A new study published in The Journal of the Acoustical Society of America examined how the different types of face masks affect the acoustics of speech. Lead by researcher Ryan Corey, an electrical and computer engineering postdoctoral researcher under professor Andrew Singer at the University of Illinois Urbana-Champaign, a team tested medical masks, disposable surgical masks, masks with clear plastic windows around the mouth, and homemade and store-bought cloth masks made of different fabric types and numbers of layers.
The study found that disposable surgical masks offer the best acoustic performance among all tested. Loosely woven 100 percent cotton masks also perform well but, as shown in a study by other Illinois researchers, they may not be as effective as surgical masks at blocking respiratory droplets.
That study showed that tightly woven cotton and blended fabrics may block more droplets, but Corey’s team found that they also block more sound. Based on the droplet study, Corey suggested that multilayer masks made of loosely woven cotton may offer a reasonable compromise between droplet-blocking efficiency and acoustic performance.
If you have a dog or cat, you’ve probably seen their ears moving toward an interesting or startling sound. For professional equestrians, watching the ears of their horse allows them to gauge their shifting attention. Humans still have these same muscles, and even more interesting is their relationship to our brain and how we pay attention. …
Tai Chi is not just for increasing balance; it may also help improve cognitive performance. In a recent randomized controlled trial, study participants who practiced a form of Tai Chi twice a week for six months improved their scores on the Montreal Cognitive Assessment (MoCA) when compared to a control group (Fuzhong et al, 2023)….
The majority of people are familiar with earthquakes, but there is another phenomenon that is not nearly as predictable, and louder—skyquakes. Skyquakes are enigmatic sounds, typically described as a very loud boom or trumpet-sounding noise that has no apparent cause and seems to come from the sky. Their sound is like distant, but very loud, thunder with…