Category: Neurology

Study Likely to Change Standard of Care for Deadly Vertebrobasilar Stroke

Ischaemic and haemorrhagic stroke. Credit: Scientific Animations CC4.0

Endovascular therapy (EVT), a minimally invasive surgery performed inside the blood vessels, is 2 ½ times more likely than standard medical management to achieve a positive outcome after vertebrobasilar stroke that affects the back of the brain, including the brain stem. A meta-analysis of four randomised clinical trials, published in The Lancet, was led by UPMC Stroke Institute director Raul Nogueira, MD.

Investigators from the US, Netherlands and China formed a multi-centre collaboration of all four randomised trials of EVT in vertebrobasilar occlusion with data that provides the strongest evidence to date of the benefits of EVT over alternative approaches for complicated vessel obstructions in life-sustaining areas of the brain.

Although vertebrobasilar artery occlusions interrupting blood flow in the back of the brain account for only a small fraction of all ischaemic strokes, they are especially deadly. Without an appropriate intervention, vertebrobasilar strokes lead to high rates of severe disability and mortality that may exceed 70%.

“While the overwhelming benefit of EVT for acute ischaemic strokes due to occlusions of large vessels that supply the anterior brain has been well established, the benefit of this therapy for vertebrobasilar artery occlusion, one of the most devastating forms of stroke, has been more controversial,” said Nogueira, endowed professor of neurology and neurosurgery at the University of Pittsburgh.

To address this uncertainty, the consortium of investigators, called VERITAS, focused on providing more precise, comprehensive and statistically powered estimates of the benefits of EVT with a particular focus on specific patient subgroups of clinical interest.

As the primary coordinating centre for the study, the Pitt team established common variables, definitions and trial specifications that laid the groundwork for a core pooled dataset from the four randomised controlled clinical trials ATTENTION, BAOCHE, BASICS and BEST of EVT for stroke due to vertebrobasilar artery occlusion.

Meta-analysis showed that at three months after the surgery, despite higher rates of brain bleeds with the procedure, EVT significantly reduced patient mortality and overall post-stroke disability, increasing patients’ functional independence. Notably, patients who underwent EVT were nearly 2 ½ times more likely to regain their ability to walk independently compared to patients who received the current medical standard of care, including intravenous thrombolytics.

“The results of the VERITAS collaboration are expected to influence treatment guidelines and impact stroke care globally,” Nogueira said. “We hope that this analysis sets the foundation for improved recovery after vertebrobasilar strokes and helps more people regain their independence after this catastrophic medical event.”

Source: University of Pittsburgh

Books Beat TV When it Comes to Brain Health

…but is that any surprise?

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It’s that time of the year when most of us get the chance to sit back and enjoy some well-deserved down time. But whether you reach for the TV controller, or a favourite book, your choice could have implications for your long-term brain health, say researchers at the University of South Australia who published their research in the Journals of Gerontology.

Assessing the 24-hour activity patterns of 397 older adults (aged 60+), researchers found that the context or type of activity that you engage in, matters when it comes to brain health. And specifically, that some sedentary (or sitting) behaviours are better for cognitive function than others.

When looking at different sedentary behaviours, they found that social or mentally stimulating activities such as reading, listening to music, praying, crafting, playing a musical instrument, or chatting with others are beneficial for memory and thinking abilities. Yet watching TV or playing video games are detrimental.

Researchers believe that there is likely a hierarchy of how sedentary behaviours relate to cognitive function, in that some have positive effects while others have negative effects.

It’s a valuable insight that could help reduce risks of cognitive impairment, particularly when at least 45% of dementia cases could be prevented through modifiable lifestyle factors.

In Australia, about 411,100 people (or one in every 1000 people) are living with dementia. Nearly two-thirds are women. Globally, the World Health Organization estimates that more than 55 million people have dementia with nearly 10 million new cases each year.

UniSA researcher Dr Maddison Mellow says that not all sedentary behaviours are equal when it comes to memory and thinking ability.

“In this research, we found that the context of an activity alters how it relates to cognitive function, with different activities providing varying levels of cognitive stimulation and social engagement,” Dr Mellow says.

“We already know that physical activity is a strong protector against dementia risk, and this should certainly be prioritised if you are trying to improve your brain health. But until now, we hadn’t directly explored whether we can benefit our brain health by swapping one sedentary behaviour for another.

“We found that sedentary behaviours which promote mental stimulation or social engagement — such as reading or talking with friends — are beneficial for cognitive function, whereas others like watching TV or gaming have a negative effect. So, the type of activity is important.

“And, while the ‘move more, sit less’ message certainly holds true for cardiometabolic and brain health, our research shows that a more nuanced approach is needed when it comes to thinking about the link between sedentary behaviours and cognitive function.”

Now, as the Christmas holidays roll around, what advice do researchers have for those who really want to indulge in a myriad of Christmas movies or a marathon of Modern Family?

“To achieve the best brain health and physical health benefits, you should prioritise movement that’s enjoyable and gets the heart rate up, as this has benefits for all aspects of health,” Dr Mellow says.

“But even small five-minute time swaps can have benefits. So, if you’re dead set on having a Christmas movie marathon, try to break up that time with some physical activity or a more cognitively engaged seated activity, like reading, at some point. That way you can slowly build up healthier habits.”

Source: University of South Australia

T Cells could Ease Brain Injury after Cardiac Arrest

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Despite improvements in CPR and ambulance response times, only about one in 10 people ultimately survive after out-of-hospital cardiac arrest (OHCA). Most patients hospitalised with OCHA die of brain injury, and no medications are currently available to prevent this outcome. A team led by researchers from Mass General Brigham found that immune cells may play a key role.

Using samples from patients who have had an OHCA, the team uncovered changes in immune cells just six hours after cardiac arrest that can predict brain recovery 30 days later. They pinpointed a particular population of cells that may provide protection against brain injury and a drug that can activate these cells, which they tested in preclinical models. Their results are published in Science Translational Medicine.

“Cardiac arrest outcomes are grim, but I am optimistic about jumping into this field of study because, theoretically, we can treat a patient at the moment injury happens,” said co-senior and corresponding author Edy Kim, MD, PhD, of the Division of Pulmonary and Critical Care Medicine at Brigham and Women’s Hospital. “Immunology is a super powerful way of providing treatment. Our understanding of immunology has revolutionised cancer treatment, and now we have the opportunity to apply the power of immunology to cardiac arrest.”

As a resident physician in the Brigham’s cardiac intensive care unit, Kim noticed that some cardiac arrest patients would have high levels of inflammation on their first night in the hospital and then rapidly improve. Other patients would continue to decline and eventually die. In order to understand why some patients survive and others do not, Kim and colleagues began to build a biobank – a repository of cryopreserved cells donated by patients with consent from their families just hours after their cardiac arrest.

The researchers used a technique known as single-cell transcriptomics to look at the activity of genes in every cell in these samples. They found that one cell population – known as diverse natural killer T (dNKT) cells – increased in patients who would have a favourable outcome and neurological recovery. The cells appeared to be playing a protective role in preventing brain injury.

To further test this, Kim and colleagues used a mouse model, treating mice after cardiac arrest with sulfatide lipid antigen, a drug that activates the protective NKT cells. They observed that the mice had improved neurological outcomes.

The researchers note that there are many limitations to mouse models, but making observations from human samples first could increase the likelihood of successfully translating their findings into intervention that can help patients. Further studies in preclinical models are needed, but their long-term goal is to continue to clinical trials in people to see if the same drug can offer protection against brain injury if given shortly after cardiac arrest.

“This represents a completely new approach, activating T cells to improve neurological outcomes after cardiac arrest,” said Kim. “And a fresh approach could lead to life-changing outcomes for patients.”

Source: Mass General Brigham

The Heart has a ‘Brain’ of its Own

Human heart. Credit: Scientific Animations CC4.0

New research from Karolinska Institutet and Columbia University shows that the heart has a mini-brain – its own nervous system that controls the heartbeat. A better understanding of this system, which is much more diverse and complex than previously thought, could lead to new treatments for heart diseases. The study, conducted on zebrafish, is published in Nature Communications.

The heart has long been thought to be controlled solely by the autonomic nervous system, which transmits signals from the brain. The heart’s neural network, which is embedded in the superficial layers of the heart wall, has been considered a simple structure that relays the signals from the brain. However, recent research suggests that it has a more advanced function than that.

Controlling the heartbeat

Scientists have now discovered that the heart has its own complex nervous system that is crucial to controlling its rhythm.

“This ‘little brain’ has a key role in maintaining and controlling the heartbeat, similar to how the brain regulates rhythmic functions such as locomotion and breathing,” explains Konstantinos Ampatzis, principal researcher and docent at the Department of Neuroscience, Karolinska Institutet, Sweden, who led the study.

The researchers identified several types of neurons in the heart that have different functions, including a small group of neurons with pacemaker properties. The finding challenges the current view on how the heartbeat is controlled, which may have clinical implications.

Surprising complexity revealed

“We were surprised to see how complex the nervous system within the heart is,” says Konstantinos Ampatzis. “Understanding this system better could lead to new insights into heart diseases and help develop new treatments for diseases such as arrhythmias.” 

The study was conducted on zebrafish, an animal model that exhibits strong similarities to human heart rate and overall cardiac function. The researchers were able to map out the composition, organisation and function of neurons within the heart using a combination of methods such as single-cell RNA sequencing, anatomical studies and electrophysiological techniques.

New therapeutic targets

“We will now continue to investigate how the heart’s brain interacts with the actual brain to regulate heart functions under different conditions such as exercise, stress, or disease,” says Konstantinos Ampatzis. “We aim to identify new therapeutic targets by examining how disruptions in the heart’s neuronal network contribute to different heart disorders.”

Source: Karolinska Institutet

Scientists Identify a Type of Brain Cell That is a Master Controller of Urination

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Researchers have identified a subset of brain cells in mice that act as the master regulators of urination.

The research, published as a Reviewed Preprint in eLife, is described by editors as an important study with convincing data showing that oestrogen receptor 1-expressing neurons (ESR1+) in the Barrington’s nucleus of the mouse brain coordinate both bladder contraction and relaxation of the external urethral sphincter.

Urination requires the coordinated function of two units of the lower urinary tract. The detrusor muscle of the bladder wall relaxes to allow the bladder to fill and empty, while the external sphincter opens when it’s appropriate to allow urine to flow out, but otherwise keeps tightly shut.

“Impairment of coordination between the bladder muscle and the sphincter leads to various urinary tract dysfunctions and can significantly degrade a person’s quality of life,” says first author Xing Li, Advanced Institute for Brain and Intelligence, School of Physical Science and Technology, Guangxi University, Nanning, China. “But although we know the individual nerve signalling pathways that control each of these urinary tract components, we don’t know which brain areas ensure they cooperate at the right time.”

To explore this, the authors used state-of-the-art live cell imaging to study the activity of brain cells in anaesthetised and awake mice during urination. They focused on a brain region called the pontine micturition centre (PMC), otherwise known as the Barrington’s nucleus, and compared the activity of different PMC nerve cell subtypes.

In their first experiments, they measured the activity of the cells as the bladder empties by measuring changes in levels of calcium. This revealed that the electrical firing rate of a subset of PMC cells expressing estrogen receptors (PMCESR1+ cells) was tightly linked to bladder emptying. When they combined this with monitoring bladder physiology, they found that it was not only the timing of PMCESR1+ cell activity that correlated with bladder emptying, but the strength of cell electrical activity, too.

Next, they tested what happened to urination if they blocked or triggered the PMCESR1+ cells. They found that when PMCESR1+ cell activity was blocked, the amount of urine the mice passed was significantly reduced and ongoing urination was suspended from the moment the cells were inactive. To understand the mechanism behind this, they measured the activity of the bladder muscle and sphincter. They discovered that both increase of bladder pressure and sphincter muscle bursting activity associated with bladder emptying both stopped when PMCESR1+ cell activity was blocked during an ongoing voiding even. Similarly, when PMCESR1+ cells were artificially activated using light, bladder emptying occurred 100% of the time. This suggests that PMCESR1+ cells work as a reliable master switch that either initiates or suspends bladder emptying.

To test whether PMCESR1+ cells can influence bladder emptying independently of controlling the sphincter, they disconnected either the nerve carrying messages from the brain to the sphincter, or the nerve carrying messages from the brain to the bladder. They found that PMCESR1+ cell control of the bladder was fully operational even when communication to the sphincter was blocked, and vice versa. This showed the cells could control the bladder and sphincter independently of one another, but the question remained: could they coordinate the action of the bladder muscle and sphincter together? That is, operate them in a controlled, perfectly timed manner, to trigger bladder emptying when appropriate?

To explore this, they simultaneously recorded bladder pressure and electromyography measurements of sphincter activity. The timing of bladder pressure changes immediately before sphincter bursting activity was consistent for both spontaneous bladder emptying and emptying caused by activating the PMCESR1+ cells, showing that these cells can coordinate the two steps in a precisely temporal sequence and controlled way.

“Our study shows that a subset of cells in the Barrington’s nucleus of the brain can initiate and suspend bladder emptying with 100% accuracy when needed, for example, to release only a small volume for landmarking by animals, or for a human to urinate into a small sample tube for a health check,” concludes senior author Xiaowei Chen, Third Military Medical University, and Chongqing Institute for Brain and Intelligence, China. “While other cells will no doubt be involved in perfect urination control, our pinpointing of PMCESR1+ cells’ crucial role in bladder–sphincter coordination will aid the development of targeted therapies for treating urination dysfunction caused by brain or spinal cord injury or peripheral nerve damage.”

Source: eLife

Soccer Headers may be More Damaging to Brain than Thought

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Soccer heading may cause more damage to the brain than previously thought, according to a study presented at the annual meeting of the Radiological Society of North America (RSNA).

Heading is a widely used technique in soccer where the players control the direction of the ball by hitting it with their head. In recent years, research has been done that suggests a link between repeated head impacts and neurodegenerative diseases, such as chronic traumatic encephalopathy (CTE).

“The potential effects of repeated head impacts in sport are much more extensive than previously known and affect locations similar to where we’ve seen CTE pathology,” said study senior author Michael L. Lipton, MD, PhD, professor of radiology at Columbia University Irving Medical Center. “This raises concern for delayed adverse effects of head impacts.”

While prior studies have identified injuries to the brain’s white matter in soccer players, Dr Lipton and colleagues used a new approach in diffusion MRI to analyse microstructure close to the surface of the brain.

To identify how repeated head impacts affect the brain, the researchers compared brain MRIs of 352 male and female amateur soccer players, ranging in age from 18 to 53, to brain MRIs of 77 non-collision sport athletes, such as runners.

Soccer players who headed the ball at high levels showed abnormality of the brain’s white matter adjacent to sulci, which are deep grooves in the brain’s surface. Abnormalities in this region of the brain are known to occur in very severe traumatic brain injuries.

The abnormalities were most prominent in the frontal lobe of the brain, an area most susceptible to damage from trauma and frequently impacted during soccer heading. More repetitive head impacts were also associated with poorer verbal learning.

“Our analysis showed that the white matter abnormalities represent a mechanism by which heading leads to worse cognitive performance,” Dr Lipton said.

Most of the participants of the study had never sustained a concussion or been diagnosed with a traumatic brain injury. This suggests that repeated head impacts that don’t result in serious injury may still adversely affect the brain.

“The study identifies structural brain abnormalities from repeated head impacts among healthy athletes,” Dr Lipton said. “The abnormalities occur in the locations most characteristic of CTE, are associated with worse ability to learn a cognitive task and could affect function in the future.”

The results of this study are also relevant to head injuries from other contact sports. The researchers stress the importance of knowing the risks of repeated head impacts and their potential to harm brain health over time.

“Characterising the potential risks of repetitive head impacts can facilitate safer sport engagement to maximise benefits while minimising potential harms,” Dr Lipton said. “The next phase of the study is ongoing and examines the brain mechanisms underlying the MRI effects and potential protective factors.”

Source: Radiological Society of North America

Concussions from American Football Slow Brain Activity of High Schoolers

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A new study of high school American football players found that concussions affect an often-overlooked but important brain signal. The findings are presented at the annual meeting of the Radiological Society of North America (RSNA).

Reports have emerged in recent years warning about the potential harms of youth contact sports on developing brains. Contact sports, including high school football, carry a risk of concussion. Symptoms of concussion commonly include cognitive disturbances, such as difficulty with balancing, memory or concentration.

Many concussion studies focus on periodic brain signals. These signals appear in rhythmic patterns and contribute to brain functions such as attention, movement or sensory processing. Not much is known about how concussions affect other aspects of brain function, specifically, brain signals that are not rhythmic.

“Most previous neuroscience research has focused on rhythmic brain signaling, which is also called periodic neurophysiology,” said study lead author Kevin C. Yu, BS, a neuroscience student at Wake Forest University School of Medicine. “On the other hand, aperiodic neurophysiology refers to brain signals that are not rhythmic.”

Aperiodic activity is typically treated as ‘background noise’ on brain scans, but recent studies have shown that this background noise may play a key role in how the brain functions.

“While it’s often overlooked, aperiodic activity is important because it reflects brain cortical excitability,” said study senior author Christopher T. Whitlow, MD, PhD, MHA, radiology professor at Wake Forest University School of Medicine.

Cortical excitability is a vital part of brain function. It reflects how nerve cells, or neurons, in the brain’s cortex respond to stimulation and plays a key role in cognitive functions like learning and memory, information processing, decision making, motor control, wakefulness and sleep.

To gain a better understanding of brain rhythms and trauma, the researchers sought to identify the impacts of concussions on aperiodic activity.

Pre- and post-season resting-state magnetoencephalography (MEG) data was collected from 91 high school football players, of whom 10 were diagnosed with a concussion. MEG is a neuroimaging technique that measures the magnetic fields that the brain’s electrical currents produce.

A clinical evaluation tool for concussions called the Post-Concussive Symptom Inventory was correlated with pre- and post-season physical, cognitive and behavioral symptoms.

High school football players who sustained concussions displayed slowed aperiodic activity. Aperiodic slowing was strongly associated with worse post-concussion cognitive symptoms and test scores.

Slowed aperiodic activity was present in areas of the brain that contain chemicals linked with concussion symptoms like impaired concentration and memory.

“This study is important because it provides insight into both the mechanisms and the clinical implications of concussion in the maturing adolescent brain,” said co-lead author Alex I. Wiesman, PhD, assistant professor at Simon Fraser University. “Reduced excitability is conceptually a very different brain activity change than altered rhythms and means that a clear next step for this work is to see whether these changes are related to effects of concussion on the brain’s chemistry.”

The findings from the study may also influence tracking of post-concussion symptoms and aid in finding new treatments to improve recovery.

“Our study opens the door to new ways of understanding and diagnosing concussions, using this novel type of brain activity that is associated with concussion symptoms,” Dr Whitlow said. “It highlights the importance of monitoring kids carefully after any head injury and taking concussions seriously.”

Source: Radiological Society of North America

New Insights into Sleep Uncover Mechanism for Enhancing Cognitive Function

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While it’s well known that sleep enhances cognitive performance, the underlying neural mechanisms, particularly those related to nonrapid eye movement (NREM) sleep, remain largely unexplored. A new study by a team of researchers coordinated by Rice University’s Valentin Dragoi, has nonetheless uncovered a key mechanism by which sleep enhances neuronal and behavioural performance, potentially changing our fundamental understanding of how sleep boosts brainpower.

The research, published in Science, reveals how NREM sleep – such as in a nap – fosters brain synchronisation and enhances information encoding, shedding new light on this sleep stage. The researchers replicated these effects through invasive stimulation, suggesting promising possibilities for future neuromodulation therapies in humans. The implications of this discovery potentially pave the way for innovative treatments for sleep disorders and even methods to enhance cognitive and behavioural performance.

The investigation involved an examination of the neural activity in multiple brain areas in macaques while the animals performed a visual discrimination task before and after a 30-minute period of NREM sleep. Using multielectrode arrays, the researchers recorded the activity of thousands of neurons across three brain areas: the primary and midlevel visual cortices and the dorsolateral prefrontal cortex, which are associated with visual processing and executive functions. To confirm that the macaques were in NREM sleep, researchers used polysomnography to monitor their brain and muscle activity alongside video analysis to ensure their eyes were closed and their bodies relaxed.

The findings demonstrated that sleep improved the animals’ performance in the visual task with enhanced accuracy in distinguishing rotated images. Meanwhile, the macaques that experienced quiet wakefulness without falling asleep did not show the same performance boost.

“During sleep, we observed an increase in low-frequency delta wave activity and synchronised firing among neurons across different cortical regions,” said first author Dr Natasha Kharas. “After sleep, however, neuronal activity became more desynchronised compared to before sleep, allowing neurons to fire more independently. This shift led to improved accuracy in information processing and performance in the visual tasks.”

The researchers also simulated the neural effects of sleep through low-frequency electrical stimulation of the visual cortex. They applied a 4-Hz stimulation to mimic the delta frequency observed during NREM sleep while the animals were awake. This artificial stimulation reproduced the desynchronization effect seen after sleep and similarly enhanced the animals’ task performance, suggesting that specific patterns of electrical stimulation could potentially be used to emulate the cognitive benefits of sleep.

“This finding is significant because it suggests that some of the restorative and performance-enhancing effects of sleep might be achieved without the need for actual sleep,” said Dragoi, study co-author, professor of electrical and computer engineering at Rice and professor of neuroscience at Weill Cornell. “The ability to reproduce sleeplike neural desynchronisation in an awake state opens new possibilities for enhancing cognitive and perceptual performance in situations where sleep is not feasible – such as for individuals with sleep disorders or in extenuating circumstances such as space exploration.”

The researchers further investigated their findings by building a large neural network model. They found that during sleep, both excitatory and inhibitory connections in the brain become weaker, but they do so asymmetrically, making inhibitory connections weaker than excitatory connections, which causes an increase in excitation.

“We have uncovered a surprising solution that the brain employs after sleep whereby neural populations participating in the task reduce their level of synchrony after sleep despite receiving synchronizing inputs during sleep itself,” Dragoi said.

The idea that NREM sleep effectively “boosts” the brain in this way, and that this resetting can be mimicked artificially, offers potential for developing therapeutic brain stimulation techniques to improve cognitive function and memory.

“Our study not only deepens our mechanistic understanding of sleep’s role in cognitive function but also breaks new ground by showing that specific patterns of brain stimulation could substitute for some benefits of sleep, pointing toward a future where we might boost brain function independently of sleep itself,” Dragoi said.

Source: Rice University

Cannabis Disrupts Brain Activity in Young Adults Prone to Psychosis

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Young adults at risk of psychosis show reduced brain connectivity, a deficit that cannabis use appears to worsen, a new study has found. The breakthrough paves the way for psychosis treatments targeting symptoms that current medications miss. In the first-of-its-kind study, McGill University researchers detected a marked decrease in synaptic density in individuals at risk of psychosis, compared to a healthy control group.

“Not every cannabis user will develop psychosis, but for some, the risks are high. Our research helps clarify why,” said Dr Romina Mizrahi, senior author of the study and professor in McGill’s Department of Psychiatry.

“Cannabis appears to disrupt the brain’s natural process of refining and pruning synapses, which is essential for healthy brain development.”

Hope for new treatments

Using advanced brain scanning technology, the team studied 49 participants aged 16 to 30, including individuals with recent psychotic symptoms and those considered at high risk. The results, published in JAMA Psychiatry, indicate that lower synaptic density is linked to social withdrawal and lack of motivation, symptoms the researchers say are difficult to treat.

“Current medications largely target hallucinations, but they don’t address symptoms that make it difficult to manage social relationships, work, or school,” said first author Belen Blasco, a PhD student at McGill’s Integrated Program in Neuroscience. “By focusing on synaptic density, we may eventually develop therapies that enhance social function and quality of life for those affected.”

While cannabis is a known risk factor for developing psychosis, which can progress to schizophrenia, this is the first time researchers have measured structural changes in the brains of a high-risk population in real time.

The team’s next research phase will explore whether these observed brain changes could predict psychosis development, potentially enabling earlier intervention.

Source: McGill University

Workouts – or Disturbed Sleep – Impact Brain Activity Weeks Later

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In a rare, longitudinal study, researchers from Aalto University and the University of Oulu tracked one person’s brain and behavioural activity for five months using brain scans and data from wearable devices and smartphones. The results appear in PLOS Biology.

“We wanted to go beyond isolated events,” says research leader (and study participant) Ana Triana. “Our behaviour and mental states are constantly shaped by our environment and experiences. Yet, we know little about the response of brain functional connectivity to environmental, physiological, and behavioural changes on different timescales, from days to months.”

The study found that the brain does not respond to daily life in immediate, isolated bursts. Instead, brain activity evolves in response to sleep patterns, physical activity, mood, and respiration rate over many days. This suggests that even a workout or a restless night from last week could still affect the brain – and therefore attention, cognition and memory – well into next week.

The research also revealed a strong link between heart rate variability – a measure of the heart’s adaptability – and brain connectivity, particularly during rest. This suggests that impacts on the body’s relaxation response, like stress management techniques, could shape brain wiring even when not actively concentrating on a task. Physical activity was also found to positively influence the way brain regions interact, potentially impacting memory and cognitive flexibility. Even subtle shifts in mood and heart rate left lasting imprints for up to 15 days.

Study goes beyond a snapshot

The research is unusual in that few brain studies involve detailed monitoring over days and weeks. “The use of wearable technology was crucial,” says Triana. “Brain scans are useful tools, but a snapshot of someone lying still for half an hour can only show so much. Our brains do not work in isolation.”

Triana was herself the subject of the research, monitored as she went about her daily life. Her unique role as both lead author and study participant added complexity, but also brought firsthand insights into how best to maintain research integrity over several months of personalised data collection.  Data from the devices and twice-weekly brain scans were complemented by qualitative data from mood surveys. 

The researchers identified two distinct response patterns: a short-term wave lasting under seven days and a long-term wave up to 15 days. The former reflects rapid adaptations, like how focus is impacted by poor sleep, but it recovers quickly. The long wave suggests more gradual, lasting effects, particularly in areas tied to attention and memory. 

Single-subject studies offer opportunities for improving mental health care 

The researchers hope their innovative approach will inspire future studies that combine brain data with everyday life to help personalise mental health treatment. 

“We must bring data from daily life into the lab to see the full picture of how our habits shape the brain, but surveys can be tiring and inaccurate,” says study co-author, neuroscientist and physician Dr Nick Hayward. “Combining concurrent physiology with repeated brain scans in one person is crucial. Our approach gives context to neuroscience and delivers very fine detail to our understanding of the brain.”

The study is also a proof-of-concept for patient research. Tracking brain changes in real time could help detect neurological disorders early, especially mental health conditions where subtle signs might be missed.

“Linking brain activity with physiological and environmental data could revolutionise personalised healthcare, opening doors for earlier interventions and better outcomes,” says Triana.

Source: Aalto University