Lifeboat Foundation: Safeguarding Humanity
Toggle light / dark theme

Blog

Category: neuroscience – Page 17

Sleep-like Slow Waves During Wakefulness Mediate Attention and Vigilance Difficulties in Adult Attention-Deficit/Hyperactivity Disorder

New in JNeurosci from Pinggal et al: Medication-withdrawn adults with ADHD exhibit more sleep-like brain activity while awake than neurotypical adults that is linked to poorer performance in a task that requires sustained attention.

▶️

Attention-Deficit/Hyperactivity Disorder (ADHD) is characterised by behavioural variability and heightened inattention associated with increased mind wandering (MW) and mind blanking (MB). Individuals with ADHD frequently experience sleep disorders and excessive daytime sleepiness, suggesting interactions between attention and arousal systems. Research examining brain activity using electroencephalography (EEG) has demonstrated that sleep-like slow waves (SW) during wakefulness are linked to inattention in neurotypical individuals following sleep deprivation, yet their role in ADHD remains unclear. This study investigated whether individuals with ADHD present with altered waking SW distribution compared to neurotypical controls and whether SW explain attentional difficulties in ADHD.

Adults with (n = 32) and without ADHD (n = 31) completed a sustained attention task while EEG recorded brain activity. Mental state probes (on-task, MW, MB) were embedded within the task. Sleep-like SW reflect cortical slowing and were detected from EEG activity. Omission/commission errors, reaction time (RT), RT variability, mental state reports and subjective sleepiness were analysed. Mediation analysis examined whether SW density explained ADHD-related performance differences.

Individuals with ADHD exhibited more commission errors, MW and MB, more theta oscillations over fronto-temporal electrodes and higher SW density (SW/min) over parieto-temporal electrodes. Increased SW density correlated with higher omission errors, slower RTs, greater RT variability, and elevated sleepiness ratings. On-task reports were negatively correlated with SW density. Mediation analysis revealed that SW density significantly accounted for ADHD-related attentional difficulties.

Exercise triggers memory-related brain ‘ripples’ in humans

The team recruited 14 patients between 17 and 50 years of age, to participate. After a brief warmup, participants rode a stationary bike for 20 minutes at a pace they could maintain for the duration. Researchers recorded the participants’ brain activity before and after the cycling session using intracranial electroencephalography (iEEG), which utilizes implanted electrodes to measure neural activity in the brain. The recordings showed an increased rate of ripples originating in the hippocampus and connecting with cortical regions of the brain known to be involved in learning and memory performance.

“We’ve known for years that physical exercise is often good for cognitive functions like memory, and this benefit is associated with changes in brain health, largely from behavioral studies and noninvasive brain imaging,” says the study’s corresponding author. “By directly recording brain activity, our study shows, for the first time in humans, that even a single bout of exercise can rapidly alter the neural rhythms and brain networks involved in memory and cognitive function.”

The author says the results apply beyond the epileptic patients who participated. ScienceMission sciencenewshighlights.

A single session of physical exercise can spawn a boost of neural activity in brain networks that underlie learning and memory, according to a new study.

The researchers measured neural activity in the brains of patients with epilepsy before and after they completed a bout of physical exercise. The results showed that a single exercise session produced in the participants a burst of high-frequency brain waves, called ripples, emanating from the hippocampus to areas of the brain involved in learning and recall.

Neuroscientists have documented ripples relevant to memory in mice and rats, but they had not confirmed the link in humans, mainly because electrodes need to be implanted in the brain to obtain recordings. Instead, researchers had theorized the ripples’ role in humans, based on studies in people that measured changes in oxygenated blood in the brain after exercise. This new study marks the first time researchers have been able to see the neurons in action in people following exercise, the authors report.

Continue reading “Exercise triggers memory-related brain ‘ripples’ in humans” | >

Are Faster-Than-Light Messages Already Reaching Us?

What if the universe is already sending messages faster than light… and humanity has been too primitive to recognize them?

In this episode of Divergent Files, we investigate one of the most disturbing possibilities in modern physics: that information may already be moving beyond the speed limit we were taught could never be broken.

Quantum entanglement. Nonlocality. Unexplained cosmic bursts. Declassified research into remote viewing, anomalous cognition, and consciousness. Different fields. Different languages. Same uncomfortable pattern.

Something may be traveling farther, faster, and stranger than our current models can fully explain.

This is not a claim of proof.

It’s a grounded investigation into the science, the anomalies, and the classified edges of research that all point toward the same question:

Continue reading “Are Faster-Than-Light Messages Already Reaching Us?” | >

Three anesthesia drugs all have the same effect in the brain, MIT researchers find

When patients undergo general anesthesia, doctors can choose among several drugs. Although each of these drugs acts on neurons in different ways, they all lead to the same result: a disruption of the brain’s balance between stability and excitability, according to a new MIT study.

This disruption causes neural activity to become increasingly unstable, until the brain loses consciousness, the researchers found. The discovery of this common mechanism could make it easier to develop new technologies for monitoring patients while they are undergoing anesthesia.

“What’s exciting about that is the possibility of a universal anesthesia-delivery system that can measure this one signal and tell how unconscious you are, regardless of which drugs they’re using in the operating room,” says Earl Miller, the Picower Professor of Neuroscience and a member of MIT’s Picower Institute for Learning and Memory.

Miller, Edward Hood Taplin Professor of Medical Engineering and Computational Neuroscience Emery Brown, and their colleagues are now working on an automated control system for delivery of anesthesia drugs, which would measure the brain’s stability using EEG and then automatically adjust the drug dose. This could help doctors ensure that patients stay unconscious throughout surgery without becoming too deeply unconscious, which can have negative side effects following the procedure.

Miller and Ila Fiete, a professor of brain and cognitive sciences, the director of the K. Lisa Yang Integrative Computational Neuroscience Center (ICoN), and a member of MIT’s McGovern Institute for Brain Research, are the senior authors of the new study, which appears today in Cell Reports. MIT graduate student Adam Eisen is the paper’s lead author.

Excellent work Earl Miller and team!

Read More

Continue reading “Three anesthesia drugs all have the same effect in the brain, MIT researchers find” | >

Consciousness is the hidden architecture behind fundamental and quantum physics

Physics and phenomenology are usually taken to inhabit different worlds. Physics aims at a description of objective reality in mathematical terms. Phenomenology—the philosophical movement inaugurated by Edmund Husserl—is an a priori investigation into consciousness and into the ways things appear in experience. Physics deals with equations, invariants, and symmetries, aiming to represent reality minus observers; phenomenology seems to concern precisely what physics leaves out: subjectivity, consciousness, meaning. If the two meet at all, it is only in polite, but ultimately inconsequential, interdisciplinary dialogue.

My claim is that this picture is mistaken. Physics does not stand outside phenomenology. It presupposes the very structures phenomenology seeks to analyse—above all, the structured correlation between subject and object through which objectivity first becomes intelligible. The task, therefore, is not to unite two distant domains, but to recognize a relation that has been there from the beginning.

To make this more tangible, consider what physics means by objectivity. Contrary to the image sometimes promoted in popular science—objectivity as detachment from all observers—in spacetime physics, objectivity is defined by invariance across observers. A physical description is deemed objective if it holds regardless of the coordinate frame in which it is expressed.

Differences in brain activity between ADHD and neurotypical adults

Elaine Pinggal from Monash University, and colleagues assessed how sleep-like brain activity in awake adults influences sustained attention during a task.

The researchers compared sleep-like brain activity from 32 medication-withdrawn adults with ADHD to 31 neurotypical adults as participants performed a task requiring sustained attention. The findings have been published in JNeurosci.

The ADHD group had more sleep-like brain activity, which was associated with more lapses in attention. Further analyses revealed that this activity may drive the relationship between ADHD and attention problems, including task errors, slower reaction times, and sleepiness.

The Brain’s Learning Algorithm Isn’t Backpropagation

To try everything Brilliant has to offer—free—for a full 30 days, visit https://brilliant.org/ArtemKirsanov. You’ll also get 20% off an annual premium subscription.

=====
My name is Artem, I’m a neuroscience PhD student at Harvard University.
🌎 Website and Social links: https://kirsanov.ai/
📥 \

Read more

Early adult drinking linked to middle-age cognitive decline—even after extended abstinence

It’s well known that alcohol consumption is an age-old method for coping with stress. But recent research led by the University of Massachusetts Amherst has found that when such self-medication begins in early adulthood, negative cognitive effects start to show up in middle age—even after long periods of total abstinence. The study is published in the journal Alcohol, Clinical and Experimental Research.

These negative effects include a decreased ability to cope with changing situations, an increased likelihood to drink when stressed, and the kinds of cognitive decline associated with dementia and Alzheimer’s disease. The new research helps us understand how alcohol rewires the brain’s circuitry and can help suggest new approaches for helping people adapt to the long-term effects of alcohol use.

Researchers have long known that stress and alcohol have a mutually reinforcing relationship: Alcohol can help take the edge off stressful situations, but in so doing it can decrease the brain’s ability to manage stress on its own, meaning one has to keep drinking, and drinking more, in order to relieve stress from a bad day. At the same time, the more one drinks, the more stress can accrue from increasingly poor decision-making. It can be a vicious cycle that gets harder to break the more the brain’s circuitry changes. But what about the long-term effects of stress and alcohol?

/* */