Deep Sleep Brain Waves Offer Protection Against Alzheimer’s, Shows New Research

Credit: Ruliff Andrean for Unsplash+

Poor sleep quality has been linked to cognitive decline, neuro-degeneration and Alzheimer’s disease in seniors—but it may be possible to counteract certain risks.

A new study shows that specific sleep brain waves provide protection against the harmful effects of a brain chemical associated with wakefulness, sleep transition, and narcolepsy.

Concordia University-led researchers examined levels of the neurotransmitter orexin in the cerebral spinal fluid of 60 adults with mild to moderate Alzheimer’s Disease over a three-year period.

They found that individuals with elevated levels of orexin, which is vital to sleep and appetite regulation, were more likely to exhibit symptoms of cognitive decline, including poorer memory and thinking, more severe behavioral and psychiatric symptoms and had higher levels of biological markers associated with neurodegenerative disease and inflammation.

However, that relationship was found to be mitigated by specific brainwaves during sleep. Individuals who produced stronger sleep spindles and sleep oscillations — types of brainwaves associated with memory support and preservation — during non-rapid eye movement (NREM) sleep had less cognitive decline over time than those with weaker ones.

This sleep activity appears to provide neural resilience against the negative effects of higher levels of orexin on their cognition and mental health.

“This study shows that there is a direct association between orexin levels in the brain and biomarkers of Alzheimer’s disease,” says study co-author Thanh Dang-vu, a neurologist and professor in the Department of Health, Kinesiology and Applied Physiology.

Clear pathways to treatment

The study’s data, published in the journal Neurology, was collected by researchers at Lleida University in Catalonia, Spain. The 60 participants spent a night in a sleep laboratory where researchers recorded their brain activity using overnight poly-somnography. The following morning, cerebrospinal fluid samples were collected to measure orexin and other established Alzheimer’s biomarkers.

Participants also completed a series of cognitive and neuropsychiatric assessments at regular intervals over the next three years, allowing researchers to examine how sleep, brain chemistry and cognitive decline changed together over time.

“Having this longitudinal data is important, because Alzheimer’s disease is a moving target,” says the study’s co-first author Arsenio Paez, a neuroscience lecturer in the Sleep, Cognition and Neuroimaging Lab.

“With this data, we can see how the course of people’s Alzheimer’s disease changes over time. Alzheimer’s is a very long process, so this gives us a better picture of how conditions can change over time and we might intervene at different stages of the disorder.”

The researchers note that orexin-blocking drugs are already being used to treat insomnia and narcolepsy, and are being explored as possible therapies for Alzheimer’s disease.

This study suggests that monitoring sleep spindles, slow oscillations and orexin levels could help measure disease progression and to identify which patients would benefit from specialized treatment.“This study shows us that there are new ways to potentially act on sleep to slow the progression of Alzheimer’s disease, and opens the door for further studies moving forward,” says Dang-vu. Deep Sleep Brain Waves Offer Protection Against Alzheimer’s, Shows New Research

Read More........→September 04, 2026

70% Drop in Levels of Forever Chemicals Observed in Seabird Eggs Tracks Regulatory Success

Northern gannets on Bonaventure Island – credit, CC 3.0. BY-SA Bodoklecksel

Content of several “forever chemicals” in seabird eggs were found to have sharply decreased over the last 55 years by a team of scientists.

While first rising exponentially from during the 1960s, the chemicals, classed as PFAS, peaked in the 1990s before decreasing in line with regulatory oversight by North American governments.

PFAS are a class of chemicals that form water, stain, and heat-resistant coatings in multiple products which substantially contaminate environments around the world, and are linked to multiple detrimental health outcomes.

A study published in the journal Applied Toxicology that looked at PFAS concentrations in the eggs of northern gannets on Bonaventure Island found that the content of some of the most commonly used PFAS has fallen 70% and sometimes more.

These include perfluorooctanesulfonic acid (PFOS) and perfluorooctanoic acid (PFOA), which fell 74% and 40% respectively. Concentrations of perfluorohexanesulfonic acid, (PFHxS) another of these chemicals, was also 70% lower from baseline.

“We see this incredible rise to a peak where concentrations seem to be higher than toxicological threshold for those birds, then it really decreases in a nice way,” Raphael Lavoie, a co-author and ecotoxicologist with Environment and Climate Change Canada, told the Guardian. “The regulations are having a good effect.”

The seabird subjects and the long study period were notable strengths. The 55 years of data spans the rise in PFAS production, and the eventual decline as the environmental groups and regulators caught on to the toxicity in the late 90s and early 2000s.

Bonaventure Island is the world’s largest northern gannet breeding colony. These pescatarian birds are directly exposed to PFAS contamination due to the island’s position near the St. Lawrence Seaway, which, being connected to the Great Lakes manufacturing centers north and south of the border, was exposed to substantial amounts of PFAS during the 20th century.

The PFAS got into the fish which got into the gannets and then into their eggs. Tom Perkins for the Guardian wrote that in the late 90s, the chemical corporation M3 dramatically scaled back its production of commercial PFAS in the face of regulatory scrutiny. In 2015, the chemical sector struck an agreement with the EPA to phase out production of PFOA and PFOS, while 6 years earlier at the United Nations’ Stockholm Convention, several of the chemicals tested for in the study were subjected to elimination.

This included PFOA and PFHxS, while PFOS was restricted in everything but firefighting foam.

The study is a comprehensive demonstration of how these regulations are working to reduce the toxic load presented by PFAS in the environment. PFAS are referred to shorthanded as “forever chemicals,” however, and so the authors stress the need for continual environmental and regulatory vigilance, since any similar chemicals entering the environment today will remain, presumably forever. 70% Drop in Levels of Forever Chemicals Observed in Seabird Eggs Tracks Regulatory Success

Read More........→June 01, 2026