Posts tagged psychology
Articles and news from the latest research reports.
The Dementia and Music Project - Chloe Meineck
This project is a culmination of two years research highlighting the advantages of listening to familiar music for dementia sufferers. This coupled with the fact that when many people move into a home they feel lost in their unfamiliar surroundings. The music box, which is all hand made, combines an interactive music player, with a memory box of co-designed special objects.
The film is Barbara talking about her life, her most important objects, music, events and her most treasured people.
Is this the most unpleasant sound in the world?
The ear-splitting screech of a knife on a glass bottle has been identified as the worst sound to the human ear by scientists who studied the brain’s response to unpleasant noises.
People who listened to a series of 74 recordings while having their brain activity measured by an MRI scanner rated the sound of a fork on a glass as the second worst noise, followed by chalk on a blackboard.
The scans revealed that unpleasant sounds provoked a stronger response in the brain than pleasant ones such as the noise of blubbing water. While sounds are processed in the brain’s auditory cortex, uncomfortable noises activate the amygdala, a separate brain region which processes emotions.
The researchers studied a group of 13 volunteers and found that sounds with a frequency of between 2,000 and 5,000 Hz, the range at which our ears are the most sensitive, were the hardest to bear.
Although it remains unclear why our ears are most sensitive to this type of sound, researchers noted that screams, which we naturally find uncomfortable, fall within the same range.
Dr Sukhbinder Kumar of Newcastle University, author of the study, which was published in the Journal of Neuroscience, said: “It appears there is something very primitive kicking in. It’s a possible distress signal from the amygdala to the auditory cortex.”
His colleague Prof Tim Griffiths added: “This might be a new inroad into emotional disorders and disorders like tinnitus and migraine, in which there seems to be heightened perception of the unpleasant aspects of sounds.”
McGill researchers link genetic mutation to psychiatric disease and obesity
McGill researchers link genetic mutation to psychiatric disease and obesity
Deletion of brain-derived neurotrophic factor leads to major depression, anxiety, and obesity
McGill researchers have identified a small region in the genome that conclusively plays a role in the development of psychiatric disease and obesity. The key lies in the genomic deletion of brain-derived neurotrophic factor, or BDNF, a nervous system growth factor that plays a critical role in brain development.
To determine the role of BDNF in humans, Prof. Carl Ernst, from McGill’s Department of Psychiatry, Faculty of Medicine, screened over 35,000 people referred for genetic screening at clinics and over 30,000 control subjects in Canada, the U.S., and Europe. Overall, five individuals were identified with BDNF deletions, all of whom were obese, had a mild-moderate intellectual impairment, and had a mood disorder. Children had anxiety disorders, aggressive disorders, or attention deficit-hyperactivity disorder (ADHD), while post-pubescent subjects had anxiety and major depressive disorders. Subjects gradually gained weight as they aged, suggesting that obesity is a long-term process when BDNF is deleted.
"Scientists have been trying to find a region of the genome which plays a role in human psychopathology, searching for answers anywhere in our DNA that may give us a clue to the genetic causes of these types of disorders," says Prof. Ernst, who is also a researcher at the Douglas Mental Health University Institute. "Our study conclusively links a single region of the genome to mood and anxiety."
The findings, published in the Archives of General Psychiatry, reveal for the first time the link between BDNF deletion, cognition, and weight gain in humans. BDNF has been suspected to have many functions in the brain based on animal studies, but no study had shown what happens when BDNF is missing from the human genome. This research provides a step toward better understanding human behaviour and mood by clearly identifying genes that may be involved in mental disorders.
"Mood and anxiety can be seen like a house of cards. In this case, the walls of the house represent the myriad of biological interactions that maintain the structure," says Ernst, "Studying these moving parts can be tricky, so teasing apart even a single event is important. Linking a deletion in BDNF conclusively to mood and anxiety really tells us that it is possible to dissect the biological pathways involved in determining how we feel and act.
We now have a molecular pathway we are confident is involved in psychopathology,” adds Ernst, “Because thousands of genes are involved in mood, anxiety, or obesity, it allows us to root our studies on a solid foundation. All of the participants in our study had mild-moderate intellectual disability, but most people with these cognitive problems do not have psychiatric problems – so what is it about deletion of BDNF that affects mood? My hope now is to test the hypothesis that boosting BDNF in people with anxiety or depression might improve brain health.”
(Source: fiercebiotechresearch.com)
Dual spotlights in the brain
How we manage to attend to multiple objects without being distracted by irrelevant information
The “tiki-taka”-style of the Spanish national football team is amazing to watch: Xavi passes to Andrès Iniesta, he just rebounds the ball once and it’s right at Xabi Alonso’s foot. The Spanish midfielders cross the field as if they run on rails, always maintaining attention on the ball and the teammates, the opponents chasing after them without a chance. An international team of scientists from the German Primate Center and McGill University in Canada, including Stefan Treue, head of the Cognitive Neuroscience Laboratory, has now uncovered how the human brain makes such excellence possible by dividing visual attention: The brain is capable of splitting its ‘attentional spotlight’ for an enhanced processing of multiple visual objects. (Neuron, doi: 10.1016/j.neuron.2011.10.013)
When we pay attention to an object, neurons responsible for this location in our field of view are more active then when they process unattended objects. But quite often we want to pay attention to multiple objects in different spatial positions, with interspersed irrelevant objects. Different theories have been proposed to account for this ability. One is, that the attentive focus is split spatially, excluding objects between the attentional spotlights. Another possibility is, that the attentional focus is zoomed out to cover all relevant objects, but including the interspersed irrelevant ones. A third possibility would be a single focus rapidly switching between the attended objects.
Studying rhesus macaques
In order to explain how such a complex ability is achieved, the neuroscientists measured the activity of individual neurons in areas of the brain involved in vision. They studied two rhesus macaques, which were trained in a visual attention task. The monkeys had learned to pay attention to two relevant objects on a screen, with an irrelevant object between them. The experiment showed, that the macaques’ neurons responded strongly to the two attended objects with only a weak response to the irrelevant stimulus in the middle. So the brain is able to spatially split visual attention and ignore the areas in between. “Our results show the enormous adaptiveness of the brain, which enables us to deal effectively with many different situations.
This multi-tasking allows us to simultaneously attend multiple objects”, Stefan Treue says. Such a powerful ability of our attentive system is one precondition for humans to become perfect football-artists but also to safely navigate in everyday traffic.
(Source: alphagalileo.org)
Neuroscientists Launch 5 Year Study of Music Education and Child Brain Development
Researchers at USC Brain and Creativity Institute will explore the effects of intense music training on cognitive development in LA Phil’s YOLA at HOLA program.
The Los Angeles Philharmonic Association, the USC Brain and Creativity Institute and Heart of Los Angeles (HOLA) are delighted to announce a longitudinal research collaboration to investigate the emotional, social and cognitive effects of musical training on childhood brain development.
The five-year research project, Effects of Early Childhood Musical Training on Brain and Cognitive Development, will offer USC researchers an important opportunity to provide new insights and add rigorous data to an emerging discussion about the role of early music engagement in learning and brain function.
Through a collaboration with the Youth Orchestra Los Angeles at Heart of Los Angeles (YOLA at HOLA) program, a partnership between the LA Phil and HOLA which provides free instruments and musical training to children from the Rampart District of Los Angeles, researchers with the USC Brain and Creativity Institute — led by acclaimed neuroscientists Hanna Damasio and Antonio Damasio – will track how children respond to music from the very onset of their exposure to systematic, high intensity music education.
The Circuitry of Uncertainty
The human brain likes to make predictions about how the world works. Imagine, for example, that you move to a new town. At first, you don’t know where to go for dinner. But after weeks of trying different restaurants, you pick a favorite, a little Thai place that makes the best green curry. Several months later, however, you notice the curry isn’t as spicy and the vegetables seem undercooked. At first you give your favorite place the benefit of the doubt. But after a few more so-so dinners, you suddenly realize that something must have changed—perhaps the owner hired a new chef—and your notion that this is the best place around is no longer valid. So you begin searching for a new favorite restaurant.
Neuroscientists have long been interested in this adaptability, particularly in the moment when an individual discards an old belief and begins to formulate a new one. “You go from being confident in your model of the world to being uncertain and then abandoning the model altogether,” says Alla Karpova, a group leader at the Howard Hughes Medical Institute’s Janelia Farm Research Campus. She and her colleagues wondered what goes on in the brain when this happens. In rats, they found that the rejection of an old belief correlates with abrupt changes in activity in the medial prefrontal cortex, a brain region involved in cognitive functions such as reward anticipation and decision-making. The team’s research is published in the October 5, 2012, issue of Science.
Alpha Waves Close Your Mind for Distraction, but Not Continuously, Research Suggests
Alpha waves were long ignored, but gained interest of brain researchers recently. Electrical activity of groups of brain cells results in brain waves with different amplitudes. The so-called alpha wave, a slow brain wave with a cycle of 100 milliseconds, seems to play a key role in suppressing irrelevant brain activity. The current hypothesis is that this alpha wave is associated with pulses of inhibition (every 100 ms) in the brain.
Mathilde Bonnefond and Ole Jensen (Donders Institute for Brain, Cognition and Behaviour, Radboud University Nijmegen) discovered that when distracting information can be anticipated in time there is an increase of the power of this alpha wave just before the distracter. Furthermore, the brain is able to precisely control the alpha wave so that the pulse of inhibition is maximal when the distracter appears. Indeed, between pulses of inhibition, there is still a window where the brain is excitable.
'It is like briefly opening a door to look what's happening outside. This enables us to detect an unexpected but important or dangerous event. But to avoid to be distracted by completely irrelevant information, it is better if the inhibition is active when a distracter is presented. It could be seen as a mechanism slamming the door of the brain on intruders'. The results are published by the scientific journal Current Biology at October 4.
Brain connectivity predicts reading skills
The growth pattern of long-range connections in the brain predicts how a child’s reading skills will develop, according to research published today in Proceedings of the National Academy of Sciences
Literacy requires the integration of activity in brain areas involved in vision, hearing and language. These areas are distributed throughout the brain, so efficient communication between them is essential for proficient reading.
Jason Yeatman, a neuroscientist at Stanford University in California, and his colleagues studied how the development of reading ability relates to growth in the brain’s white-matter tracts, the bundles of nerve fibres that connect distant regions of the brain.
They tested how the reading skills of 55 children aged between 7 and 12 years old developed over a three-year period. There were big differences in reading ability between the children, and these differences persisted — the children who were weak readers relative to their peers at the beginning of the study were still weak three years later.
The researchers also scanned the brains of 39 of the children at least three times during the same period, to visualize the growth of two major white-matter tracts: the arcuate fasciculus, which conects the brain’s language centres, and the inferior longitudinal fasciculus, which links the language centres with the parts of the brain that process visual information.
Differences in the growth of both tracts could predict the variations in reading ability. Strong readers started off with a weak signal in both tracts on the left side of the brain, which got stronger over the three years. Weaker readers exhibited the opposite pattern.
A new field of developmental neuroscience changes our understanding of the early years of human life
Biological Embedding of Early Social Adversity: From Fruit Flies to Kindergartners, a special volume published in the Proceedings of the National Academy of Sciences (1, 2, 3) and authored largely by researchers of the Canadian Institute for Advanced Research (CIFAR), sets out an emerging new field of the developmental science of childhood adversity.
The implications of the research are far reaching, from new approaches to learning and language acquisition, to new considerations for the health effects of social environments affecting large populations, and policies for early childhood care and education.
"CIFAR’s multidisciplinary and international program in early childhood development is transforming our understanding of how early life experiences affect the development of the brain and in so doing set a lifelong trajectory," says Dr. Alan Bernstein, CIFAR President & CEO. "This research is providing the scientific basis for public policy concerning the critical window to provide the optimal conditions that will enable our children to grow up to be well-adjusted, well-educated and productive individuals."
Moms’ depression affects babies’ language development – but so does anti-depressant drug – research shows
Janet Werker and her colleagues played recordings to babies when they were still in the womb.
Then the University of British Columbia psychologist and her team tested babies’ ability to discriminate between English and French when the infants were just six and 10 months old.
The findings, published Monday, are striking.
Both maternal depression, which affects up to 20 per cent of pregnant women, and treating mothers with a common anti-depressant drug threw off infants’ language development, Werker and her colleagues at the University of British Columbia and Harvard University report in the U.S. Proceedings of the National Academy of Sciences.
Babies of depressed mothers were slow to reach language development “milestones,” they report. And babies of mothers taking antidepressants known as serotonin reuptake inhibitors (SRIs) reached milestones months early, they report.