Hindi Audio The Awakening
The feeling of grogginess and lack of alertness one may experience upon, and post-awakening is a physiological phenomenon termed 'sleep inertia' [1-3]. Compared to wholly awake participants, individuals experiencing sleep inertia show decrements in performance which can be reflected in significantly poorer accuracy, memory, complex decision making, and slower reaction time (RT). The duration and severity of sleep inertia is variable and can be influenced by factors such as sleep stage at awakening, sleep deprivation, time of day, as well as a variety of reactive countermeasures  like caffeine [5-7] or lighting treatments [8-10]. Research suggests that a typical bout of sleep inertia may last for approximately 30 minutes, however, durations of up to 4 hours have also been reported [1,11-15]. Indeed, in many scenarios sleep inertia represents a multidimensional performance decrement that has the proven potential to negatively impact real-world situations and is frequently highlighted as a research field requiring improved understanding to allay such occurrences [16-23]. For example, in the 2010 Air India Express air crash disaster that resulted in 158 fatalities, it has been shown that the captain of the aircraft had recently woken from an in-flight nap prior to the accident. The poor decisions made by the pilot in the time-frame from awakening to crashing were attributed to the disaster and have been linked to the effects of sleep inertia . Tragedies such as this highlight the importance of maintaining situational awareness in demanding and critical settings. In everyday scenarios, the impacts of sleep inertia cannot be underestimated. It is estimated that on a global economic scale the financial losses as a result of sleep deprivation (a known factor to enhance sleep inertia) amount to hundreds of billions of dollars annually [24,25]. Thus, countermeasure treatments for the reduction of sleep inertia are warranted to ensure safety among citizens in public space, domestic, and employment settings.
Hindi Audio The Awakening
One emerging practical and efficient field which explores techniques to neutralize the effects of sleep inertia is the study of auditory countermeasures . Auditory research seeks to understand if treatments sounded pre, and post-awakening may counteract sleep inertia, and is grounded in psychophysics research on auditory perception and cognition. It has been well appreciated for some time that sounds can have significant effects onthe state of mind in the human brain [27,28]. For example, in awake and alert humans, several sound types including white noise, environmental sounds, and music have been shown to enhance arousal and improve task performance [29-33]. Furthermore, in the awakening of humans, Auditory Arousal Thresholds (AAT's) have been researched to understand the time it may take an individual to awaken in response to different alarm sounds . A recently published systematic review by McFarlane et al. (2020) reports on the current state of knowledge of auditory countermeasures for sleep inertia. A systematic review captures and reports on all relevant published work in peer-reviewed journals in a very formal way; and below we discuss for professionals and the general public the implications for work-related practices and future research based on current findings.