amygdala
Creative Minds: Seeing Memories in a New Light
Steve Ramirez/Joshua Sariñana
Whether it’s lacing up for a morning run, eating blueberry scones, or cheering on the New England Patriots, Steve Ramirez loves life and just about everything in it. As an undergraduate at Boston University, this joie de vivre actually made Ramirez anxious about choosing just one major. A serendipitous conversation helped him realize that all of the amazing man-made stuff in our world has a common source: the human brain.
So, Ramirez decided to pursue neuroscience and began exploring the nature of memory. Employing optogenetics (using light to control brain cells) in mice, he tagged specific neurons that housed fear-inducing memories, making the neurons light sensitive and amenable to being switched on at will.
In groundbreaking studies that earned him a spot in Forbes 2015 “30 Under 30” list, Ramirez showed that it’s possible to reactivate memories experimentally in a new context, recasting them in either a more negative or positive behavior-changing light [1–3]. Now, with support from a 2016 NIH Director’s Early Independence Award, Ramirez, who runs his own lab at Boston University, will explore whether activating good memories holds promise for alleviating chronic stress and psychiatric disease.
Tags: 2016 NIH Director’s Early Independence Award, amygdala, anxiety, behavior, brain, cerebral cortex, chronic stress, depression, El Salvador, fear, hippocampus, memory, mental illness, mice, neurons, neuroscience, optogenetics, post-traumatic stress disorder, psychiatric disorders, social phobia
Creative Minds: Helping More Kids Beat Anxiety Disorders
Dylan Gee
While earning her Ph.D. in clinical psychology, Dylan Gee often encountered children and adolescents battling phobias, panic attacks, and other anxiety disorders. Most overcame them with the help of psychotherapy. But not all of the kids did, and Gee spent many an hour brainstorming about how to help her tougher cases, often to find that nothing worked.
What Gee noticed was that so many of the interventions she pondered were based on studies in adults. Little was actually known about the dramatic changes that a child’s developing brain undergoes and their implications for coping under stress. Gee, an assistant professor at Yale University, New Haven, CT, decided to dedicate her research career to bridging the gap between basic neuroscience and clinical interventions to treat children and adolescents with persistent anxiety and stress-related disorders.
Tags: 2015 NIH Director’s Early Independence Award, adolescents, amygdala, anxiety, anxiety disorders, behavior, brain, brain development, brain imaging, child health, children, clinical psychology, cognition, conditioning, fear, hippocampus, memory, mental health, MRI, neuroscience, phobia, prefrontal cortex, psychiatry, psychotherapy, safety signals, sensory cues, stress
Brain Imaging: Tackling Chronic Traumatic Encephalopathy
Caption: Left to right, brain PET scans of healthy control; former NFL player with suspected chronic traumatic encephalopathy (CTE); and person with Alzheimer’s disease (AD). Areas with highest levels of abnormal tau protein appear red/yellow; medium, green; and lowest, blue.
Credit: Adapted from Barrio et al., PNAS
If you follow the National Football League (NFL), you may have heard some former players describe their struggles with a type of traumatic brain injury called chronic traumatic encephalopathy (CTE). Known to be associated with repeated, hard blows to the head, this neurodegenerative disorder can diminish the ability to think critically, slow motor skills, and lead to volatile, even suicidal, mood swings. What’s doubly frustrating to both patients and physicians is that CTE has only been possible to diagnose conclusively after death (via autopsy) because it’s indistinguishable from many other brain conditions with current imaging methods.
But help might be starting to move out of the backfield toward the goal line of more accurate diagnosis. In findings published in the journal PNAS [1], NIH-supported scientists from the University of California, Los Angeles (UCLA) and the University of Chicago report they’ve made some progress toward imaging CTE in living people. Following up on their preliminary work published in 2013 [2], the researchers used a specially developed radioactive tracer that lights up a neural protein, called tau, known to deposit in certain areas of the brain in individuals with CTE. They used this approach on PET scans of the brains of 14 former NFL players suspected of having CTE, generating maps of tau distribution throughout various regions of the brain.
Tags: Alzheimer’s disease, amygdala, brain, cerebral cortex, chronic traumatic encephalopathy, concussion, contact sports, CTE, football, head injuries, imaging, midbrain, National Football League, neurodegenerative disorders, PET scan, tau protein, Traumatic Brain Injury
Anxiety Reduction: Exploring the Role of Cannabinoid Receptors
Caption: Cannabinoid receptor 1 (green) in the mouse brain. All cell nuclei appear blue.
Credit: Margaret Davis, National Institute on Alcohol Abuse and Alcoholism, NIH
Relief of anxiety and stress is one of the most common reasons that people give for using marijuana [1]. But the scientific evidence is rather sparse about whether there’s a biological explanation for that effect.
More than a decade ago, researchers set out to explore the link between marijuana and anxiety reduction, but the results of their experiments were inconclusive [2]. Recently, a team led by NIH-funded researchers at Vanderbilt University Medical Center in Nashville decided to tackle the question again, this time using more sensitive tools that have just become available in recent years.
Tags: amygdala, anxiety, CB1, COX-2, cyclooxygenase-2, endocannabinoids, marijuana, stress, type 1 cannabinoid receptors
