Posts tagged gray matter
Articles and news from the latest research reports.
Casual marijuana use linked to brain abnormalities in students
Young adults who used marijuana only recreationally showed significant abnormalities in two key brain regions that are important in emotion and motivation, scientists report. The study was a collaboration between Northwestern Medicine® and Massachusetts General Hospital/Harvard Medical School.
This is the first study to show casual use of marijuana is related to major brain changes. It showed the degree of brain abnormalities in these regions is directly related to the number of joints a person smoked per week. The more joints a person smoked, the more abnormal the shape, volume and density of the brain regions.
"This study raises a strong challenge to the idea that casual marijuana use isn’t associated with bad consequences," said corresponding and co-senior study author Hans Breiter, M.D. He is a professor of psychiatry and behavioral sciences at Northwestern University Feinberg School of Medicine and a psychiatrist at Northwestern Memorial Hospital.
"Some of these people only used marijuana to get high once or twice a week," Breiter said. "People think a little recreational use shouldn’t cause a problem, if someone is doing OK with work or school. Our data directly says this is not the case."
The study will be published April 16 in the Journal of Neuroscience.
Scientists examined the nucleus accumbens and the amygdala — key regions for emotion and motivation, and associated with addiction — in the brains of casual marijuana users and non-users. Researchers analyzed three measures: volume, shape and density of grey matter (i.e., where most cells are located in brain tissue) to obtain a comprehensive view of how each region was affected.
Both these regions in recreational pot users were abnormally altered for at least two of these structural measures. The degree of those alterations was directly related to how much marijuana the subjects used.
Of particular note, the nucleus acccumbens was abnormally large, and its alteration in size, shape and density was directly related to how many joints an individual smoked.
"One unique strength of this study is that we looked at the nucleus accumbens in three different ways to get a detailed and consistent picture of the problem," said lead author Jodi Gilman, a researcher in the Massachusetts General Center for Addiction Medicine and an instructor in psychology at Harvard Medical School. "It allows a more nuanced picture of the results."
Examining the three different measures also was important because no single measure is the gold standard. Some abnormalities may be more detectable using one type of neuroimaging analysis method than another. Breiter said the three measures provide a multidimensional view when integrated together for evaluating the effects of marijuana on the brain.
"These are core, fundamental structures of the brain," said co-senior study author Anne Blood, director of the Mood and Motor Control Laboratory at Massachusetts General and assistant professor of psychiatry at Harvard Medical School. "They form the basis for how you assess positive and negative features about things in the environment and make decisions about them."
Through different methods of neuroimaging, scientists examined the brains of young adults, ages 18 to 25, from Boston-area colleges; 20 who smoked marijuana and 20 who didn’t. Each group had nine males and 11 females. The users underwent a psychiatric interview to confirm they were not dependent on marijuana. They did not meet criteria for abuse of any other illegal drugs during their lifetime.
The changes in brain structures indicate the marijuana users’ brains are adapting to low-level exposure to marijuana, the scientists said.
The study results fit with animal studies that show when rats are given tetrahydrocannabinol (THC) their brains rewire and form many new connections. THC is the mind-altering ingredient found in marijuana.
"It may be that we’re seeing a type of drug learning in the brain," Gilman said. "We think when people are in the process of becoming addicted, their brains form these new connections."
In animals, these new connections indicate the brain is adapting to the unnatural level of reward and stimulation from marijuana. These connections make other natural rewards less satisfying.
"Drugs of abuse can cause more dopamine release than natural rewards like food, sex and social interaction," Gilman said. "In those you also get a burst of dopamine but not as much as in many drugs of abuse. That is why drugs take on so much salience, and everything else loses its importance."
The brain changes suggest that structural changes to the brain are an important early result of casual drug use, Breiter said. “Further work, including longitudinal studies, is needed to determine if these findings can be linked to animal studies showing marijuana can be a gateway drug for stronger substances,” he noted.
Because the study was retrospective, researchers did not know the THC content of the marijuana, which can range from 5 to 9 percent or even higher in the currently available drug. The THC content is much higher today than the marijuana during the 1960s and 1970s, which was often about 1 to 3 percent, Gilman said.
Marijuana is the most commonly used illicit drug in the U.S. with an estimated 15.2 million users, the study reports, based on the National Survey on Drug Use and Health in 2008. The drug’s use is increasing among adolescents and young adults, partially due to society’s changing beliefs about cannabis use and its legal status.
A recent Northwestern study showed chronic use of marijuana was linked to brain abnormalities. “With the findings of these two papers,” Breiter said, “I’ve developed a severe worry about whether we should be allowing anybody under age 30 to use pot unless they have a terminal illness and need it for pain.”
(Source: eurekalert.org)
Family problems experienced in childhood and adolescence affect brain development
New research has revealed that exposure to common family problems during childhood and early adolescence affects brain development, which could lead to mental health issues in later life.
The study led by Dr Nicholas Walsh, lecturer in developmental psychology at the University of East Anglia, used brain imaging technology to scan teenagers aged 17-19. It found that those who experienced mild to moderate family difficulties between birth and 11 years of age had developed a smaller cerebellum, an area of the brain associated with skill learning, stress regulation and sensory-motor control. The researchers also suggest that a smaller cerebellum may be a risk indicator of psychiatric disease later in life, as it is consistently found to be smaller in virtually all psychiatric illnesses.
Previous studies have focused on the effects of severe neglect, abuse and maltreatment in childhood on brain development. However the aim of this research was to determine the impact, in currently healthy teenagers, of exposure to more common but relatively chronic forms of ‘family-focused’ problems. These could include significant arguments or tension between parents, lack of affection or communication between family members, physical or emotional abuse, and events which had a practical impact on daily family life and might have resulted in health, housing or school problems.
Dr Walsh, from UEA’s School of Psychology, said: “These findings are important because exposure to adversities in childhood and adolescence is the biggest risk factor for later psychiatric disease. Also, psychiatric illnesses are a huge public health problem and the biggest cause of disability in the world.
“We show that exposure in childhood and early adolescence to even mild to moderate family difficulties, not just severe forms of abuse, neglect and maltreatment, may affect the developing adolescent brain. We also argue that a smaller cerebellum may be an indicator of mental health issues later on. Reducing exposure to adverse social environments during early life may enhance typical brain development and reduce subsequent mental health risks in adult life.”
The study, which was conducted with the University of Cambridge and the Medical Research Council Cognition and Brain Sciences Unit, Cambridge, is published in the journal NeuroImage: Clinical.
The 58 teenagers who took part in the brain scanning were drawn from a larger study of 1200 young people, whose parents were asked to recall any negative life events their children had experienced between birth and 11 years of age. The interviews took place when the children were aged 14 and of the 58, 27 were classified as having been exposed to childhood adversities. At ages 14 and 17 the teenagers themselves also reported any negative events and difficulties they, their family or closest friends had experienced during the previous 12 months.
A “significant and unexpected” finding was that the participants who reported stressful experiences when aged 14 were subsequently found to have increased volume in more regions of the brain when they were scanned aged 17-19. Dr Walsh said this could mean that mild stress occurring later in development may ‘inoculate’ teenagers, enabling them to cope better with exposure to difficulties in later life, and that it is the severity and timing of the experiences that may be important.
“This study helps us understand the mechanisms in the brain by which exposure to problems in early-life leads to later psychiatric issues,” said Dr Walsh. “It not only advances our understanding of how the general psychosocial environment affects brain development, but also suggests links between specific regions of the brain and individual psychosocial factors. We know that psychiatric risk factors do not occur in isolation but rather cluster together, and using a new technique we show how the general clustering of adversities affects brain development.”
The researchers also found at that those who had experienced family problems were more likely to have had a diagnosed psychiatric illness, have a parent with a mental health disorder and have negative perceptions of their how their family functioned.
Understanding the basic biology of bipolar disorder
Scientists know there is a strong genetic component to bipolar disorder, but they have had an extremely difficult time identifying the genes that cause it. So, in an effort to better understand the illness’s genetic causes, researchers at UCLA tried a new approach.
Instead of only using a standard clinical interview to determine whether individuals met the criteria for a clinical diagnosis of bipolar disorder, the researchers combined the results from brain imaging, cognitive testing, and an array of temperament and behavior measures. Using the new method, UCLA investigators — working with collaborators from UC San Francisco, Colombia’s University of Antioquia and the University of Costa Rica — identified about 50 brain and behavioral measures that are both under strong genetic control and associated with bipolar disorder. Their discoveries could be a major step toward identifying the specific genes that contribute to the illness.
The results are published in the Feb. 12 edition of the journal JAMA Psychiatry.
A severe mental illness that affects about 1 to 2 percent of the population, bipolar disorder causes unusual shifts in mood and energy, and it interferes with the ability to carry out everyday tasks. Those with the disorder can experience tremendous highs and extreme lows — to the point of not wanting to get out of bed when they’re feeling down. The genetic causes of bipolar disorder are highly complex and likely involve many different genes, said Carrie Bearden, a senior author of the study and an associate professor of psychiatry and psychology at the UCLA Semel Institute for Neuroscience and Human Behavior.
"The field of psychiatric genetics has long struggled to find an effective approach to begin dissecting the genetic basis of bipolar disorder," Bearden said. "This is an innovative approach to identifying genetically influenced brain and behavioral measures that are more closely tied to the underlying biology of bipolar disorder than the clinical symptoms alone are."
The researchers assessed 738 adults, 181 of whom have severe bipolar disorder. They used high-resolution 3-D images of the brain, questionnaires evaluating temperament and personality traits of individuals diagnosed with bipolar disorder and their non-bipolar relatives, and an extensive battery of cognitive tests assessing long-term memory, attention, inhibitory control and other neurocognitive abilities.
Approximately 50 of these measures showed strong evidence of being influenced by genetics. Particularly interesting was the discovery that the thickness of the gray matter in the brain’s temporal and prefrontal regions — the structures that are critical for language and for higher-order cognitive functions like self-control and problem-solving — were the most promising candidate traits for genetic mapping, based on both their strong genetic basis and association with the disease.
"These findings are really just the first step in getting us a little closer to the roots of bipolar disorder," Bearden said. "What was really exciting about this project was that we were able to collect the most extensive set of traits associated with bipolar disorder ever assessed within any study sample. These data will be a really valuable resource for the field."
The individuals assessed in this study are members of large families living in Costa Rica’s central valley and Antioquia, Colombia. The families were founded by European and native Amerindian populations about 400 years ago and have a very high incidence of bipolar disorder. The groups were chosen because they have remained fairly isolated since their founding and their genetics are therefore simpler for scientists to study than those of general populations.
The fact that the findings aligned so closely with those of previous, smaller studies in other populations was surprising even to the scientists, given the subjects’ unique genetic background and living environments.
"This suggests that even if the specific genetic variants we identify may be unique to this population, the biological pathways they disrupt are likely to also influence disease risk in other populations," Bearden said.
The researchers’ next step is to use the genomic data they collected from the families — including full genome sequences and gene expression data— to begin identifying the specific genes that contribute to risk for bipolar disorder. The researchers also plan to extend their investigation into the children and teens in these families. They hypothesize that many of the bipolar-related brain and behavioral differences found in adults with bipolar disorder had their origins in adolescent neurodevelopment.
Scientists identify gene linking brain structure to intelligence
For the first time, scientists at King’s College London have identified a gene linking the thickness of the grey matter in the brain to intelligence. The study is published today in Molecular Psychiatry and may help scientists understand biological mechanisms behind some forms of intellectual impairment.
The researchers looked at the cerebral cortex, the outermost layer of the human brain. It is known as ‘grey matter’ and plays a key role in memory, attention, perceptual awareness, thought, language and consciousness. Previous studies have shown that the thickness of the cerebral cortex, or ‘cortical thickness’, closely correlates with intellectual ability, however no genes had yet been identified.
An international team of scientists, led by King’s, analysed DNA samples and MRI scans from 1,583 healthy 14 year old teenagers, part of the IMAGEN cohort. The teenagers also underwent a series of tests to determine their verbal and non-verbal intelligence.
Dr Sylvane Desrivières, from the MRC Social, Genetic and Developmental Psychiatry Centre at King’s College London’s Institute of Psychiatry and lead author of the study, said: “We wanted to find out how structural differences in the brain relate to differences in intellectual ability. The genetic variation we identified is linked to synaptic plasticity – how neurons communicate. This may help us understand what happens at a neuronal level in certain forms of intellectual impairments, where the ability of the neurons to communicate effectively is somehow compromised.”
She adds: “It’s important to point out that intelligence is influenced by many genetic and environmental factors. The gene we identified only explains a tiny proportion of the differences in intellectual ability, so it’s by no means a ‘gene for intelligence’.”
The researchers looked at over 54,000 genetic variants possibly involved in brain development. They found that, on average, teenagers carrying a particular gene variant had a thinner cortex in the left cerebral hemisphere, particularly in the frontal and temporal lobes, and performed less well on tests for intellectual ability. The genetic variation affects the expression of the NPTN gene, which encodes a protein acting at neuronal synapses and therefore affects how brain cells communicate.
To confirm their findings, the researchers studied the NPTN gene in mouse and human brain cells. The researchers found that the NPTN gene had a different activity in the left and right hemispheres of the brain, which may cause the left hemisphere to be more sensitive to the effects of NPTN mutations. Their findings suggest that some differences in intellectual abilities can result from the decreased function of the NPTN gene in particular regions of the left brain hemisphere.
The genetic variation identified in this study only accounts for an estimated 0.5% of the total variation in intelligence. However, the findings may have important implications for the understanding of biological mechanisms underlying several psychiatric disorders, such as schizophrenia, autism, where impaired cognitive ability is a key feature of the disorder.
(Source: kcl.ac.uk)
How our brain networks: Research reveals white matter ‘scaffold’ of human brain
For the first time, neuroscientists have systematically identified the white matter “scaffold” of the human brain, the critical communications network that supports brain function.
Their work, published Feb. 11 in the open-source journal Frontiers in Human Neuroscience, has major implications for understanding brain injury and disease. By detailing the connections that have the greatest influence over all other connections, the researchers offer not only a landmark first map of core white matter pathways, but also show which connections may be most vulnerable to damage.
"We coined the term white matter ‘scaffold’ because this network defines the information architecture which supports brain function," said senior author John Darrell Van Horn of the USC Institute for Neuroimaging and Informatics and the Laboratory of Neuro Imaging at USC.
"While all connections in the brain have their importance, there are particular links which are the major players," Van Horn said.
Using MRI data from a large sample of 110 individuals, lead author Andrei Irimia, also of the USC Institute for Neuroimaging and Informatics, and Van Horn systematically simulated the effects of damaging each white matter pathway.
They found that the most important areas of white and gray matter don’t always overlap. Gray matter is the outermost portion of the brain containing the neurons where information is processed and stored. Past research has identified the areas of gray matter that are disproportionately affected by injury.
But the current study shows that the most vulnerable white matter pathways – the core “scaffolding” – are not necessarily just the connections among the most vulnerable areas of gray matter, helping explain why seemingly small brain injuries may have such devastating effects.
"Sometimes people experience a head injury which seems severe but from which they are able to recover. On the other hand, some people have a seemingly small injury which has very serious clinical effects," says Van Horn, associate professor of neurology at the Keck School of Medicine of USC. "This research helps us to better address clinical challenges such as traumatic brain injury and to determine what makes certain white matter pathways particularly vulnerable and important."
The researchers compare their brain imaging analysis to models used for understanding social networks. To get a sense of how the brain works, Irimia and Van Horn did not focus only on the most prominent gray matter nodes – which are akin to the individuals within a social network. Nor did they merely look at how connected those nodes are.
Rather, they also examined the strength of these white matter connections, i.e. which connections seemed to be particularly sensitive or to cause the greatest repercussions across the network when removed. Those connections which created the greatest changes form the network “scaffold.”
"Just as when you remove the internet connection to your computer you won’t get your email anymore, there are white matter pathways which result in large scale communication failures in the brain when damaged," Van Horn said.
When white matter pathways are damaged, brain areas served by those connections may wither or have their functions taken over by other brain regions, the researchers explain. Irimia and Van Horn’s research on core white matter connections is part of a worldwide scientific effort to map the 100 billion neurons and 1,000 trillion connections in the living human brain, led by the Human Connectome Project and the Laboratory of Neuro Imaging at USC.
Irimia notes that, “these new findings on the brain’s network scaffold help inform clinicians about the neurological impacts of brain diseases such as multiple sclerosis, Alzheimer’s disease, as well as major brain injury. Sports organizations, the military and the US government have considerable interest in understanding brain disorders, and our work contributes to that of other scientists in this exciting era for brain research.”
Brain structure shows affinity with numbers
The structure of the brain shows the way in which we process numbers. People either do this spatially or non-spatially. A study by Florian Krause from the Donders Institute in Nijmegen shows for the first time that these individual differences have a structural basis in the brain. The Journal of Cognitive Neuroscience published the results in an early access version of the article.
People who process numbers spatially do this using an imaginary horizontal line along which the numbers are arranged from low to high, left to right. A non-spatial representation is also possible, by comparing numbers to other magnitudes such as force or luminosity.
Different grey matter volumes
Florian Krause identified this predisposition to spatial or non-spatial number processing in MRI scans of test subjects. He discovered differences in grey matter volume, which contains the cell bodies of nerve cells, in two specific locations. Spatially oriented brains have an above-average grey matter volume in the right precuneus, a small area of the brain associated with processing visual-spatial information. Non-spatially oriented brains have more grey matter in the left angular gyrus, an area associated with semantic and conceptual processing.
Spatial numbers
For a long time, scientists thought that everyone processed numbers predominantly in a spatial way. Krause demonstrates that this is not the case. In his own words: ‘Our current study stresses the importance of non-spatial number representations. This is important since researchers in the field tend to focus mainly on spatial representations. Personally, I think that numbers are understood in terms of our body experiences. We use information about size in real life to understand number size in our heads.’
Classifying numbers
The thirty people taking part in the study were put into an MRI scanner and were shown numbers between 1 and 9 (except 5). In two consecutive judgement tasks, they had to classify the presented digits as odd or even. Both tasks differed only in the required response: in the spatial task subjects had to click with their index finger or middle finger to classify the digits, and in the non-spatial task they applied either a small or a large force on a pressure sensor with their thumb. Both tests were carried out using the right hand. Importantly, participants coupled the spatial response as well as the force response to the size of the presented number, as they responded faster with a left or soft press for small numbers and with a right or hard press for large numbers. Krause worked out those couplings for each subject, and compared the scores with the information from their brain scan.
Potential benefits for teaching maths
At present, maths is largely taught on the basis of a spatial number processing. ‘People with a non-spatial representation of numbers would probably benefit from a different approach to maths teaching’, says Krause. ‘It is possible to let pupils experience the size of numbers in a non-spatial way. This could involve expressing numbers with your body while doing simple arithmetics, for example.’ Krause is planning several new studies to explore the scientific basis of methods like these in more detail.
MR Spectroscopy Shows Differences in Brains of Preterm Infants
Premature birth appears to trigger developmental processes in the white matter of the brain that could put children at higher risk of problems later in life, according to a study being presented next week at the annual meeting of the Radiological Society of North America (RSNA).
Preterm infants—generally those born 23 to 36 weeks after conception, as opposed to the normal 37- to 42-week gestation—face an increased risk of behavioral problems, ranging from impulsiveness and distractibility to more serious conditions like autism and attention deficit hyperactivity disorder (ADHD).
"In the United States, we have approximately 500,000 preterm births a year," said Stefan Blüml, Ph.D., director of the New Imaging Technology Lab at Children’s Hospital Los Angeles and associate professor of research radiology at the University of Southern California in Los Angeles. "About 60,000 of these babies are at high risk for significant long-term problems, which means that this is a significant problem with enormous costs."
Dr. Blüml and colleagues have been studying preterm infants to learn more about how premature birth might cause changes in brain structure that may be associated with clinical problems observed later in life. Much of the focus has been on the brain’s white matter, which transmits signals and enables communication between different parts of the brain. While some white matter damage is readily apparent on structural magnetic resonance imaging (MRI), Dr. Blüml’s group has been using magnetic resonance spectroscopy (MRS) to look at differences on a microscopic level.
In this study, the researchers compared the concentrations of certain chemicals associated with mature white matter and gray matter in 51 full-term and 30 preterm infants. The study group had normal structural MRI findings, but MRS results showed significant differences in the biochemical maturation of white matter between the term and preterm infants, suggesting a disruption in the timing and synchronization of white and gray matter maturation. Gray matter is the part of the brain that processes and sends out signals.
"The road map of brain development is disturbed in these premature kids," Dr. Blüml said. "White matter development had an early start and was ‘out of sync’ with gray matter development."
This false start in white matter development is triggered by events after birth, according to Dr. Blüml.
"This timeline of events might be disturbed in premature kids because there are significant physiological switches at birth, as well as stimulatory events, that happen irrespective of gestational maturity of the newborn," he said. "The most apparent change is the amount of oxygen that is carried by the blood."
Dr. Blüml said that the amount of oxygen delivered to the fetus’s developing brain in utero is quite low, and our brains have evolved to optimize development in that low oxygen environment. However, when infants are born, they are quickly exposed to a much more oxygen-rich environment.
"This change may be something premature brains are not ready for," he said.
While this change may cause irregularities in white matter development, Dr. Blüml noted that the newborn brain has a remarkable capacity to adapt or even “re-wire” itself—a concept known as plasticity. Plasticity not only allows the brain to govern new skills over the course of development, like learning to walk and read, but could also make the brains of preterm infants and young children more responsive to therapeutic interventions, particularly if any abnormalities are identified early.
"Our research points to the need to better understand the impact of prematurity on the timing of critical maturational processes and to develop therapies aimed at regulating brain development," Dr. Blüml said.
(Source: www2.rsna.org)
Navigational ability is visible in the brain
The brains of people who immediately know their way after travelling along as a passenger are different from the brains of people who always need a GPS system or a map to get from one place to another. This was demonstrated by Joost Wegman, who will defend his thesis at Radboud University Nijmegen, the Netherlands on the 27th of November.
Wegman demonstrates that good navigators store relevant landmarks automatically on their way. Bad navigators on the other hand, often follow a fixed procedure or route (such as: turn left twice, then turn right at the statue).
Anatomical differences
Wegman also found that there are detectable structural differences between the brains of good and bad navigators. ‘These anatomical differences are not huge, but we found them significant enough, because we had a lot of data’, the researcher explains. ‘The difference is in the hippocampus. We saw that good navigators had more so-called gray matter. In the brain’s gray matter information is processed. Bad navigators, on the other hand, have more white matter - which connects gray matter areas with each other - in a brain area called the caudate nucleus. This area stores spatial actions with respect to oneself. For example, to turn right at the record store’, Wegman describes.
Questionnaires
For his research, Wegman combined data from several studies done by the Radboud University research group Neural Correlates of Spatial Memory at the Donders Institute for Brain, Cognition and Behaviour.
Wegman: ‘We always give participants extensive questionnaires in our studies. This allows us to explain possible differences in behaviour afterwards. People generally have a good insight into their ability to find their way, so these questions provide a feasible way to assess these abilities. I have coupled the answers of these questionnaires with the brain scans we have collected over the years, which allowed us to detect these differences’.
Objects in space - the neural basis of landmark-based navigation and individual differences in navigational ability (PhD defence)
Wednesday 27 November 2013, promotors: prof. dr. L.T.W. Verhoeven, prof. dr. P. Hagoort,
copromotor: dr. G. Janzen
The papers to which this article refers are both included in Joost Wegman’s thesis:
1. Wegman, J. & Janzen, G. Neural encoding of objects relevant for navigation and resting state correlations with navigational ability. Journal of Cognitive Neuroscience 23, 3841-3854 (2011).
2. Wegman, J. et al. Gray and white matter correlates of navigational ability in humans. Human Brain Mapping (in press).
Brain Still Injured from Concussion After Symptoms Fade
After a mild concussion, special brain scans show evidence of brain abnormalities four months later, when symptoms from the concussion have mostly dissipated, according to research published in the November 20, 2013, online issue of Neurology®, the medical journal of the American Academy of Neurology.
“These results suggest that there are potentially two different modes of recovery for concussion, with the memory, thinking and behavioral symptoms improving more quickly than the physiological injuries in the brain,” said study author Andrew R. Mayer, PhD, of the Mind Research Network and University of New Mexico School of Medicine in Albuquerque.
Mayer further suggests that healing from concussions may be similar to other body ailments such as recovering from a burn. “During recovery, reported symptoms like pain are greatly reduced before the body is finished healing, when the tissue scabs. These finding may have important implications about when it is truly safe to resume physical activities that could produce a second concussion, potentially further injuring an already vulnerable brain.”
Mayer noted that standard brain scans such as CT or MRI would not pick up on these subtle changes in the brain. “Unfortunately, this can lead to the common misperception that any persistent symptoms are psychological.”
The study compared 50 people who had suffered a mild concussion to 50 healthy people of similar age and education. All the participants had tests of their memory and thinking skills and other symptoms such as anxiety and depression two weeks after the concussion, as well as brain scans. Four months after the concussion, 26 of the patients and 26 controls repeated the tests and scans.
The study found that two weeks after the injury the people who had concussions had more self-reported problems with memory and thinking skills, physical problems such as headaches and dizziness, and emotional problems such as depression and anxiety than people who had not had concussions. By four months after the injury, the symptoms were significantly reduced by up to 27 percent.
The people who had concussions also had evidence of abnormalities in the gray matter in the frontal cortex area of both sides of the brain, based on the diffusion tensor imaging scans. The increase equated to about 10 percent compared to the healthy people in the study. These abnormalities were still apparent four months after the concussion. In contrast, there was no evidence of cellular loss on scans.
Mayer said possible explanations for the brain abnormalities could be cytotoxic edema, which results from changes in where fluids are located in and around brain cells, or reactive gliosis, which is the change in glial cells’ shape in response to damage to the central nervous system.
How video gaming can be beneficial for the brain
Video gaming causes increases in the brain regions responsible for spatial orientation, memory formation and strategic planning as well as fine motor skills. This has been shown in a new study conducted at the Max Planck Institute for Human Development and Charité University Medicine St. Hedwig-Krankenhaus. The positive effects of video gaming may also prove relevant in therapeutic interventions targeting psychiatric disorders.
In order to investigate how video games affect the brain, scientists in Berlin have asked adults to play the video game “Super Mario 64” over a period of two months for 30 minutes a day. A control group did not play video games. Brain volume was quantified using magnetic resonance imaging (MRI). In comparison to the control group the video gaming group showed increases of grey matter, in which the cell bodies of the nerve cells of the brain are situated. These plasticity effects were observed in the right hippocampus, right prefrontal cortex and the cerebellum. These brain regions are involved in functions such as spatial navigation, memory formation, strategic planning and fine motor skills of the hands. Most interestingly, these changes were more pronounced the more desire the participants reported to play the video game.
“While previous studies have shown differences in brain structure of video gamers, the present study can demonstrate the direct causal link between video gaming and a volumetric brain increase. This proves that specific brain regions can be trained by means of video games”, says study leader Simone Kühn, senior scientist at the Center for Lifespan Psychology at the Max Planck Institute for Human Development. Therefore Simone Kühn and her colleagues assume that video games could be therapeutically useful for patients with mental disorders in which brain regions are altered or reduced in size, e.g. schizophrenia, post-traumatic stress disorder or neurodegenerative diseases such as Alzheimer’s dementia.
“Many patients will accept video games more readily than other medical interventions”, adds the psychiatrist Jürgen Gallinat, co-author of the study at Charité University Medicine St. Hedwig-Krankenhaus. Further studies to investigate the effects of video gaming in patients with mental health issues are planned. A study on the effects of video gaming in the treatment of post-traumatic stress disorder is currently ongoing.