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Four signal-detection experiments demonstrated robust stimulus-driven, or exogenous, attentional processes in selective frequency listening. Detection of just-above-threshold signal tones was consistently better when the, signal matched the frequency of an uninformative cue tone, even with relatively long cue-signal delays (Experiment 1) or when as few as 1 in 8 signals were at the cued frequency (Experiment 2). Experiments 3 and 4 compared performance with informative and uninformative cues. The involvement of intentional, or endogenous, processes was found to only slightly increase the size of the cuing effect beyond that evident with solely exogenous processes, although the attention band, a measure of how narrowly attention is focused, was found to be wider when cues were informative. The implications for models of auditory attention are discussed.

Three important forms of information available to the listener may be identified in any auditory warning: what (semantic), where (location) and when (perceived urgency). Each form is addressed in the present design study of auditory warning pulses. Recordings were made via a dummy head, and were presented dichotically to listeners in a left/right localization task. The first experiment identified a suitable notched noise component for providing location information in the pulse stimulus. The second experiment required participants to simultaneously identify a distinct tonal signature and the location of the sound when they were presented with one of three tonal types, or one of three compound (tone plus noise) stimuli. Response accuracy and response latency for this identification and localization task were significantly better with the compound than with tone alone stimuli. Perceived urgency of compound complex tone plus noise stimuli was investigated in the third experiment. While there may be a trade-off between localization acuity and perceived urgency, the addition of noise components to the auditory warning pulse was shown to enhance the location information available to the listener. It is suggested that some auditory warning designs will benefit from the simultaneous provision of what and where forms of information in the sounds.

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Obesity, diabetes and metabolic disease represent an ongoing and rapidly worsening public health issue in both the developed, and much of the developing world. Although there are many factors that influence fat storage, it has been clearly demonstrated that the homeostatic cornerstone of metabolism lies within the hypothalamus. Moreover, neuronal damage to vital areas of the hypothalamus can drive reregulation or dysregulation of endocrine function, energy expenditure and appetite, thereby promoting a shift in overall metabolic function towards a state of obesity. Therefore, identification of treatments that influence the hypothalamus to improve obesity and associated metabolic diseases has long been a medical goal. Interestingly, evidence from animal studies suggests that activating the vestibular system, specifically the macular gravity receptor, influences the hypothalamus in a way that decreases body fat storage and causes a metabolic shift towards a leaner state. Given that the macular element of the vestibular system has been shown to activate with transdermal electrical stimulation applied to the mastoids, this may be a potential therapeutic approach for obesity, diabetes or related metabolic diseases, whereby repetitive stimulation of the vestibular system influences hypothalamic control of metabolic homeostasis, thereby encouraging decreased fat storage. Here, we present an up‐to‐date review of the current literature surrounding the vestibular influence of the hypothalamus and associated homeostatic sites in the context of current and novel therapeutic approaches for improved clinical management of obesity and diabetes.

Human listeners perform well when identifying both members of simultaneous steady-state vowel pairs, even when the vowels start and stop at the same time, are presented monaurally, have approximately equal intensities, and have the same fundamental frequency (f0). The sensation described by listeners is of one dominant, vowel "colored" by the second, less easily identified, or nondominant vowel. Introducing a small separation in f0 between the vowels improves performance and listeners now report that there is a sensation of two voice sources rather than one. It has been suggested that listeners use an f0-guided segregation strategy in identifying two vowels that differ in f0. An experiment is reported in which four listeners attempted to identify both members of a pair of concurrent vowels which varied in duration from a single cycle of the stimulus waveform (one pitch period) up to eight cycles. A dominant vowel was identified with near 100% accuracy even in the single-cycle condition, whereas identification of the nondominant vowel showed a slow improvement up to eight cycles. A difference in f0 between the vowels improved identification of the nondominant vowel, but between three and four cycles of the vowels were necessary for this advantage. It is first concluded that the improvement in performance with stimulus duration is due to an improvement in identification of the nondominant vowel; and, second, a difference in f0 is not required for segregation of the dominant vowel which is available from stimuli which are too brief to provide a useful estimate of f0.

ObjectivesElectrical stimulation of the vestibular system (VeNS) has been shown to improve Insomnia Severity Index (ISI) when delivered during sleep. We hypothesize that repeated electrical vestibular stimulation, when delivered prior to sleep onset, will improve ISI scores. The primary aim of this study was to assess the effect that VeNS had on ISI scores when delivered prior to sleep onset. A secondary aim was to provide initial data indicating “length of time to effect” that will allow more appropriate design of a larger randomized control trial (RCT).MethodsThe present study was an experimental study (pre and post without control). The participants acted as self-controls. After recording the baseline values, electrical vestibular nerve stimulation was administered as intervention once in a day for 30 min, 1 h prior to sleep onset using ML1000 device (Neurovalens, UK) for 14 days.ResultsThere was significant decrease in the ISI scores followed by the electrical vestibular nerve stimulation. Further, participants reported a significant increase in well-rested sleep post the intervention period.ConclusionsThis study supports our hypothesis that VeNS has a positive impact on ISI scores when delivered on a regular basis prior to sleep onset.