Does melatonin do anything at all? Placebo effect, perhaps?


The U.S. Department of Health and Human Services released information today about research on melatonin supplements. The research was conducted at the University of Alberta for the U.S. National Center for Complementary and Alternative medicine. U of A researchers did a comprehensive review of all studies on the use of melatonin supplements to treat sleep disorders.

Click here to read the synopsis of what they found. Not looking so good for melatonin, me thinks!


Dopamine, Fruit Flies, Masochism, and Lethargy


According to this arstechnica article fruit flies lacking (or with extremely low levels of) dopamine suffer from extreme lethargy, and a type of masochism!

Flies that apparently lack dopamine signaling manage to live just as long as their peers. They do, however, end up turning into lethargic masochists. [...]

However, they’re nowhere close to normal. Compared to their normal peers, they were very lethargic, moving relatively little through the course of their normal lives, and not expending the effort to move out of the path of a mild electric current. They spent a lot of their time in the fly equivalent of sleep, even during daylight hours, when they are normally active. Despite the lethargy, however, caffeine was still able to give them a kick start, suggesting that there’s an intact activity control that is simply not getting the sorts of cues it needs without dopamine around.

The same sorts of issues showed up when feeding and visual activity were tested. The flies that lacked dopamine ate only about a third as much as their normal peers and weren’t interested in sugar water even after having been starved. They were still able to respond to sugar and eat, however, which suggests that the animals’ brains still have a feeding capacity that ends up going unused without dopamine. The flies also had normal vision and could use it for spatial orientation, but would no longer move towards light (a phenomenon called phototaxis).

The weirdest effect, however, came when the flies were tested for learned aversion, in which an electric shock is associated with a particular odor. Instead of learning to avoid the shock, however, the dopamine-deficient Drosophila ended up being attracted to the odor, hence the authors’ use of the term “masochistic” to describe the flies’ behavior. (via.)


Electrical Field Surrounding the Brain Serves as a Brain Feedback Loop


A new study published online July 15 in Neuron suggests that the brain’s electric field is not a passive by-product of its neural activity, as scientists once thought. The field may actively help regulate how the brain functions, especially during deep sleep. [...]

In the study, Yale University neurobiologists David McCormick and Flavio Fröhlich surrounded a still-living slice of ferret brain tissue with an electric field that mimicked the field an intact ferret brain produces during slow-wave sleep. The applied field amplified and synchronized the existing neural activity in the brain slice. These results indicate that the electric field generated by the brain facilitates the same neural firing that created the field in the first place, just as the cloud of enthusiasm that envelops a cheering crowd at a sports stadium encourages the crowd to keep cheering. In other words, the brain’s electric field is not a by-product; it is a feedback loop. (via.)


Kleine-Levin Syndrome: Sleep 10 days at a time? You might have it.


“I was hallucinating and after that I don’t remember anything. All of a sudden it just went blank and I just slept for 10 days. I woke up and I was fine again.” [...]

“I was hallucinating and after that I don’t remember anything. All of a sudden it just went blank and I just slept for 10 days. I woke up and I was fine again.” [...]

Louisa is unusual as KLS usually affects teenage boys, who can also exhibit hypersexuality and inappropriate behaviour.

As well as excessive sleeping, symptoms include behaviour changes, irritability, feeling in a dream-like state and binge eating, symptoms that can be mistaken for normal teenage behaviour. [...]

The change in behaviour before and during a sleep episode is one of the most upsetting things for Louisa’s parents, who take it in turns to remain with her. Doctors have told the family it’s crucial to wake Louisa once a day to feed her and get her to the bathroom.

But Lottie admits it can take a while to get her to come round. “I’ve tried before to literally force her to wake up but she just starts swearing and gets so agitated and aggressive.” [...]

Many sufferers have abnormalities in their temporal lobe, the area of the brain involved in behaviour and memory. A scan of Louisa’s brain function revealed she does have abnormalities in her frontal lobe but there are no signs that this has affected her behaviour or memory. (via.)


Circaedian Rhythm & Depression: Light at night alters hippocampus development


Researchers found that female Siberian hamsters exposed to dim light every night for eight weeks showed significant changes in a part of the brain called the hippocampus.

This is the first time researchers have found that light at night, by itself, may be linked to changes in the hippocampus.

These alterations may be a key reason why the researchers also found that the hamsters exposed to dim light at night showed more depressive symptoms when compared to hamsters in a standard light-dark cycle.

“Even dim light at night is sufficient to provoke depressive-like behaviors in hamsters, which may be explained by the changes we saw in their brains after eight weeks of exposure,” said Tracy Bedrosian, co-author of the study and doctoral student in neuroscience at Ohio State University. [...]

The results are significant because the night-time light used in the study was not bright: 5 lux, or the equivalent of having a television on in a darkened room, said Randy Nelson, co-author of the study and professor of neuroscience and psychology at Ohio State. (via.)


Lack of sleep increases risk of suicidal ideation — in teens


Earlier bedtimes may help protect adolescents against depression and suicidal thoughts – Results show that adolescents with parental set bedtimes of midnight or later were 24 percent more likely to suffer from depression (odds ratio = 1.24) and 20 percent more likely to have suicidal ideation (OR=1.20) than adolescents with parental set bedtimes of 10 p.m. or earlier. This association was appreciably attenuated by self-reported sleep duration and the perception of getting enough sleep