Mitochondria & Synapses - Consciousness & Working Memory - Dangerous Elk - Alzheimer's & Attention

[Breedlove, S]

https://www.thetransmitter.org/mitochondria/the-fast-expanding-repertoire-of-mitochondria-in-the-brain/

 The fast-expanding repertoire of mitochondria in the brain

By Giorgia Guglielmi

Neuroscience textbooks have long cast mitochondria as pure neuronal powerhouses: These bean-shaped organelles just crank out a cell’s energy. That picture, however, is starting to look incomplete. 

Mitochondria do far more than fuel neurons, a growing body of research suggests. They also appear to help synapses communicate, regulate neurotransmitter release and shape social behavior. Mitochondrial function has also been tied to autism and related neurodevelopmental conditions, though that link remains debated.

Even memory formation may lean on these tiny, double-membraned structures, according to a study published in Nature Metabolism in February. Increasing mitochondrial metabolism boosted long-term memory in both fruit flies and mice.

Mitochondria are “not just permissive but also instructive,” says Ezgi Hacisuleyman, assistant professor of molecular medicine at the Herbert Wertheim UF Scripps Institute for Biomedical Innovation & Technology, who was not involved in the February study. Her unpublished results show that mitochondrial proteins are translated near active synapses, for example.

Over the past decade, work from Hacisuleyman and others has fast expanded the repertoire of mitochondria in the brain. Taken together, she adds, the findings put mitochondria “more in the center of how we think about brain function and memory.” 

Mitochondria may be central to brain function, but they are not central inside neurons. Many synapses sit hundreds of micrometers away from a cell’s soma, so small, mobile mitochondria must travel there to deliver fuel in the form of ATP. In dendrites, mitochondria often linger near spines, and activity recruits them to presynaptic boutons, where they help stabilize neurotransmitter release.
© 2026 Simons Foundation

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https://www.scientificamerican.com/article/how-working-memory-could-give-rise-to-consciousness/

How working memory could give rise to consciousness

By Henry Taylor & The Conversation US

You know that feeling when you walk into a room and immediately forget why you came in? Maybe you were there to fetch your keys. On your way to the room, you were thinking about grabbing your keys. But once you arrive, your keys have completely disappeared from your mind.

This is sometimes known as the doorway effect, since it often strikes when you walk into a new room. Why does it happen? The answer has a lot to do with a faculty called working memory. Information gets stored in working memory when we need it for the tasks that we are engaged in right now (like remembering to grab your keys).

What makes working memory so intriguing is its close link to consciousness. The doorway effect suggests that when information is removed from working memory, it immediately seems to leave consciousness. It also suggests that it is easy for information in working memory to be forgotten.

The link between working memory and consciousness is getting increasing attention in psychology, philosophy and neuroscience. Could working memory somehow give rise to consciousness? In my new book, I explore the complex relationship between the two.
Working memory: both rich and poor

To understand the doorway effect, we’ll need to know a bit about working memory. One thing that makes working memory so special is that it’s so rich, both in terms of the information it has access to, and its processing power. According to recent models of working memory, it can draw information from sensory channels (vision, touch, smell etc), as well as from other memory systems such as long-term memory and also the brain’s system for processing language. In other words, working memory is where a lot of the information in your brain comes together.

Once working memory has that information, there’s a lot it can do with it. Inside working memory are a host of different smaller systems for specific tasks, including visual and spatial reasoning (like solving a Rubik’s cube) and storing chunks of information (like a phone number). There’s even a “central executive” system (my favorite). The executive is like a merciless boss, assigning tasks to the different systems within working memory and keeping everything under control.

© 2026 SCIENTIFIC AMERICAN
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https://www.sciencenews.org/article/aggressive-wildlife-encounters-elk-bear

The animal behind most aggressive wildlife encounters may surprise you

By Libby Riddle

A bear might seem like the scariest thing you could run into in a national park. But a new study suggests maybe you should be more worried about elk.  

Out of nearly 3,000 wildlife incidents in Canadian national parks, more than half involved an elk, researchers report July 2 in Frontiers in Conservation Science. But the risk of tangling with a given species also depended on what people were doing, say Holly Landles and conservation biologist Shashank Balakrishna of the University of York in England. 

Camping out? Be wary of elk grazing near your campsite. Quietly hiking or wildlife watching? Watch out for bears using the same trails.  

“By identifying situations where a potential conflict scenario is more likely, we can help visitors make informed decisions that improve safety whilst also reducing unnecessary disturbance to wildlife,” says Landles, who conducted this research as an undergraduate at York. 

Landles and Balakrishna analyzed 2,878 aggressive wildlife incidents from 2010 to 2023 involving five animals: black bears, grizzly bears, elk, coyotes and mule deer. Aggressive behaviors included chasing, attacking or bluffing a charge. The analysis identified which animal–human activity combinations were especially risky. 

Elk topped the list, involved in 62 percent of all the incidents. One of the riskiest combos was elk and camping — the animals turned up in 84 percent of campground incidents. This may be because Canada’s peak camping season aligns with when the animals mate and give birth — times of heightened aggression for the species.  

“Elk are herbivorous herd animals that don’t immediately inspire fear like a carnivore does,” Balakrishna says. Visitors may underestimate how aggressive they can be.   

© Society for Science & the Public 2000–2026. 
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https://nautil.us/memory-loss-may-not-be-the-earliest-sign-of-alzheimers-1282448

Memory Loss May Not Be the Earliest Sign of Alzheimer’s

By Jake Currie

Memory loss is by far the most notorious symptom of Alzheimer’s disease, but it might not be the initial sign of the illness. According to a new study published in Nature Communications, there’s an even earlier tell—impaired cognitive flexibility. 

Cognitive flexibility is one of the brain’s executive functions governing our ability to switch between different tasks, adapt to novel situations, learn new rules, and so on. To study changes in this vital function, neuroscientists at Texas A&M University used mice genetically engineered to produce the amyloid-beta plaques associated with Alzheimer’s disease (5xFAD mice). 

The team conditioned the mice to learn that a particular action (pulling a lever) led to a reward (a delicious food pellet). They then changed the rules to find out how they reacted. Healthy mice had no trouble adapting to the new regime, but the 5xFAD mice struggled, often repeatedly pulling the original lever without receiving a reward. 

Importantly, these cognitive flexibility problems surfaced earlier than the kinds of memory problems typically associated with Alzheimer’s. “We found that this function was impaired before we could detect deficits in spatial memory,” study author Jun Wang said in a statement. 

Taking a closer look into the 5xFAD mice brains, the researchers discovered abnormally high levels of neuroactivity in the medial prefrontal cortex, a region involved in decision-making and behavioral flexibility. Previous research has shown this kind of hyperactivity can lead to amyloid-beta plaques piling up, which in turn makes neurons even more excitable. It basically leads to a positive feedback loop.

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