“Stop feeding him milk right away – just to be safe” was not what a new mother wanted to hear. The call came several days after Tamara Caspary gave birth to fraternal twins, a boy and a girl. She and husband David Katz were in the period of wonder and panic, both recovering and figuring out how to care for them.
“A nurse called to ask how my son was doing,” says Caspary, a developmental Read more
Despite advances in genomics in recent years, schizophrenia remains one of the most complex challenges of both genetics and neuroscience. The chromosomal abnormality 22q11 deletion syndrome, also known as DiGeorge syndrome, offers a way in, since it is one of the strongest genetic risk factors for schizophrenia.
Out of dozens of genes within the 22q11 deletion, several encode proteins found in mitochondria. A team of Emory scientists, led by cell biologist Victor Faundez, recently analyzed Read more
The researchers examined neurons in the orbitofrontal cortex, a region of the brain thought to be important for â€œlinking reward to hedonic experience.â€ It was known that stimulants such as cocaine can cause the loss of dendritic spines: small protrusions that are critical for communication and interaction between neurons.
â€œTo make an analogy, itâ€™s like a tree losing some of its leaves,â€ Gourley writes. â€œLaurenâ€™s work shows for the first time that if cocaine is given in adolescence, it can cause the loss of dendrite arbors â€“ as if entire branches are being cut from the tree.â€
The mice are exposed to cocaine over the course of five days in early adolescence, and then their behavior is studied in adulthood. This level of cocaine exposure leads to impairments in instrumental task reversal, a test where mice need to change their habits (which chamber they poke their noses into) to continue receiving food pellets.
A new study using brain imaging to study teen behavior indicates that adolescents who engage in dangerous activities have frontal white matter tracts that are more adult in form than their more conservative peers.
The brain goes through a course of maturation during adolescence and does not reach its adult form until the mid-twenties. A long-standing theory of adolescent behavior has assumed that this delayed brain maturation is the cause of impulsive and dangerous decisions in adolescence. The new study, using a new form of brain imaging, calls into question this theory.
In order to better understand the relationship between high risk-taking and the brain’s development, Emory University and Emory School of Medicine neuroscientists used a form of magnetic resonance imaging (MRI) called diffusion tensor imaging (DTI) to measure structural changes in white matter in the brain. The study’s findings are published in the Aug. 26, 2009 PLoS ONE.
“In the past, studies have focused on the pattern of gray matter density from childhood to early adulthood, says Gregory Berns, MD, PhD, principal investigator and professor of Psychiatry and Neuroeconomics at Emory University and director of the Center for Neuropolicy. “With new technology, we were able to develop the first study looking at how development of white matter relates to activities in the real world.”
Gray matter is the part of the brain made up of neurons, while white matter connects neurons to each other. As the brain matures, white matter becomes denser and more organized. Gray matter and white matter follow different trajectories. Both are important for understanding brain function.
Berns suggests that doing adult-like activities requires sophisticated skills.
“Society is a lot different now than it was 100 years ago when teens were expected to go to work and raise a family,” says Berns. “Now, adolescents aren’t expected to act like adults until they are in their twenties, when they have finished their education and found a career. Listen to Berns discuss the changing definition of adulthood.