Posts tagged research
Articles and news from the latest research reports.
3D reconstruction of Phineas Gage’s skull, showing the passage of the tamping iron. Read about Gage’s connectome here
Disorders of consciousness: How should clinicians respond to new therapeutic interventions?
August 2, 2012
New tools have confirmed high rates of misdiagnosis of patients with chronic disorders of consciousness, such as the vegetative state. An increasing number of patients’ families wish to use these novel techniques for diagnosis, prognosis, and treatment. An international team of researchers, including Dr. Éric Racine, researcher at the IRCM, analyzed the clinical, social and ethical issues that clinicians are now facing. Their article is published in the August edition of The Lancet Neurology, a renowned journal in the field of clinical neurology.
"Patients with disorders of consciousness have traditionally been regarded as unaware by definition, but findings from recent clinical studies have revealed astounding cases of awareness despite clinical unresponsiveness," explains Dr. Racine, a Montréal neuroethics specialist.
Severe brain injury can leave patients with chronic disorders of consciousness, which are medical conditions that inhibit consciousness. Patients thus have severe motor and cognitive impairments, remain fully dependent on others for all activities of daily living, and have no or very limited means to functionally communicate their thoughts or wishes, depending on their state.
Even with a careful neurological assessment of these types of disorders, some signs of awareness can elude the clinician because the clinical diagnosis relies on the observation of motor signs of awareness, which can be very subtle and fluctuate over time.
New technological developments can now measure brain function both in resting states and in response to simple commands, independent of muscle function, which could help establish a more accurate diagnosis. As a result, diagnostic classifications have been revised and prognostic knowledge is improving. For the first time, therapeutic studies have recently shown the effects of treatment on the improvement of patient responsiveness.
"The medical decision to stop or continue rehabilitation, or to transfer a patient to a long-term care facility can be hard to accept for the family, but one of the most difficult treatment decisions by family members remains whether to continue life-sustaining therapy or to discontinue it and only provide palliative care," says Dr. Racine.
Media coverage of disorders of consciousness has increased and information on the subject is increasingly available to the public. Clinicians such as neurologists, rehabilitation specialists, family doctors, and nurses must answer more requests from patients’ family members for novel diagnostic and therapeutic procedures.
"Clinicians therefore need to be prepared to discuss disorders of consciousness with ethical sensitivity, especially considering that the new procedures remain investigational," adds Dr. Racine. "They must be aware of the level of evidence supporting them and of the unavoidable ethical and social issues involved in responding to requests from patients’ family members."
Provided by Institut de recherches cliniques de Montreal
Source: medicalxpress.com
Coffee May Help Some Parkinson’s Disease Movement Symptoms, Research Suggests
"Studies have shown that people who use caffeine are less likely to develop Parkinson’s disease, but this is one of the first studies in humans to show that caffeine can help with movement symptoms for people who already have the disease," said study author Ronald Postuma, MD, MSc, with McGill University in Montreal and the Research Institute of the McGill University Health Center. Postuma is also a member of the American Academy of Neurology.
Concussions and head impacts may accelerate brain aging
Jul 31, 2012 by Laura Bailey
Concussions and even lesser head impacts may speed up the brain’s natural aging process by causing signaling pathways in the brain to break down more quickly than they would in someone who has never suffered a brain injury or concussion.
The photos compare images of two brains, one with and without head injury. The red areas indicates electrical activity in response to the task researchers asked study participants to perform, and non-injured brains show more red, thus more electrical activity during the task. Image courtesy of Steven Broglio
Researchers from the University of Michigan School of Kinesiology and the U-M Health System looked at college students with and without a history of concussion and found changes in gait, balance and in the brain’s electrical activity, specifically attention and impulse control, said Steven Broglio, assistant professor of kinesiology and director of the Neurotrauma Research Laboratory.
The declines were present in the brain injury group up to six years after injury, though the differences between the study groups were very subtle, and outwardly all of the participants looked and acted the same.
Broglio, who is also affiliated with Michigan NeuroSport, stressed that the studies lay out a hypothesis where concussions and head impacts accelerate the brain’s natural aging process.
The study, “Cognitive decline and aging: The role of concussive and subconcussive impacts,” appears in the July issue of journal Exercise and Sport Sciences Reviews.
"The last thing we want is for people to panic. Just because you’ve had a concussion does not mean your brain will age more quickly or you’ll get Alzheimer’s," Broglio said. "We are only proposing how being hit in the head may lead to these other conditions, but we don’t know how it all goes together just yet."
Broglio stressed that other factors, such as lifestyle choices, smoking, alcohol consumption, physical exercise, family history and whether or not you “exercise” your brain also impact the brain’s aging process. Concussion may only be one small factor.
To begin to understand how concussions might impact brain activity and its signaling pathways, researchers asked the participants to perform certain tasks in front of a computer, and took images of their brains. The brains of the nonconcussed group showed a greater area of electrical activation than the participants with a history of brain injury.
The signaling pathways in our brains are analogous to a five-lane highway. On a new highway, traffic runs smoothly and quickly as all lanes are in top shape. However, during normal aging, the asphalt deteriorates and lanes might become bumpy or even unusable. Traffic slows.
Similarly, our brains start with all pathways clear to transfer electrical signals rapidly. As we age, the brain’s pathways break down and can’t transfer the information as quickly. Concussive and other impacts to the head may result in a ‘pothole’ on the brain’s highway, causing varying degrees of damage and speeding the pathway’s natural deterioration.
"What we don’t know is if you had a single concussion in high school, does that mean you will get dementia at age 50?" Broglio said. "Clinically, we don’t see that. What we think is it will be a dose response.
"So, if you played soccer and sustained some head impacts and maybe one concussion, then you may have a little risk. If you went on and played in college and took more head balls and sustained two more concussions, you’re probably at a little bigger risk. Then if you play professionally for a few years, and take more hits to the head, you increase the risk even more. We believe it’s a cumulative effect."
In the next phase of study, researchers will look at people in their 20s, 40s and 60s who did and did not sustain concussions during high school sports. They hope to learn if there is an increasing effect of concussion as the study subjects age. If interested in participating in the study, email neurotraumalab.umich@gmail.com.
Researchers from the departments of Physical Medicine and Rehabilitation, and Neurology, and the Michigan Alzheimer’s Disease Center also participated in the study.
Source: University of Michigan
Eyes and Attention of Men and Women Meander in Distinctly Different Ways
Dr. Itti’s lab studied 34 participants as they watched videos of people being interviewed. Behind the interview subjects, within the video frame, pedestrians, bicycles and cars passed by — distractions included to pull attention away from the filmed conversation.
While participants watched and listened to the interview, another camera was pointed at participants’ eyes, recording the movement of their pupils as they glanced across the screen.
Researchers discovered the following:
• Men, when focused on the person being interviewed, parked their eyes on the speaker’s mouth. They tended to be most distracted by distinctive movement behind the interview subjects.
• By contrast, women shift their focus between the interview subject’s eyes and body. When they were distracted, it was typically by other people entering the video frame.
Brain development is delayed in attention-deficit/hyperactivity disorder
July 30, 2012
Is attention-deficit/hyperactivity disorder (ADHD) due to a delay in brain development or the result of complete deviation from typical development? In the current issue of Biological Psychiatry, Dr. Philip Shaw and colleagues present evidence for delay based on a study by the National Institutes of Health.
The cerebral cortex is the folded gray tissue that makes up the outermost portion of the brain, covering the brain’s inner structures. This tissue has left and right hemispheres and is divided into lobes. Each lobe performs specific and vitally important functions, including attention, thought, language, and sensory processing.
Two dimensions of this structure are cortical thickness and cortical surface area, both of which mature during childhood as part of the normal developmental process. This group of scientists had previously found that the thickening process is delayed in children diagnosed with ADHD. So in this study, they set out to measure whether surface area development is similarly delayed.
They recruited 234 children with ADHD and 231 typically developing children and scanned each up to 4 times. The first scan was taken at about age 10, and the final scan was around age 17. Using advanced neuroimaging technology, they were able to map the trajectories of surface area development at over 80,000 points across the brain.
They found that the development of the cortical surface is delayed in frontal brain regions in children with ADHD. For example, the typically developing children attained 50% peak area in the right prefrontal cortex at a mean age of 12.7 years, whereas the ADHD children didn’t reach this peak until 14.6 years of age.
"As other components of cortical development are also delayed, this suggests there is a global delay in ADHD in brain regions important for the control of action and attention," said Dr. Shaw, a clinician studying ADHD at the National Institute of Mental Health and first author of this study.
"These data highlight the importance of longitudinal approaches to brain structure," commented Dr. John Krystal, Editor of Biological Psychiatry. "Seeing a lag in brain development, we now need to try to understand the causes of this developmental delay in ADHD."
Dr Shaw agrees, adding that this finding “guides us to search for genes that control the timing of brain development in the disorder, opening up new targets for treatment.”
Additional work expanding these measures into adulthood will also be important. Such data would help determine whether or when a degree of normalization occurs, or if these delays translate into long-lasting cortical deficits.
Provided by Elsevier
Source: medicalxpress.com
When rules change, brain falters
For the human brain, learning a new task when rules change can be a surprisingly difficult process marred by repeated mistakes, according to a new study by Michigan State University psychology researchers.
Imagine traveling to Ireland and suddenly having to drive on the left side of the road. The brain, trained for right-side driving, becomes overburdened trying to suppress the old rules while simultaneously focusing on the new rules, said Hans Schroder, primary researcher on the study.
A better judge of character with oxytocin nasal spray?
In other contexts, oxytocin is already well-known as the “bliss hormone”. The hormone is secreted upon stimulation by touch and is known to result in a feeling of calm and physical relaxation. It is also used to induce labour in childbirth and as an aid for women experiencing difficulties in breastfeeding.
Oxytocin has also been referred to as a “mindreading” hormone. Recent research findings show that there may be some truth to these claims – although the mindreading component may have a more down-to-earth explanation.
Can bacteria fight brain cancer?
The thinking behind an approach that has caused trouble in California.
Last week, the Sacramento Bee reported that two neurosurgeons at the University of California, Davis, had been banned from research on humans after deliberately infecting three terminally ill cancer patients with pathogenic bacteria in an attempt to treat them. All three died, two showing complications from the infection. Nature explores what happened and the science behind it.
“Emotion Detectives” Uncover New Ways to Address Youth Anxiety and Depression
26 July 2012
Emotional problems in childhood are common. Approximately 8 to 22 percent of children suffer from anxiety, often combined with other conditions such as depression. However, most existing therapies are not designed to treat coexisting psychological problems and are therefore not very successful in helping children with complex emotional issues.
To develop a more effective treatment for co-occurring youth anxiety and depression, University of Miami psychologist Jill Ehrenreich-May and her collaborator Emily L. Bilek analyzed the efficacy and feasibility of a novel intervention created by the researchers, called Emotion Detectives Treatment Protocol (EDTP). Preliminary findings show a significant reduction in the severity of anxiety and depression after treatment, as reported by the children and their parents.
“We are very excited about the potential of EDTP,” says Ehrenreich-May, associate professor of psychology in the College of Arts and Sciences at UM and principal investigator of the study. “Not only could the protocol better address the needs of youth with commonly co-occurring disorders and symptoms, it may also provide additional benefits to mental health professionals,” she says. “EDTP offers a more unified approach to treatment that, we hope, will allow for an efficient and cost-effective treatment option for clinicians and clients alike.”
Emotion Detectives Treatment Program is an adaptation of two treatment protocols developed for adults and adolescents, the Unified Protocols. The program implements age-appropriate techniques that deliver education about emotions and how to manage them, strategies for evaluating situations, problem-solving skills, behavior activation (a technique to reduce depression), and parent training.
In the study, 22 children ages 7 to 12 with a principal diagnosis of an anxiety disorder and secondary issues of depression participated in a 15-session weekly group therapy of EDTP. Among participants who completed the protocol (18 out of 22), 14 no longer met criteria for an anxiety disorder at post-treatment. Additionally, among participants who were assigned a depressive disorder before treatment (5 out of 22), only one participant continued to meet such criteria at post-treatment.
Unlike results from previous studies, the presence of depressive symptoms did not predict poorer treatment response. The results also show a high percentage of attendance. The findings imply that EDTP may offer a better treatment option for children experiencing anxiety and depression.
“Previous research has shown that depressive symptoms tend to weaken treatment response for anxiety disorders. We were hopeful that a broader, more generalized approach would better address this common co-occurrence,” says Bilek, doctoral candidate in clinical psychology at UM and co-author of the study. “We were not surprised to find that the EDTP had equivalent outcomes for individuals with and without elevated depressive symptoms, but we were certainly pleased to find that this protocol may address this important issue.”
The study, titled “An Open Trial Investigation of a Transdiagnostic Group Treatment for Children with Anxiety and Depressive Symptoms,” is published online ahead of print in the journal Behavior Therapy.
The team is currently recruiting participants for a randomized controlled trial comparing the EDTP to another group treatment protocol for anxiety disorders. For more information, please contact the study coordinators at www.miami.edu/childanxiety.
Source: ScienceBlog