This study shows that the ratio of voice onset time (VOT) to syllable duration for /t/ and /d/ presents distributions with a stable boundary across speaking rates and that this boundary constitutes a perceptual criterion by which listeners judge the category affiliation of VOT. In Experiment 1, best-fit regression lines for VOT ratios of intervocalic /t/ and /d/ against speaking rate had zero slopes, and there was an inferable boundary between the distributions. In Experiment 2, listeners' identifications of syllableinitial stops conformed to this boundary ratio. In Experiment 3, VOT was held constant, while VOT ratios were altered by modifying the duration of the following vowel. As VOT ratios exceeded the boundary estimated from the data of Experiment 1, listeners' identifications shifted from /d/ to /t/. Timing relations in speech production can determine the identificationof voicing categoriesacross speaking rates.

BackgroundCaring for older patients can be challenging in the Emergency Department (ED). A > 12 hr ED stay could lead to incident episodes of delirium in those patients. The aim of this study was to assess the incidence and impacts of ED-stay associated delirium.MethodsA historical cohort of patients who presented to a Canadian ED in 2009 and 2011 was randomly constituted. Included patients were aged ≥ 65 years old, admitted to any hospital ward, non-delirious upon arrival and had at least a 12-hour ED stay. Delirium was detected using a modified chart-based Confusion Assessment Method (CAM) tool. Hospital length of stay (LOS) was log-transformed and linear regression assessed differences between groups. Adjustments were made for age and comorbidity profile.Results200 records were reviewed, 55.5% were female, median age was 78.9 yrs (SD:7.3). 36(18%) patients experienced ED-stay associated delirium. Nearly 50% of episodes started in the ED and within 36 hours of arrival. Comorbidity profile was similar between the positive CAM group and the negative CAM group. Mean adjusted hospital LOS were 20.5 days and 11.9 days respectively (p<.03).Conclusions1 older adult out of 5 became delirious after a 12 hr ED stay. Since delirium increases hospital LOS by more than a week, better screening and implementation of preventing measures for delirium could reduce LOS and overcrowding in the ED.

Studies that use measures of cerebro-acoustic coherence have shown that theta oscillations (3–10 Hz) entrain to syllable-size modulations in the energy envelope of speech. This entrainment creates sensory windows in processing acoustic cues. Recent reports submit that delta oscillations (<3 Hz) can be entrained by nonsensory content units like phrases and serve to process meaning—though such views face fundamental problems. Other studies suggest that delta underlies a sensory chunking linked to the processing of sequential attributes of speech sounds. This chunking associated with the “focus of attention” is commonly manifested by the temporal grouping of items in sequence recall. Similar grouping in speech may entrain delta. We investigate this view by examining how low-frequency oscillations entrain to three types of stimuli (tones, nonsense syllables, and utterances) having similar timing, pitch, and energy contours. Entrainment was indexed by “intertrial phase coherence” in the EEGs of 18 listeners. The results show that theta oscillations at central sites entrain to syllable-size elements in speech and tones. However, delta oscillations at frontotemporal sites specifically entrain to temporal groups in both meaningful utterances and meaningless syllables, which indicates that delta may support but does not directly bear on a processing of content. The findings overall suggest that, although theta entrainment relates to a processing of acoustic attributes, delta entrainment links to a sensory chunking that relates to a processing of properties of articulated sounds. The results also show that measures of intertrial phase coherence can be better suited than cerebro-acoustic coherence in revealing delta entrainment.

CLINICIAN'S CAPSULE What is known about the topic? Delirium is frequent in older inpatients but often goes undetected. A short tool, the 4 A's Test (4AT), was created and validated for the detection of delirium. What did this study ask? This study compared the performance of the French version of the 4AT (4AT-F) with the Confusion Assessment Method (CAM) for the screening of delirium. What did this study find? The 4AT-F was a fast and reliable screening tool for delirium in the emergency department (ED). Why does this study matter to clinicians? Because of its quick administration time, it allows for systematic screening of patients at risk of delirium and cognitive impairment.