Posts tagged brain scans
Articles and news from the latest research reports.
Your Brain on Big Bird: Sesame Street Helps to Reveal Patterns of Neural Development
Using brain scans of children and adults watching Sesame Street, cognitive scientists are learning how children’s brains change as they develop intellectual abilities like reading and math.
The novel use of brain imaging during everyday activities like watching TV, say the scientists, opens the door to studying other thought processes in naturalistic settings and may one day help to diagnose and treat learning disabilities.
Scientists are just beginning to use brain imaging to understand how humans process thought during real-life experiences. For example, researchers have compared scans of adults watching an entertaining movie to see if neural responses are similar across different individuals. “But this is the first study to use the method as a tool for understanding development,” says lead author Jessica Cantlon, an assistant professor in brain and cognitive sciences at the University of Rochester.
Eventually, that understanding may help pinpoint the cause when a child experiences difficulties mastering school work. “Psychologists have behavioral tests for trying to get the bottom of learning impairments, but these new imaging studies provide a totally independent source of information about children’s learning based on what’s happening in the brain,” says Cantlon.
The neuroimaging findings are detailed in a new study published Jan. 3 by the Public Library of Science’s open-access journal PLoS Biology, by Cantlon and her former research assistant Rosa Li, now a graduate student at Duke University.
Neuroscience offers a glimpse into the mind - and our future
Hassan Rasouli recently accomplished a remarkable feat: He lifted his thumb in a way that suggests he was making a thumbs-up gesture.
The feat was a remarkable one since doctors at Sunnybrook Health Sciences Centre in Toronto had diagnosed him as being in a persistent vegetative state (PVS), a mysterious condition in which patients appear to be awake but show no clinical signs of conscious awareness.
The condition first came to prominence in 1998 when family members, and then courts and politicians, engaged in a protracted battle over the care of Floridian Terri Schiavo. The matter was finally settled in 2005 when Schiavo, who was in a persistent vegetative state, was removed from life support and died.
Doctors at Sunnybrook similarly wanted to transfer Rasouli to palliative care, but Rasouli’s family refused. The doctors therefore sought a court order, and the Supreme Court of Canada heard arguments in the case on Monday.
The court’s decision might not affect Rasouli since, given his ability to give a thumbs-up gesture, he is no longer considered to be in a persistent vegetative state (PVS). But the case could have a profound impact on the many other patients who have been diagnosed as being in a PVS, as it could answer pressing legal questions about when someone can be removed from life support, and who has the authority to order that such support be discontinued.
The Rasouli case also raises further troubling questions of fact: Was Rasouli’s ability to give a thumbs-up gesture an indication that his condition had improved, or was he never in a persistent vegetative state? Was he, and other people similarly diagnosed, always consciously aware, but, thanks to being trapped in a paralyzed body, unable to express his thoughts?
(Illustration by Bert Dodson)
Brain imaging alone cannot diagnose autism
In a column appearing in the current issue of the journal Nature, McLean Hospital biostatistician Nicholas Lange, ScD, cautions against heralding the use of brain imaging scans to diagnose autism and urges greater focus on conducting large, long-term multicenter studies to identify the biological basis of the disorder.
"Several studies in the past two years have claimed that brain scans can diagnose autism, but this assertion is deeply flawed," said Lange, an associate professor of Psychiatry and Biostatistics at Harvard Medical School. "To diagnose autism reliably, we need to better understand what goes awry in people with the disorder. Until its solid biological basis is found, any attempt to use brain imaging to diagnose autism will be futile."
While cautioning against current use of brain imaging as a diagnostic tool, he is a strong proponent of using this technology to help scientists better understand autism. Through the use of various brain imaging techniques, including functional magnetic resonance imaging (MRI), positron emission tomography (PET), and volumetric MRI, Lange points out that researchers have made important discoveries related to early brain enlargement in the disorder, how those with autism focus during social interaction and the role of serotonin in someone with autism.
"Brain scans have led to these extremely valuable advances, and, with each discovery, we are getting closer to solving the autism pathology puzzle," said Lange. "What individuals with autism and their parents urgently need is for us to carry out large-scale studies that lead us to find reliable, sensitive and specific biological markers of autism with high predictive value that allow clinicians to identify interventions that will improve the lives of people with the disorder."
Autism and autism spectrum disorder (ASD) are terms regularly used to describe a group of complex disorders of brain development. This spectrum characterized, in varying degrees, by difficulties in social interaction, verbal and nonverbal communication, and repetitive behaviors, whose criteria have been revised in the newly proposed Diagnostic and Statistical Manual of Mental Disorders (DSM-5). The prevalence of ASD in the United States has increased 78 percent in the last decade, with the Centers for Disease Control estimating that one in 88 children has ASD.
(Source: eurekalert.org)
