Optimal Being

Recent research has shed light on how different levels of illuminance—the measure of the amount of light—can enhance alertness and cognitive performance in humans. The study found that higher light levels affect specific areas of the brain region known as the hypothalamus, enhancing certain cognitive functions during tasks that involve executive and emotional processing. The findings were published in the journal   eLife . The primary motivation behind the study was to understand how varying intensities of light impact the human brain, particularly the hypothalamus, which plays a crucial role in regulating sleep, wakefulness, and cognitive functions. Light exposure is known to affect these areas in animal brains, but the specifics of these effects in humans remained unclear. Animal models have shown that certain brain regions respond to light in ways that affect behavior, but humans have different physiological and neurological complexities. For example, the human cortex matures la...

Participants who smelled odors while they slept performed better on word-recall tests. Smell is probably our most underappreciated sense. “If you ask people which sense they would be most willing to give up, it would be the olfactory system,” says Michael Leon, a neurobiologist at the University of California, Irvine. But a loss of smell has been linked to health complications such as  depression  and cognitive decline. And mounting evidence shows that olfactory training, which involves deliberately smelling strong scents on a regular basis, may help stave off that decline. Now a team of researchers led by Leon has successfully boosted cognitive performance by exposing people to smells while they sleep. Twenty participants—all older than 60 years and generally healthy—received six months of overnight olfactory enrichment, and all significantly improved their ability to recall lists of words compared with a control group. The study appeared in  Frontiers in Neuroscien...