Oral application of L-menthol in the heat: From pleasure to performance

When menthol is applied to the oral cavity it presents with a familiar refreshing sensation and cooling mint flavour. This may be deemed hedonic in some individuals, but may cause irritation in others. This variation in response is likely dependent upon trigeminal sensitivity toward cold stimuli, suggesting a need for a menthol solution that can be easily personalised. Menthol’s characteristics can also be enhanced by matching colour to qualitative outcomes; a factor which can easily be manipulated by practitioners working in athletic or occupational settings to potentially enhance intervention efficacy. This presentation will outline the efficacy of oral menthol application for improving time trial performance to date, either via swilling or via co-ingestion with other cooling strategies, with an emphasis upon how menthol can be applied in ecologically valid scenarios. Situations in which performance is not expected to be enhanced will also be discussed. An updated model by which menthol may prove hedonic, satiate thirst and affect ventilation will also be presented, with the potential performance implications of these findings discussed and modelled. Qualitative reflections from athletes that have implemented menthol mouth swilling in competition, training and maximal exercise will also be included

Leveraging EEG-based speech imagery brain-computer interfaces

Speech Imagery Brain-Computer Interfaces (BCIs) provide an intuitive and flexible way of interaction via brain activity recorded during imagined speech. Imagined speech can be decoded in form of syllables or words and captured even with non-invasive measurement methods as for example the Electroencephalography (EEG). Over the last decade, research in this field has made tremendous progress and prototypical implementations of EEG-based Speech Imagery BCIs are numerous. However, most work is still conducted in controlled laboratory environments with offline classification and does not find its way to real online scenarios. Within this thesis we identify three main reasons for these circumstances, namely, the mentally and physically exhausting training procedures, insufficient classification accuracies and cumbersome EEG setups with usually high-resolution headsets. We furthermore elaborate on possible solutions to overcome the aforementioned problems and present and evaluate new methods in each of the domains. In detail we introduce two new training concepts for imagined speech BCIs, one based on EEG activity during silently reading and the other recorded during overtly speaking certain words. Insufficient classification accuracies are addressed by introducing the concept of a Semantic Speech Imagery BCI, which classifies the semantic category of an imagined word prior to the word itself to increase the performance of the system. Finally, we investigate on different techniques for electrode reduction in Speech Imagery BCIs and aim at finding a suitable subset of electrodes for EEG-based imagined speech detection, therefore facilitating the cumbersome setups. All of our presented results together with general remarks on experiences and best practice for study setups concerning imagined speech are summarized and supposed to act as guidelines for further research in the field, thereby leveraging Speech Imagery BCIs towards real-world application.Speech Imagery Brain-Computer Interfaces (BCIs) bieten eine intuitive und flexible Möglichkeit der Interaktion mittels Gehirnaktivität, aufgezeichnet während der bloßen Vorstellung von Sprache. Vorgestellte Sprache kann in Form von Silben oder Wörtern auch mit nicht-invasiven Messmethoden wie der Elektroenzephalographie (EEG) gemessen und entschlüsselt werden. In den letzten zehn Jahren hat die Forschung auf diesem Gebiet enorme Fortschritte gemacht, und es gibt zahlreiche prototypische Implementierungen von EEG-basierten Speech Imagery BCIs. Die meisten Arbeiten werden jedoch immer noch in kontrollierten Laborumgebungen mit Offline-Klassifizierung durchgeführt und finden nicht denWeg in reale Online-Szenarien. In dieser Arbeit identifizieren wir drei Hauptgründe für diesen Umstand, nämlich die geistig und körperlich anstrengenden Trainingsverfahren, unzureichende Klassifizierungsgenauigkeiten und umständliche EEG-Setups mit meist hochauflösenden Headsets. Darüber hinaus erarbeiten wir mögliche Lösungen zur Überwindung der oben genannten Probleme und präsentieren und evaluieren neue Methoden für jeden dieser Bereiche. Im Einzelnen stellen wir zwei neue Trainingskonzepte für Speech Imagery BCIs vor, von denen eines auf der Messung von EEG-Aktivität während des stillen Lesens und das andere auf der Aktivität während des Aussprechens bestimmter Wörter basiert. Unzureichende Klassifizierungsgenauigkeiten werden durch die Einführung des Konzepts eines Semantic Speech Imagery BCI angegangen, das die semantische Kategorie eines vorgestellten Wortes vor dem Wort selbst klassifiziert, um die Performance des Systems zu erhöhen. Schließlich untersuchen wir verschiedene Techniken zur Elektrodenreduktion bei Speech Imagery BCIs und zielen darauf ab, eine geeignete Teilmenge von Elektroden für die EEG-basierte Erkennung von vorgestellter Sprache zu finden, um so die umständlichen Setups zu erleichtern. Alle unsere Ergebnisse werden zusammen mit allgemeinen Bemerkungen zu Erfahrungen und Best Practices für Studien-Setups bezüglich vorgestellter Sprache zusammengefasst und sollen als Richtlinien für die weitere Forschung auf diesem Gebiet dienen, um so Speech Imagery BCIs für die Anwendung in der realenWelt zu optimieren

Contribution of oxygen-dependent mechanisms to vascular responses of exercise in young and older men: the role of prostaglandins and adenosine

Previous work suggests vasodilating prostaglandins (PGs) are released during isometric handgrip exercise in an O$_2$-dependent manner in young men. This project investigates their contribution to the exercise hyperaemia of isometric and rhythmic handgrip contraction performed by healthy, recreationally-active young and older men. Hyperoxia (40% O$_2$), aspirin, and their combination equally attenuated exercise and post-exercise hyperaemia, and venous efflux of PGE$_2$ and PGI$_2$ in both age groups: efflux of these PGs was not attenuated with age, but their contribution to the hyperaemic response was. Further, the release of COX products evoked reflex vasoconstriction in an O$_2$-dependent manner. Moreover, 40% O$_2$, aspirin, and their combination equally inhibited the exercise-evoked vasoconstriction in both age groups. However, both the exercise-evoked attenuation in perfusion of resting skeletal muscles and the contribution of COX products were attenuated with age. Additional experiments showed that adenosine contributes to the hyperaemia of electrically evoked isometric twitch contractions in an O$_2$-dependent manner; adenosine may contribute to the increase in the concentrations of vasodilating PGs. Importantly, unlike 60% and 100% O$_2$, 40% O$_2$ did not attenuate acetylcholine-evoked endothelium-dependent dilatation in either age group, supporting the argument that the effect of 40% O$_2$ during exercise is independent of hyperoxia-related oxidative stress

The impact of a one-hour self-selected nap opportunity on physiological and performance variables during a simulated night shift

Napping has been explored extensively as a means of counteracting the negative effects associated with shift work. A significant amount of this research has focused on the implementation of scheduled naps, with few studies considering flexible nap schemes. The current study therefore aimed to assess the effects of a flexible nap opportunity on the physiological, cognitive, performance, neurophysiological and subjective responses of a group of non shift workers over the course of a three-day simulated night shift regime. Additional foci were the effects of the nap condition on the extent of the circadian adaptation of the subjects to the irregular work schedule and the circadian-related influences associated with being awake during the night. 36 subjects – 18 males and 18 females – were recruited to participate in the current study. The data collection spanned twelve days, during which four, three-day long shift cycles were set up: three night shift cycles and one day shift cycle. During each night shift cycle, three separate experimental conditions were staggered, namely the nap condition, the no nap condition and a booster break condition (a collaborative study that completed the setup). The day shift served as a further comparison. Each cycle comprised of 12 subjects, which meant there were four subjects per condition during each cycle. The shifts were 8 hours in duration, with the no nap group following a standard break schedule evinced in industry. The three breaks taken during the shifts amounted to a total time of 1 hour. The nap group was afforded a 1 hour flexible nap opportunity between 00h00 and 03h00 with no other breaks. Therefore, both conditions had the same amount of work time. During the shifts, subjects performed two simple, low arousal tasks (beading and packing) and completed a test battery roughly every two hours which was comprised of physiological, performance, neurophysiological and subjective measures. It was found that the inclusion of the nap opportunity significantly improved output performance and response time during a low precision, modified Fitts tapping task over the course of three night shifts, relative to no napping. Physiologically, napping resulted in higher heart rate frequency measures by the end of the shifts, which were also accompanied by significant reductions in subjective sleepiness ratings during all iii the night shifts. The nap group’s responses in this case, did not differ significantly from those of the day shift. Both simple reaction time and memory performances improved as a result of the nap inclusion, but only during the third night shift. The majority of the measures included in the research also depicted the effects of the circadian rhythm, which was indicative of the pronounced effect that this natural biological down regulation has on performance during the night. Napping reduced the severity of these effects during beading performance and measures of subjective sleepiness. With regard to habituation, the nap opportunity also resulted in positive changes in the responses of beading performance, high precision response time, simple reaction time and both subjective sleepiness measures, relative to no napping. Sleep diary responses indicated that although sleep length and quality during the day were significantly reduced for both night-time conditions, recovery sleep (length and quality) for the nap group did not differ significantly from the no nap group. The findings of this research indicate that the inclusion of a flexible napping opportunity during the night shift had positive effects on some physiological, performance and subjective responses, and that this intervention is as beneficial as scheduled napping. Specifically, napping resulted in a significantly higher output during the beading task, relative to the no nap group despite the duration of work time being the same. As such the introduction of a flexible, self-selected nap opportunity is a practical, effective and individual-specific means of alleviating the negative effects of shift work, while improving certain performance parameters. Therefore, industries should consider its inclusion in their fatigue management programs. However, contextspecific considerations must be made, with regard work scheduling, individual differences and task demands when implementing such an intervention. This will ensure that its introduction will be well received and in time, lessen the health and work-related decrements associated with shift work

Worker and Public Health and Safety

This book on "Worker and Public Health and Safety: Current Views" brings together current scholarly work and opinions in the form of original papers and reviews related to this field of study. It provides important and recent scientific reading as well as topical medical and occupational information and research in areas of immediate relevance, such as chronic and occupational diseases, worker safety and performance, job strain, workload, injuries, accident and errors, risks and management, fitness, burnout, psychological and mental disorders including stress, therapy, job satisfaction, musculoskeletal symptoms and pain, socio-economic factors, dust pollution, pesticides, noise, pathogens, and related areas

Novel Techniques to Measure the Sensory, Emotional, and Physiological (Biometric) Responses of Consumers toward Foods and Packaging

This book reprinted from articles published in the Special Issue “Novel Techniques to Measure the Sensory, Emotional, and Physiological (Biometric) Responses of Consumers toward Foods and Packaging” of the journal Foods aims to provide a deeper understanding of novel techniques to measure the different sensory, emotional, and physiological responses toward foods. The editor hopes that the findings from this Special Issue can help the broader scientific community to understand the use of novel sensory science techniques that can be used in the evaluation of products

Emotion and Stress Recognition Related Sensors and Machine Learning Technologies

This book includes impactful chapters which present scientific concepts, frameworks, architectures and ideas on sensing technologies and machine learning techniques. These are relevant in tackling the following challenges: (i) the field readiness and use of intrusive sensor systems and devices for capturing biosignals, including EEG sensor systems, ECG sensor systems and electrodermal activity sensor systems; (ii) the quality assessment and management of sensor data; (iii) data preprocessing, noise filtering and calibration concepts for biosignals; (iv) the field readiness and use of nonintrusive sensor technologies, including visual sensors, acoustic sensors, vibration sensors and piezoelectric sensors; (v) emotion recognition using mobile phones and smartwatches; (vi) body area sensor networks for emotion and stress studies; (vii) the use of experimental datasets in emotion recognition, including dataset generation principles and concepts, quality insurance and emotion elicitation material and concepts; (viii) machine learning techniques for robust emotion recognition, including graphical models, neural network methods, deep learning methods, statistical learning and multivariate empirical mode decomposition; (ix) subject-independent emotion and stress recognition concepts and systems, including facial expression-based systems, speech-based systems, EEG-based systems, ECG-based systems, electrodermal activity-based systems, multimodal recognition systems and sensor fusion concepts and (x) emotion and stress estimation and forecasting from a nonlinear dynamical system perspective

Effects of circadian rhythm phase alteration on physiological and psychological variables: Implications to pilot performance (including a partially annotated bibliography)

The effects of environmental synchronizers upon circadian rhythmic stability in man and the deleterious alterations in performance and which result from changes in this stability are points of interest in a review of selected literature published between 1972 and 1980. A total of 2,084 references relevant to pilot performance and circadian phase alteration are cited and arranged in the following categories: (1) human performance, with focus on the effects of sleep loss or disturbance and fatigue; (2) phase shift in which ground based light/dark alteration and transmeridian flight studies are discussed; (3) shiftwork; (4)internal desynchronization which includes the effect of evironmental factors on rhythmic stability, and of rhythm disturbances on sleep and psychopathology; (5) chronotherapy, the application of methods to ameliorate desynchronization symptomatology; and (6) biorythm theory, in which the birthdate based biorythm method for predicting aircraft accident susceptability is critically analyzed. Annotations are provided for most citations