Shannon, a 14-year-old who lives in Massachusetts, has amblyopia, a condition sometimes referred to as “lazy eye.”
You can’t tell by looking at her, though. Unlike some amblyopic patients, whose eyes visibly wander, Shannon simply has extremely poor eyesight.
Patients’ best hope for correcting amblyopia is before they turn about 8 years old. Those who don’t get treatment early enough—or for whom treatment doesn’t work—usually end up living with the problem forever.
Shannon is one of those people. Her entire life, she’s worn glasses with a thin non-prescription lens on one side, and a thick corrective lens on the other. As a toddler, her parents tried to make her wear therapeutic eye patches, but she would fling them off.
A few months ago, Shannon enrolled in a clinical study at Boston Children’s Hospital for which she’s taking donepezil, a drug that’s typically used to treat Alzheimer’s. Donepezil is a cholinesterase inhibitor, meaning it increases the amount of acetylcholine circulating around nerve endings. It’s been shown to improve memory function in some patients with dementia.
But of course, Shannon doesn’t have memory problems. Her team of doctors is instead using the donepezil to encourage her brain to learn new skills as quickly and nimbly as an infant’s would. Shannon’s vision has improved markedly over the past four months, her mother told me by phone. Continue reading “Brain fountain of youth”
In a brain that people love to describe as “awash with chemicals,” one chemical always seems to stand out, writes Bethany Brookshire in Slate.com:
“Dopamine: the molecule behind all our most sinful behaviors and secret cravings.Dopamine is love. Dopamine is lust. Dopamine is adultery. Dopamine is motivation. Dopamine is attention. Dopamine is feminism. Dopamine is addiction.
“Dopamine is the one neurotransmitter that everyone seems to know about. Vaughn Bell once called it the Kim Kardashian of molecules, but I don’t think that’s fair to dopamine. Suffice it to say, dopamine’s big. And every week or so, you’ll see a new article come out all about dopamine.
“So is dopamine your cupcake addiction? Your gambling? Your alcoholism? Your sex life? The reality is dopamine has something to do with all of these. But it isnone of them. Dopamine is a chemical in your body. That’s all. But that doesn’t make it simple.
“What is dopamine? Dopamine is one of the chemical signals that pass information from one neuron to the next in the tiny spaces between them. When it is released from the first neuron, it floats into the space (the synapse) between the two neurons, and it bumps against receptors for it on the other side that then send a signal down the receiving neuron. That sounds very simple, but when you scale it up from a single pair of neurons to the vast networks in your brain, it quickly becomes complex. The effects of dopamine release depend on where it’s coming from, where the receiving neurons are going and what type of neurons they are, what receptors are binding the dopamine (there are five known types), and what role both the releasing and receiving neurons are playing.
“And dopamine is busy! It’s involved in many different important pathways. But when most people talk about dopamine, particularly when they talk about motivation, addiction, attention, or lust, they are talking about the dopamine pathway known as the mesolimbic pathway, which starts with cells in the ventral tegmental area, buried deep in the middle of the brain, which send their projections out to places like the nucleus accumbens and the cortex. Increases in dopamine release in the nucleus accumbens occur in response to sex, drugs, androck and roll. And dopamine signaling in this area is changed during the course of drug addiction. All abused drugs, from alcohol to cocaine to heroin, increase dopamine in this area in one way or another, and many people like to describe a spike in dopamine as “motivation” or “pleasure.” But that’s not quite it. Really, dopamine is signaling feedback for predicted rewards. If you, say, have learned to associate a cue (like a crack pipe) with a hit of crack, you will start getting increases in dopamine in the nucleus accumbens in response to the sight of the pipe, as your brain predicts the reward. But if you then don’t get your hit, well, then dopamine can decrease, and that’s not a good feeling. So you’d think that maybe dopamine predicts reward. But again, it gets more complex. For example, dopamine can increase in the nucleus accumbens in people with post-traumatic stress disorder when they are experiencing heightened vigilance and paranoia. So you might say, in this brain area at least, dopamine isn’t addiction or reward or fear. Instead, it’s what we call salience. Salience is more than attention: It’s a sign of something that needs to be paid attention to, something that stands out. This may be part of the mesolimbic role in attention deficit hyperactivity disorder and also a part of its role in addiction.”
Every now and then everyone has trouble sleeping. And then there are those of us who always have the problem.
No wonder the sleep medication industry now accounts for $1.7-billion in spending each year.
Todays Wall Street Journal discusses “A new sleep drug by Merck & Co. is expected to gain U.S. approval in the coming months, even as its main competitor is coming under growing scrutiny by regulators and doctors for sometimes-dangerous side effects. The new drug, known as suvorexant, will affect a different part of the brain than a generation of older medicines such as zolpidem, known as Ambien, which depresses brain activity. The hope is that suvorexant will cause fewer side effects than its older counterparts.
“An estimated 25% or more Americans face a bout of insomnia in a given year, and at least 1 in 10 suffers the chronic form of the disorder, routinely facing sleepless nights, according to the Centers for Disease Control and Prevention.
“There’s a need for more drugs,” said Russell Rosenberg, chairman of the National Sleep Foundation. Current drugs don’t work for everyone, and a push to lower doses amid safety concerns has led to patients “coming in and saying it’s not working as well,” said Dr. Rosenberg, a practicing sleep psychologist and director of the Atlanta School of Sleep Medicine and Technology.
“New sleep drugs may be facing a higher approval bar, amid rising concern that Ambien and similar drugs cause side effects such as risky bouts of sleepwalking and next-day drowsiness, which can impair driving. The U.S. Food and Drug Administration advised doctors to reduce doses of Ambien for women, and added new warnings to its labeling earlier this year.”
A large study suggests that people with serious attention deficit hyperactivity disorder (ADHD) are less likely to commit crimes when taking medication. It is widely known within psychiatry that ADHD symptoms can include difficulties with impulse control, which in some cases can lead to law breaking