Posts tagged brain activity
Articles and news from the latest research reports.
Could poor sleep contribute to symptoms of schizophrenia?
Neuroscientists studying the link between poor sleep and schizophrenia have found that irregular sleep patterns and desynchronised brain activity during sleep could trigger some of the disease’s symptoms. The findings, published in the journal Neuron, suggest that these prolonged disturbances might be a cause and not just a consequence of the disorder’s debilitating effects.
The possible link between poor sleep and schizophrenia prompted the research team, led by scientists from the University of Bristol, the Lilly Centre for Cognitive Neuroscience and funded by the Medical Research Council (MRC), to explore the impact of irregular sleep patterns on the brain by recording electrical brain activity in multiple brain regions during sleep.
For many people, sleep deprivation can affect mood, concentration and stress levels. In extreme cases, prolonged sleep deprivation can induce hallucinations, memory loss and confusion all of which are also symptoms associated with schizophrenia.
Dr Ullrich Bartsch, one of the study’s researchers, said: “Sleep disturbances are well-documented in the disease, though often regarded as side effects and poorly understood in terms of their potential to actually trigger its symptoms.”
Using a rat model of the disease, the team’s recordings showed desynchronisation of the waves of activity which normally travel from the front to the back of the brain during deep sleep. In particular the information flow between the hippocampus — involved in memory formation, and the frontal cortex — involved in decision-making, appeared to be disrupted. The team’s findings reported distinct irregular sleep patterns very similar to those observed in schizophrenia patients.
Dr Matt Jones, the lead researcher from the University’s School of Physiology and Pharmacology, added: “Decoupling of brain regions involved in memory formation and decision-making during wakefulness are already implicated in schizophrenia, but decoupling during sleep provides a new mechanistic explanation for the cognitive deficits observed in both the animal model and patients: sleep disturbances might be a cause, not just a consequence of schizophrenia. In fact, abnormal sleep patterns may trigger abnormal brain activity in a range of conditions.”
Cognitive deficits — reduced short term memory and attention span, are typically resistant to medication in patients. The findings from this study provide new angles for neurocognitive therapy in schizophrenia and related psychiatric diseases.
(Source: eurekalert.org)
Watch A French Researcher Control A Robot With His Brain
Researchers in Japan are using a brain-machine interface to control the actions of a humanoid robot. The goal is to allow people “to feel embodied in the body of a humanoid robot,” in the words of one researcher.
Roboticists at the CRNS-AIST Joint Robotics Laboratory, a collaboration between the French National Center for Scientific Research and the Japanese Institute of Advanced Industrial Science and Technology, are trying to interpret brain waves into actions that can be understood by a robot. In the video, a volunteer wears an electrode cap and watches a screen with flashing dots, which is used to teach his brain to associate flickering objects with actions. By focusing his attention, he can induce actions, which are translated from his brain activity into robotic motion.
A signal processing unit on a computer translates his brain activity and classifies it into a series of tasks. Then the team can instruct the robot on which task to perform. It could help paraplegics who can’t perform certain tasks on their own. Or it could be used for crazyfuture tourism, says Abderrahmane Kheddar, director of the JRL: “A paraplegic patient in Rome would be able to pilot a humanoid robot for sightseeing in Japan.”
Alzheimer gene may boost young brains but contributes to ‘burnout’ in later years
A gene that confers a higher risk for dementia in old age could also promote better-than-average memory and verbal skills in youth, according to a new University of Sussex-led study.
Neuroscientists tested the cognitive abilities of those with a particular gene variant, known as ‘APOE e4’, found in approximately 25 per cent of the population, against those without it. They also looked at the brain structure and brain activities of both groups during the tasks.
They found that young people with the e4 variant performed better in attention tests (one involving episodic memory of words, the other requiring participants to spot number sequences), which correlated with increased task-related brain activation as detected by MRI scans. The researchers also noticed subtle differences in the white matter of the brains of those with the variant.
Lead researcher Professor Jennifer Rusted said: “Earlier studies suggested that those with the e4 variant outperform those without it in tasks such as memory, speed of processing, mental arithmetic and verbal fluency.
But it is also well-established that this gene is a risk factor for Alzheimer’s disease. The suggestion is that while this confers cognitive advantages in early life, leading to higher achievement, it may also increase susceptibility to memory failure as we enter old age.
“Our study is the first to show that subtle differences in the structure and activation of the brain during cognitive tasks in APOE e4 carriers are linked to their cognitive performance. It is possible that the brain over-activations that we see in youth have negative effects over the longer term and contribute to a kind of ‘burnout’ in older adulthood.”
‘APOE e4 polymorphism in young adults is associated with improved attention andindexed by distinct neural signatures’, by Professor Jennifer Rusted, Dr Simon Evans and Dr Sarah King in the School of Psychology, Dr Nick Dowell and Professor Paul Tofts in the Clinical Imaging Sciences Centre at the Brighton and Sussex Medical School (BSMS), and Dr Najo Tabet in the BSMS Institute of Postgraduate Medicine, is published in NeuroImage.
(Source: sussex.ac.uk)
Seeing someone yawn or hearing someone laugh makes you likely to follow suit. The same goes for scratching an itch. Now, for the first time, researchers have investigated the neural basis of contagious itch, identifying several brain regions whose activity predicts how susceptible people are to feeling itchy when they see someone else scratch.
Researchers in the United Kingdom showed volunteers video clips of people scratching an arm or a spot on their chest. Sure enough, subjects reported feeling more itchy, and most scratched themselves at least once during the experiment. When a subset of the volunteers watched the videos inside an functional magnetic resonance imaging scanner, the scans revealed activity in several of the same brain regions known to fire up in response to an itch-inducing histamine injection.
Activity in three of these areas correlated with subjects’ self-reported itchiness, the team reports online in the Proceedings of the National Academy of Sciences. Personality tests suggest that the trait that best predicts susceptibility to contagious itch is neuroticism, not empathy, as some researchers have suggested.
Early stress may sensitize girls’ brains for later anxiety
High levels of family stress in infancy are linked to differences in everyday brain function and anxiety in teenage girls, according to new results of a long-running population study by University of Wisconsin-Madison scientists.
The study highlights evidence for a developmental pathway through which early life stress may drive these changes. Here, babies who lived in homes with stressed mothers were more likely to grow into preschoolers with higher levels of cortisol, a stress hormone. In addition, these girls with higher cortisol also showed less communication between brain areas associated with emotion regulation 14 years later. Last, both high cortisol and differences in brain activity predicted higher levels of adolescent anxiety at age 18.
The young men in the study did not show any of these patterns.
"We wanted to understand how stress early in life impacts patterns of brain development which might lead to anxiety and depression,” says first author Dr. Cory Burghy of the Waisman Laboratory for Brain Imaging and Behavior. "Young girls who, as preschoolers, had heightened cortisol levels, go on to show lower brain connectivity in important neural pathways for emotion regulation — and that predicts symptoms of anxiety during adolescence."
To test this, scans designed by Dr. Rasmus Birn, assistant professor of psychiatry in the UW School of Medicine and Public Health, showed that teenage girls whose mothers reported high levels of family stress when the girls were babies show reduced connections between the amygdala or threat center of the brain and the ventromedial prefrontal cortex, a part of the brain responsible for emotional regulation. Birn used a method called resting-state functional connectivity (fcMRI), which looks at the brain connections while the brain is at a resting state.
The study was published in Nature Neuroscience.
Mickey Hart, Grateful Dead percussionist, and neurologist Adam Gazzaley, M.D., Ph.D., professor at the University of California San Francisco made history by becoming the first to sonify and visualize brain activity in real time in front of a live audience. The two did so at the closing session of Life @50+, the AARP National Event & Expo in New Orleans on September 22nd.
Making Memories: Drexel Researchers Explore the Anatomy of Recollection
What was your high school mascot? Where did you put your keys last night? Who was the first president of the United States?
Groups of neurons in your brain are currently sending electromagnetic rhythms through established pathways in order for you to recall the answers to each of these questions. Researchers in Drexel’s School of Biomedical Engineering, Science and Health Systems are now getting a rare look inside the brain to discover the exact pattern of activity that produces a memory.
Dr. Joshua Jacobs, a professor in Drexel’s School of Biomedical Engineering, Science and Health Systems, is analyzing data accumulated from 60 epilepsy patients who have had electrodes implanted on their brains in order to determine the causes of their epileptic episodes.
"When performing seizure mapping, surgeons implant electrodes in many brain areas, while searching for seizure activity,” Jacobs said. “Thus, there many electrodes end up being in normal brain tissue, and they measure neuronal activity that reflects normal brain function – this is the function that we’re studying to learn about the nature of working memory."
How connections in the brain must change to form memories could help to develop artificial cognitive computers
Exactly how memories are stored and accessed in the brain is unclear. Neuroscientists, however, do know that a primitive structure buried in the center of the brain, called the hippocampus, is a pivotal region of memory formation. Here, changes in the strengths of connections between neurons, which are called synapses, are the basis for memory formation. Networks of neurons linking up in the hippocampus are likely to encode specific memories.
Inside the unconscious brain
A new study from MIT and Massachusetts General Hospital (MGH) reveals, for the first time, what happens inside the brain as patients lose consciousness during anesthesia.
By monitoring brain activity as patients were given a common anesthetic, the researchers were able to identify a distinctive brain activity pattern that marked the loss of consciousness. This pattern, characterized by very slow oscillation, corresponds to a breakdown of communication between different brain regions, each of which experiences short bursts of activity interrupted by longer silences.
“Within a small area, things can look pretty normal, but because of this periodic silencing, everything gets interrupted every few hundred milliseconds, and that prevents any communication,” says Laura Lewis, a graduate student in MIT’s Department of Brain and Cognitive Sciences (BCS) and one of the lead authors of a paper describing the findings in the Proceedings of the National Academy of Sciences this week.
This pattern may help anesthesiologists to better monitor patients as they receive anesthesia, preventing rare cases where patients awaken during surgery or stop breathing after excessive doses of anesthesia drugs.
When people worry about math, the brain feels the pain
Mathematics anxiety can prompt a response in the brain similar to when a person experiences physical pain, according to new research at the University of Chicago.
Using brain scans, scholars determined that the brain areas active when highly math-anxious people prepare to do math overlap with the same brain areas that register the threat of bodily harm—and in some cases, physical pain.
“For someone who has math anxiety, the anticipation of doing math prompts a similar brain reaction as when they experience pain—say, burning one’s hand on a hot stove,” said Sian Beilock, professor of psychology at the University of Chicago and a leading expert on math anxiety.
Surprisingly, the researchers found it was the anticipation of having to do math, and not actually doing math itself, that looked like pain in the brain. “The brain activation does not happen during math performance, suggesting that it is not the math itself that hurts; rather the anticipation of math is painful,” added Ian Lyons, a 2012 PhD graduate in psychology from UChicago and a postdoctoral scholar at Western University in Ontario, Canada.
The two report their findings in a paper, “When Math Hurts: Math Anxiety Predicts Pain Network Activation in Anticipation of Doing Math,” in the current issue of PLOS One.