scales depicting motion and assessed subsequent changes in MAE strength.

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Article Synopsis
  • Musical training does not seem to enhance the neural processing of sounds, contradicting earlier smaller studies that suggested otherwise.
  • A large-scale study with over 260 participants found no significant correlation between musical training and neural responses to speech sounds.
  • The research indicates a lack of evidence for neural plasticity in early auditory responses tied to musical training and exposure.
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Objectives: Persistent and significant swallowing impairment can occur in individuals with dementia. Determining prognosis and establishing realistic goals of care in this population is complex and comfort feeding may be recommended. This study aimed to establish evidence relating to patient outcomes following recommendation of comfort feeding to aid informed decision making.

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Article Synopsis
  • Most people, even without formal music training, can accurately remember pitches in familiar songs, but their accuracy can vary.
  • A study with 108 participants found connections between singing accuracy, tonal short-term memory (STM), and absolute pitch memory (APM), confirming earlier research.
  • The results showed that tonal STM and singing accuracy are linked, and that tonal STM fully mediates the relationship between APM and singing accuracy, supporting models that explain how we match pitches vocally.
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  • Statistical learning enables individuals to detect patterns in their environment, and prior studies indicate that this ability is more effective for speech than for non-speech stimuli, hinting at a natural predisposition for language.
  • The study investigated whether this advantage for speech is due to acoustic features rather than subjective perception by examining participants' responses to ambiguous sine-wave speech (SWS) perceived either as speech or non-speech.
  • Results showed that while participants could detect individual syllables better when perceiving SWS as speech, their overall ability to extract patterns from the sounds was unaffected by whether they perceived them as speech-like or not, suggesting that statistical learning functions automatically and is driven by the stimuli rather than linguistic context.
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Most listeners can determine when a familiar recording of music has been shifted in musical key by as little as one semitone (e.g., from B to C major).

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Absolute pitch (AP) is the rare ability to name any musical note without the use of a reference note. Given that genuine AP representations are based on the identification of isolated notes by their tone chroma, they are considered to be invariant to (1) surrounding tonal context, (2) changes in instrumental timbre, and (3) changes in octave register. However, there is considerable variability in the literature in terms of how AP is trained and tested along these dimensions, making recent claims about AP learning difficult to assess.

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Spoken language contains overlapping patterns across different levels, from syllables to words to phrases. The discovery of these structures may be partially supported by statistical learning (SL), the unguided, automatic extraction of regularities from the environment through passive exposure. SL supports word learning in artificial language experiments, but few studies have examined whether it scales up to support natural language learning in adult second language learners.

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The COVID-19 pandemic notably altered adolescent substance use during the initial stage (Spring 2020) of the pandemic. The purpose of this longitudinal study is to examine trajectories of adolescent substance use across the pandemic and subsequent periods of stay-at-home orders and re-opening efforts. We further examined differences as a function of current high school student versus graduate status.

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The ability to generalize across specific experiences is vital for the recognition of new patterns, especially in speech perception considering acoustic-phonetic pattern variability. Indeed, behavioral research has demonstrated that listeners are able via a process of generalized learning to leverage their experiences of past words said by difficult-to-understand talker to improve their understanding for new words said by that talker. Here, we examine differences in neural responses to generalized versus rote learning in auditory cortical processing by training listeners to understand a novel synthetic talker.

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Most listeners have an implicit understanding of the rules that govern how music unfolds over time. This knowledge is acquired in part through statistical learning, a robust learning mechanism that allows individuals to extract regularities from the environment. However, it is presently unclear how this prior musical knowledge might facilitate or interfere with the learning of novel tone sequences that do not conform to familiar musical rules.

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The frequency-following response (FFR) provides a measure of phase-locked auditory encoding in humans and has been used to study subcortical processing in the auditory system. While effects of experience on the FFR have been reported, few studies have examined whether individual differences in early sensory encoding have measurable effects on human performance. Absolute pitch (AP), the rare ability to label musical notes without reference notes, provides an excellent model system for testing how early neural encoding supports specialized auditory skills.

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Background: Recent studies cast doubt on the net effect of antipsychotics for delirium.

Aim: To investigate the influence of these studies and other factors on clinicians' delirium treatment practice and practice change in palliative care and other specialties using the Theoretical Domains Framework.

Design: Australia-wide online survey of relevant clinicians.

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The artery of Percheron (AOP) is a rare arterial variant of the thalamic blood supply. Due to the densely packed collection of nuclei it supplies, an infarction of the AOP can be devastating. Here we highlight a patient who had an AOP stroke in the community, which was initially managed as cardiac arrest.

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Many human behaviors are discussed in terms of discrete categories. Quantizing behavior in this fashion may provide important traction for understanding the complexities of human experience, but it also may bias understanding of phenomena and associated mechanisms. One example of this is absolute pitch (AP), which is often treated as a discrete trait that is either present or absent (i.

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Adjusting to the vocal characteristics of a new talker is important for speech recognition. Previous research has indicated that adjusting to talker differences is an active cognitive process that depends on attention and working memory (WM). These studies have not examined how talker variability affects perception and neural responses in fluent speech.

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Absolute pitch (AP), the rare ability to name any musical note without the aid of a reference note, is thought to depend on an early critical period of development. Although recent research has shown that adults can improve AP performance in a single training session, the best learners still did not achieve note classification levels comparable to performance of a typical, "genuine" AP possessor. Here, we demonstrate that these "genuine" levels of AP performance can be achieved within eight weeks of training for at least some adults, with the best learner passing all measures of AP ability after training and retaining this knowledge for at least four months after training.

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Interactions with natural environments and nature-related stimuli have been found to be beneficial to cognitive performance, in particular on executive cognitive tasks with high demands on directed attention processes. However, results vary across different studies. The aim of the present paper was to evaluate the effects of nature vs.

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Article Synopsis
  • - People enjoy sounds from nature, like a flowing stream or birds singing, for positive experiences, but it's unclear if this enjoyment is due to the sounds' qualities or because of their association with beauty in nature.
  • - A study showed that when people struggled to recognize nature sounds, their preference for those sounds decreased, and this preference was affected by how easily they could identify the sounds.
  • - In a follow-up experiment, even difficult-to-identify sounds categorized as nature still evoked a strong preference, highlighting that recognizing sounds as natural significantly shapes our aesthetic liking, rather than the sounds' acoustic qualities themselves.
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Action and perception interact in complex ways to shape how we learn. In the context of language acquisition, for example, hand gestures can facilitate learning novel sound-to-meaning mappings that are critical to successfully understanding a second language. However, the mechanisms by which motor and visual information influence auditory learning are still unclear.

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Attention restoration theory (ART) posits that stimuli found in nature may restore directed attention functioning by reducing demands on the endogenous attention system. In the present experiment, we assessed whether nature-related cognitive benefits extended to auditory presentations of nature, a topic that has been understudied. To assess directed attention, we created a composite measure consisting of a backward digit span task and a dual n-back task.

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By definition, individuals with absolute pitch (AP) can categorize with near perfect accuracy without a reference pitch. This definition implies a uniformity of performance across people; however, in reality AP is a complex, multidimensional ability, shaped by both early and recent auditory experiences. In the present study we assess whether AP possessors' accuracy for identifying isolated notes is more distributed when judging more challenging instrumental timbres and octaves, as well as whether variability in note categorization could be explained through individual differences in musical expertise, language background, or working memory.

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