Posts tagged neuroscience
Articles and news from the latest research reports.
Your Brain Sees Things You Don’t
University of Arizona doctoral degree candidate Jay Sanguinetti has authored a new study, published online in the journal Psychological Science, that indicates that the brain processes and understands visual input that we may never consciously perceive.
The finding challenges currently accepted models about how the brain processes visual information.
A doctoral candidate in the UA’s Department of Psychology in the College of Science, Sanguinetti showed study participants a series of black silhouettes, some of which contained meaningful, real-world objects hidden in the white spaces on the outsides.
Saguinetti worked with his adviser Mary Peterson, a professor of psychology and director of the UA’s Cognitive Science Program, and with John Allen, a UA Distinguished Professor of psychology, cognitive science and neuroscience, to monitor subjects’ brainwaves with an electroencephalogram, or EEG, while they viewed the objects.
"We were asking the question of whether the brain was processing the meaning of the objects that are on the outside of these silhouettes," Sanguinetti said. "The specific question was, ‘Does the brain process those hidden shapes to the level of meaning, even when the subject doesn’t consciously see them?"
The answer, Sanguinetti’s data indicates, is yes.
Study participants’ brainwaves indicated that even if a person never consciously recognized the shapes on the outside of the image, their brains still processed those shapes to the level of understanding their meaning.
"There’s a brain signature for meaningful processing," Sanguinetti said. A peak in the averaged brainwaves called N400 indicates that the brain has recognized an object and associated it with a particular meaning.
"It happens about 400 milliseconds after the image is shown, less than a half a second," said Peterson. "As one looks at brainwaves, they’re undulating above a baseline axis and below that axis. The negative ones below the axis are called N and positive ones above the axis are called P, so N400 means it’s a negative waveform that happens approximately 400 milliseconds after the image is shown."
The presence of the N400 peak indicates that subjects’ brains recognize the meaning of the shapes on the outside of the figure.
"The participants in our experiments don’t see those shapes on the outside; nonetheless, the brain signature tells us that they have processed the meaning of those shapes," said Peterson. "But the brain rejects them as interpretations, and if it rejects the shapes from conscious perception, then you won’t have any awareness of them."
"We also have novel silhouettes as experimental controls," Sanguinetti said. "These are novel black shapes in the middle and nothing meaningful on the outside."
The N400 waveform does not appear on the EEG of subjects when they are seeing truly novel silhouettes, without images of any real-world objects, indicating that the brain does not recognize a meaningful object in the image.
"This is huge," Peterson said. "We have neural evidence that the brain is processing the shape and its meaning of the hidden images in the silhouettes we showed to participants in our study."
The finding leads to the question of why the brain would process the meaning of a shape when a person is ultimately not going to perceive it, Sanguinetti said.
"The traditional opinion in vision research is that this would be wasteful in terms of resources," he explained. "If you’re not going to ultimately see the object on the outside why would the brain waste all these processing resources and process that image up to the level of meaning?"
"Many, many theorists assume that because it takes a lot of energy for brain processing, that the brain is only going to spend time processing what you’re ultimately going to perceive," added Peterson. "But in fact the brain is deciding what you’re going to perceive, and it’s processing all of the information and then it’s determining what’s the best interpretation."
"This is a window into what the brain is doing all the time," Peterson said. "It’s always sifting through a variety of possibilities and finding the best interpretation for what’s out there. And the best interpretation may vary with the situation."
Our brains may have evolved to sift through the barrage of visual input in our eyes and identify those things that are most important for us to consciously perceive, such as a threat or resources such as food, Peterson suggested.
In the future, Peterson and Sanguinetti plan to look for the specific regions in the brain where the processing of meaning occurs.
"We’re trying to look at exactly what brain regions are involved," said Peterson. "The EEG tells us this processing is happening and it tells us when it’s happening, but it doesn’t tell us where it’s occurring in the brain."
"We want to look inside the brain to understand where and how this meaning is processed," said Peterson.
Images were shown to Sanguinetti’s study participants for only 170 milliseconds, yet their brains were able to complete the complex processes necessary to interpret the meaning of the hidden objects.
"There are a lot of processes that happen in the brain to help us interpret all the complexity that hits our eyeballs," Sanguinetti said. "The brain is able to process and interpret this information very quickly."
Sanguinetti’s study indicates that in our everyday life, as we walk down the street, for example, our brains may recognize many meaningful objects in the visual scene, but ultimately we are aware of only a handful of those objects.
The brain is working to provide us with the best, most useful possible interpretation of the visual world, Sanguinetti said, an interpretation that does not necessarily include all the information in the visual input.
Reduced cognitive control in passionate lovers
People who are in love are less able to focus and to perform tasks that require attention. Researcher Henk van Steenbergen concludes this, together with colleagues from Leiden University and the University of Maryland. The article has appeared in the journal Motivation and Emotion.
The more in love, the less focused you are
Forty-three participants who had been in a relationship for less than half a year performed a number of tasks during which they had to discriminate irrelevant from relevant information as soon as possible. It appeared that the more in love they were, the less able they were to ignore the irrelevant information. Love intensity thus was related to how well someone is able to focus. There was no difference between men and women.
Cognitive control
The participants listened to music that elicited romantic feelings and thought of a romantic event to intensify their love feelings. Participants also completed a questionnaire that was used to assess the intensity of their love feelings. The results of the study by Henk van Steenbergen differed from results from previous studies. Those previous studies showed that the ability to ignore distracting information is required to maintain a long-term romantic relationship. Being able to control oneself (also called “cognitive control”) and to resist temptations that could threaten the relationship is essential in long-term love.
Thinking of your beloved
In the study by Van Steenbergen, in contrast, the participants had become involved in a romantic relationship only a few months ago. “When you have just become involved in a romantic relationship you’ll probably find it harder to focus on other things because you spend a large part of your cognitive resources on thinking of your beloved”, Van Steenbergen says. “For long-lasting love in a long-term relationship, on the other hand, it seems crucial to have proper cognitive control.” Over time, a balance between less and more cognitive control may be critical for a successful relationship.
Why is romantic love associated with cognitive control?
Van Steenbergen emphasizes that the link between romantic love and cognitive control is a new area of research. “The reason why romantic love is associated with cognitive control is still unknown. It could be that lovers use all their cognitive resources to think about their beloved, which leaves them no resources to perform a boring task. It could also be that the association goes in the opposite direction: people who have reduced cognitive control may experience more intense love feelings than people who have higher levels of cognitive control.” Future research will have to clarify this.
(Source: news.leiden.edu)
What do bullies and sex have in common? Based on work by scientists at the European Molecular Biology Laboratory (EMBL) in Monterotondo, Italy, it seems that the same part of the brain reacts to both. In a study published today in Nature Neuroscience, the researchers found that – at least in mice – different types of fear are processed by different groups of neurons, even if the animals act out those fears in the same way. The findings could have implications for addressing phobias and panic attacks in humans.
“We found that there seems to be a circuit for handling fear of predators – which has been described anatomically as a kind of defence circuit – but fear of members of the same species uses the reproductive circuit instead,” says Bianca Silva, who carried out the work, “and fear of pain goes through yet another part of the brain.”
Working in the lab of Cornelius Gross at EMBL, Silva exposed mice to three threats: another mouse (chosen for being particularly aggressive), a rat (the mouse’s natural predator) or a mild electric shock to the feet. The mice showed the same typical fearful behaviours – running away, freezing – in response to all threats, but their brains painted a different picture. When the scientists mapped the brain activity of mice exposed to the aggressive mouse and the rat, they saw that different parts of a region called the ventromedial hypothalamus (VMH) ‘lit up’ depending on the threat. Fear of the mouse seemed to activate the bottom and sides of the VMH, while fear of the rat seemed to be processed by the VMH’s central and upper areas. This was confirmed when the scientists used drugs to block only the neurons in those ‘rat fear’ areas: mice were no longer afraid of the rat, but were still afraid of the mouse, showing that mice need this brain circuit specifically to process fear of predators.
The human brain has similar circuits, and we too experience different kinds of fear, so the results hint at the possibility of developing more efficient treatments for specific phobias or panic attacks, by targeting only the relevant region of the brain.
For their part, the EMBL scientists plan to probe these fears further.
“What we’re interested in, in the long-run, is if these results represent a kind of mental state,” says Cornelius Gross, who led the work. “If so, mice should be able to be in that state without expressing it in their behaviour – do they re-live that fear, for example? These are not easy questions to ask in the mouse, but we’re looking into them.”
Gross’s lab are also looking at how these different fears – and the neural circuits that process them – may have evolved. Working with Detlev Arendt’s group at EMBL Heidelberg, they have discovered a similar brain region in a marine worm thought to closely resemble our ancestors from 600 million years ago. Now the team is exploring the possibility that this represents an ancestral core fear circuit that those ancestors handed down to us all, from worms to man.
Study Examines Amyloid Deposition in Patients with Traumatic Brain Injury
Patients with traumatic brain injury (TBI) had increased deposits of β-Amyloid (Αβ) plaques, a hallmark of Alzheimer Disease (AD), in some areas of their brains in a study by Young T. Hong, Ph.D., of the University of Cambridge, England, and colleagues.
There may be epidemiological or pathophysiological (changes because of injury) links between TBI and AD, and Αβ plaques are found in as many as 30 percent of patients who die in the acute phase after a TBI. The plaques appear within hours of the injury and can occur in patients of all ages, according to the study background.
Researchers used imaging and brain tissue acquired during autopsies to examine Αβ deposition in patients with TBI. Researchers performed positron emission tomography (PET) imaging using carbon 11-labeled Pittsburgh Compound B ([11C]PIB), a marker of brain amyloid deposition, in 15 participants with a TBI and 11 healthy patients. Autopsy-acquired brain tissue was obtained from 16 people who had a TBI, as well as seven patients with a nonneurological cause of death.
The study’s findings indicate that patients with TBI showed increases in [11C]PIB binding, which may be a marker of Αβ plaque in some areas of the brain.
“The use of ([11C]PIB PET for amyloid imaging following TBI provides us with the potential for understanding the pathophysiology of TBI, for characterizing the mechanistic drivers of disease progression or suboptimal recovery in the subacute phase of TBI, for identifying patients at high risk of accelerated AD, and for evaluating the potential of antiamyloid therapies,” the authors conclude.
(Source: media.jamanetwork.com)
A longitudinal study of grapheme-color synaesthesia in childhood
What colour is H? Is 4 brighter than 9? For most people these questions might seem baffling, but not for people with grapheme-color synesthesia.
In the first long-term childhood study on grapheme-color synesthesia, researchers followed 80 children to determine when and how associations between graphemes and colors develop. The latest results are published in the open-access journal Frontiers in Human Neuroscience.
Grapheme-color synesthesia is a harmless, alternative form of perception caused by subtle differences in the brain – possibly, stronger connections between centers for language and color – that give letters and numbers their phantom colors. It is passed down from parent to child in around 1 to 2% of the population.
In the present study, a group of synesthete children was tested three times between 6 and 10 years old. Each child was presented with 36 graphemes – the letters A to Z and digits 0 to 9 – and asked to choose the ‘best’ of 13 colors for each.
Children with grapheme-color synesthesia had already developed strong associations for around 30% of graphemes at 6 years old. At 7 years old, the same children had associations for around 50% of graphemes, and this increased to 70% of graphemes at 10 years old. The synesthete children were consistent in their choices over this 4-year period. Three children who were synesthetes at ages 6 to 7 were no longer so at 10 years old, indicating that the condition spontaneously disappears in some children as they grow older.
"This repeated testing of child synesthetes in real time allowed us to see for the first time that synesthetic colours emerge slowly during childhood, building up an incremental inventory of colorful letters and numbers," says Dr. Simner, a cognitive neuropsychologist who specializes in synesthesia, from the University of Edinburgh, UK.
The researchers’ next challenge is to determine how changes in the intensity of synesthesia - as strengthening or loss with increasing age - can be explained from changes in the organization of the brain.
(Image: Shutterstock)
Biomaterial-delivered chemotherapy could provide final blow to brain tumours
A polymer originally designed to help mend broken bones could be successful in delivering chemotherapy drugs directly to the brains of patients suffering from brain tumours, researchers at The University of Nottingham have discovered.
Their study, published in the journal PLOS ONE, shows that the biomaterial can be easily applied to the cavity created following brain cancer surgery and used to release chemotherapy drugs over several weeks.
The targeted nature of the therapy could also reduce the toxic effects of chemotherapy drugs on healthy parts of the body, potentially reducing the debilitating side-effects that many patients experience after cancer treatment.
Patient survival
Dr Ruman Rahman, of the University’s Children’s Brain Tumour Research Centre (CBTRC), who led the study, said: “Our system is an innovative method of drug delivery for the treatment of brain tumours and is intended to be administered immediately after surgery by the operating neurosurgeon.
“Ultimately, this method of drug delivery, in combination with existing therapies, may result in more effective treatment of brain tumours, prolonged patient survival and reduced morbidity.”
Brain tumours are the major cause of cancer-related death in children and adults up to the age of 40. Most relapses occur when surgeons are unable to remove all of the cancerous cells during surgery – something which can be particularly challenging in very young children and babies and by the very nature of a type of adult brain cancer called glioblastoma.
Although alternative systems for delivery of drugs directly to the brain have been developed, they are used infrequently because their success has been limited. This new drug delivery system is the first that can be moulded to the shape of the brain tumour cavity and the first to deliver several different drugs over a clinically meaningful period of time.
The Nottingham polymer formulation is made from two types of micro-particles called PLGA and PEG and has been developed and patented by leading tissue engineer Professor Kevin Shakesheff, based in the University’s School of Pharmacy. A powder at room temperature, it can be mixed to a toothpaste-like consistency with the addition of water.
Unique properties
The unique properties of the polymer lie in its ability to set into a rigid structure only when it reaches body temperature (37 degrees), a feature perfectly tailored for use in medical therapies. It was originally developed as a scaffold on to which new bone cells could be grown to speed up the knitting back together of broken bones.
Dr Ruman Rahman at the CBTRC and Dr Cheryl Rahman from the School of Pharmacy spotted the potential for the polymer to deliver chemotherapy drugs directly to patients’ brain tumours. The work was performed at the CBTRC with neurosurgeon Mr Stuart Smith and neuro-oncologist Professor Richard Grundy. The cavity left by the removal of a tumour would be lined with the polymer while in paste form, which would start to solidify and gradually release the chemotherapy drugs after the incision has been closed. This would directly target any residual cells not initially removed during surgery.
In the lab, the Nottingham scientists were able to successfully demonstrate the slow-release properties of the material by placing paste loaded with three commonly used chemotherapy drugs into a solution of saline and measuring the quantities of the drugs given out by the material over time.
To establish whether the material itself is safe to use on patients in this form of therapy, they used it to create a 3D model onto which they were able to grow brain tumour cells and healthy brain blood vessel cells without any toxicity. They then simulated surgery on a sheep’s brain from an abattoir by moulding the paste around a brain cavity and warming the brain to human body temperature to harden the polymer.
The brain was then scanned using CT and MRI technology to demonstrate that it is still possible to distinguish the polymer from normal brain tissue on a routine brain scan, an aspect crucial for doctors when dealing with follow-up care for brain tumour patients who have undergone surgery.
Robust material
The team also dealt with concerns that the material could disintegrate and release its chemotherapy contents too quickly during the subsequent radiotherapy which many cancer patients undergo following surgery. By placing the biomaterial loaded with chemotherapy drugs into a head cavity of a medical training dummy and subjecting it to the same duration and intensity of radiotherapy used for brain tumour patients they were able to successfully demonstrate the robust integrity of the structure.
Finally they showed that a chemotherapy drug called etoposide could be effective at killing brain cancer cells in a mouse when released from the polymer formulation. The next stage of the research will be to extend the study in mice with brain tumours to test whether animals with the drug-loaded polymers survive longer. The team are also investigating the release of other chemotherapeutic drugs that hold promise, supported by a recent grant award from Sparks.
As the research used a biomaterial and chemotherapy drugs already approved for medical use, many of the usual ethical approval hurdles to allow further investigation have already been cleared.
The first clinical test, anticipated in 3 years’ time, will be to devise a multi-centre phase 0 clinical trial which would involve testing the therapy on a small number of patients for whom other clinical treatments have not been successful and would otherwise only be offered palliative care.
“This is a very exciting development and holds considerable promise for the treatment of malignant brain tumours in the near future” commented Professor Grundy, Co-Director of the CBTRC.
(Source: nottingham.ac.uk)
Studies pinpoint specific brain areas and mechanisms associated with depression and anxiety
Research released today reveals new mechanisms and areas of the brain associated with anxiety and depression, presenting possible targets to understand and treat these debilitating mental illnesses. The findings were presented at Neuroscience 2013, the annual meeting of the Society for Neuroscience and the world’s largest source of emerging news about brain science and health.
More than 350 million people worldwide suffer from clinical depression and between 5 and 25 percent of adults suffer from generalized anxiety, according to the World Health Organization. The resulting emotional and financial costs to people, families, and society are significant. Further, antidepressants are not always effective and often cause severe side effects.
Today’s new findings show that:
- A molecule in the immune system may contribute to depression, suggesting a potential biomarker for the disease (Georgia Hodes, PhD, abstract 542.1, see attached summary).
- Decreasing a chemical signal in the amygdala, a brain area associated with emotional processing, produces antidepressant-like effects in mice (Yann Mineur, PhD, abstract 504, see attached summary).
- MicroRNAs, tiny molecules that alter gene expression, correlate with how mice respond to socially stressful situations that cause depressive-like behavior. The findings may help determine why some people are more likely to suffer from depression than others (Karen Scott, PhD, abstract 731.2, see attached summary).
Other recent findings discussed show that:
- A pathway between two brain regions, the amygdala and the hippocampus, plays a significant role in anxiety. Shutting down this connection can decrease anxiety-like behavior in mice (Ada Felix-Ortiz, MS, presentation 393.01, see attached speaker summary).
- Aversive experiences can change how humans, particularly those with anxiety disorders, perceive stimuli. After a severe negative incident, patients with anxiety disorders over-generalize the experience and have increased emotional responses to subsequent similar situations (Rony Paz, PhD, presentation 295.05, see attached speaker summary).
“Today’s findings represent our rapidly growing understanding of the individual molecules and brain circuits that may contribute to depression and anxiety,” said press conference moderator Lisa Monteggia, PhD, of the University of Texas Southwestern Medical Center, an expert on mechanisms of antidepressant action. “These exciting discoveries represent the potential for significant changes in how we diagnose and treat these illnesses that touch millions.”
Understanding ourselves by studying the animal kingdom
Research released today reveals a new model for a genetic eye disease, and shows how animal models — from fruit flies to armadillos and monkeys — can yield valuable information about the human brain. The findings were presented at Neuroscience 2013, the annual meeting of the Society for Neuroscience and the world’s largest source of emerging news about brain science and health.
Animal models have long been central in how we understand the human brain, behavior, and nervous system due to similarities in many brain areas and functions across species. Almost every major medical advance in the last century was made possible by carefully regulated, humane animal research. Today’s findings build on this rich history and demonstrate what animals can teach us about ourselves.
Today’s new findings show that:
- The nine-banded armadillo may serve as a model for certain types of progressive blindness. The animal’s poor eyesight mimics many human disorders and may shed light on new treatment approaches for such diseases (Christopher Emerling, BS, abstract 150.06, see attached summary).
- Analysis of a baboon population reveals particular genes that may be involved in creating the “folds” in the structure of the brain. These findings provide information on how human genes may have evolved to create the brain’s shape and function (Elizabeth Atkinson, BA, abstract 195.13, see attached summary).
- Monkeys and humans use similar brain pathways while processing decisions. Detailed analyses of similarities and differences in brain wiring could provide new insights into decision-making in humans (Franz-Xaver Neubert, abstract 18.03, see attached summary).
Other recent findings discussed show that:
- Use of powerful genetic tools in fruit flies is helping to reveal the basic building blocks of brain circuitry and function. This work is furthering our understanding of the human brain and may be helpful in developing medical diagnostic devices (Rachel Wilson, PhD, presentation 302, see attached speaker summary).
- Research in a tiny worm (C. elegans) has allowed scientists to map all of the connections between neurons in the species, including the pathways for movement, sex, and more. The findings offer new insights into how the human nervous system functions (Scott Emmons, PhD, presentation 009, see attached speaker summary).
“Neuroscience has always relied on responsible animal research to better understand how our brains and bodies develop, function, and break down,” said press conference moderator Leslie Tolbert, of the University of Arizona, whose work in insects provides insights into brain development. “Today’s studies reveal new ways that research on unlikely-seeming animals, such as armadillos, fruit flies, and worms, could have real impact on our understanding of the human brain and what can go wrong in disease.”
Research reveals new understanding, warning signs, and potential treatments for multiple sclerosis
Scientists are gaining a new level of understanding of multiple sclerosis (MS) that may lead to new treatments and approaches to controlling the chronic disease, according to new research released today at Neuroscience 2013, the annual meeting of the Society for Neuroscience and the world’s largest source of emerging news about brain science and health.
MS is a severe, often crippling, autoimmune disease caused by the body’s immune system attacking the nervous system. Today, more than two million people worldwide suffer from MS and other neuroinflammatory diseases. MS usually strikes in early adulthood and manifests with symptoms including vision loss, paralysis, numbness, and fatigue. The disease can be intermittent or progressive and currently has no cure.
Today’s new findings show that:
- Scientists are one step closer to understanding how antibodies in the blood stream break past the brain’s protective barrier to attack the optic nerves, spinal cord, and brain, causing the symptoms of neuromyelitis optica, a rare disease similar to MS. Understanding how the antibodies bypass the protective blood-brain barrier could provide new approaches to treating the disease (Yukio Takeshita, MD, PhD, abstract 404.09, see attached summary).
- A protein involved in blood clotting might serve as an early detection method for MS before symptoms occur. Early detection of the disease could lead to more effective early treatments (Katerina Akassoglou, PhD, abstract 404.11, see attached summary).
- Low levels of a cholesterol protein correlate with the severity of a patient’s MS in both human patients and mouse models. The finding suggests the protein, known to protect against inflammation, may protect against developing MS, and possibly even aid in the regeneration of damaged neurons. This research opens the door to cholesterol drugs as a possible new avenue for MS treatment (Lidia Gardner, PhD, abstract 404.01, see attached summary).
Other recent findings discussed show that:
- A type of immune system cell has been found to directly target and damage nerve cell axons, a hallmark of MS. This may reveal a target for new therapies (Brian Sauer, PhD, presentation 404.06, see attached speaker summary).
- While no treatments to rebuild cells damaged by MS currently exist, scientists have found that when exosomes — tiny, naturally occurring “nanovesicles” — are produced by dendritic cells and applied to the brain, they can deliver a mixture of proteins and RNAs that promote regeneration of protective myelin sheaths and guard against MS symptoms (Richard Kraig, MD, PhD, presentation 812.02, see attached speaker summary).
“The findings shown today represent real promise for the millions suffering from MS,” said press conference moderator Jeffrey Rothstein of Johns Hopkins University and an expert in neurodegenerative diseases. “These studies are breakthroughs in understanding and treating a disease that remains uncured, difficult to diagnose, and for which it is very difficult to prevent progression.”
Exercise during pregnancy gives newborn brain development a head start
As little as 20 minutes of moderate exercise three times per week during pregnancy enhances the newborn child’s brain development, according to researchers at the University of Montreal and its affiliated CHU Sainte-Justine children’s hospital. This head-start could have an impact on the child’s entire life. “Our research indicates that exercise during pregnancy enhances the newborn child’s brain development,” explained Professor Dave Ellemberg, who led the study. “While animal studies have shown similar results, this is the first randomized controlled trial in humans to objectively measure the impact of exercise during pregnancy directly on the newborn’s brain. We hope these results will guide public health interventions and research on brain plasticity. Most of all, we are optimistic that this will encourage women to change their health habits, given that the simple act of exercising during pregnancy could make a difference for their child’s future.” Ellemberg and his colleagues Professor Daniel Curnier and PhD candidate Élise Labonté-LeMoyne presented their findings today at the Neuroscience 2013 congress in San Diego.
Not so long ago, obstetricians would tell women to take it easy and rest during their pregnancy. Recently, the tides have turned and it is now commonly accepted that inactivity is actually a health concern. “While being sedentary increases the risks of suffering complications during pregnancy, being active can ease post-partum recovery, make pregnancy more comfortable and reduce the risk of obesity in the children,” Curier explained. “Given that exercise has been demonstrated to be beneficial for the adult’s brain, we hypothesized that it could also be beneficial for the unborn child through the mother’s actions.”
To verify this, starting at the beginning of their second trimester, women were randomly assigned to an exercise group or a sedentary group. Women in the exercise group had to perform at least 20 minutes of cardiovascular exercise three times per week at a moderate intensity, which should lead to at least a slight shortness of breath. Women in the sedentary group did not exercise. The brain activity of the newborns was assessed between the ages of 8 to 12 days, by means of electroencephalography, which enables the recording of the electrical activity of the brain. “We used 124 soft electrodes placed on the infant’s head and waited for the child to fall asleep on his or her mother’s lap. We then measured auditory memory by means of the brain’s unconscious response to repeated and novel sounds,” Labonté-LeMoyne said. “Our results show that the babies born from the mothers who were physically active have a more mature cerebral activation, suggesting that their brains developed more rapidly.”
The researchers are now in the process of evaluating the children’s cognitive, motor and language development at age 1 to verify if these differences are maintained.
(Source: nouvelles.umontreal.ca)