2. ABO isn’t the only blood grouping system, however. There are currently 33 systems recognized by the International Society of Blood Transfusion, with monikers like Lutheran, Duffy, Hh/Bombay and Ok.
3. Blood type refers to different molecules on the surface of red blood cells. A mismatch of these molecules between donor and recipient can trigger a fatal immune reaction after a blood transfusion, as the recipient’s body attacks the outsider blood.
4. But not all blood types matter for all transfusions. Some variants are very rare, or exist only in certain ethnic groups, so the danger of getting a mismatch is, for most people, low.
5. The Junior blood type was formally classified just two years ago when researchers pinpointed the molecule responsible for it. The vast majority of people are Junior positive, but more than 50,000 Japanese are Junior negative. For them, a mismatch can cause a dangerous reaction.
6. Blood types aren’t unique to humans. Dogs have more than a dozen, for example.
Young adults who smoked marijuana every day for three years during their teen years have an oddly shaped hippocampus and performed poorly on long-term memory tasks, according to a new study published in Hippocampus this week.
A team led by Northwestern’s Matthew Smith used MRI to map the brains of 97 participants: 44 healthy controls, 10 subjects with a history of marijuana use disorder, 28 schizophrenia patients with no history of substance use disorders, and 15 schizophrenia patients with a marijuana use disorder. Participants with past cannabis use disorder were in their early twenties during the study and had stopped smoking pot for two years; they all started using marijuana daily when they were between 16 and 17 years old for about three years.
All of the recruits took a narrative memory test designed to assess their ability to encode, store, and recall details from stories. “The memory processes that appear to be affected by cannabis are ones that we use every day to solve common problems and to sustain our relationships with friends and family,” study co-author John Csernansky of Northwesternexplains in a news release. Previous work have linked adolescent cannabis use with poor short-term and working memory, as well as the abnormal shape of sub-cortex structures. The hippocampus, on the other hand, plays a key role in long-term (or episodic) memory—the ability to remember life events.
photo credit: Experiences in real-time. Rafael-castillo, CC BY
Rates of substance use are higher in people with mental health problems compared to the general population and particularly in people with bipolar disorder, with cannabis the street drug most frequently used. Estimates suggest that up to 64% of this group have tried cannabis at least once in their lives, against about 30% of those without the disorder, despite only being about 2% of the overall population.
Specific reasons for the high levels of cannabis use in bipolar disorder are not yet fully understood. Retrospective studies (using case histories and qualitative interviews) suggest that individuals see cannabis as sometimes useful for managing symptoms of mania and depression. However, a number of large scale research studies have found that cannabis use is associated with significantly more manic and depressive episodes.
The Daily Experience
photo credit: Kl Petro, via Shutterstock.
The ability to control what happens in one’s dreams is an endearing prospect, so much so that there are pages of information online which supposedly help individuals achieve this curious state, which is known as lucid dreaming. Despite being a well-recognized phenomenon, we still know very little about it, nor why some people seem to experience it more frequently than others.
Now, a new study by scientists at the Max Planck Institute has offered some novel insight into the subject with the finding that a particular brain region known to be involved in self-reflection is larger in lucid dreamers. According to the researchers, this could mean that lucid dreamers are better at self-reflecting during wakefulness.
“Our results indicate that self-reflection in everyday life is more pronounced in persons who can easily control their dreams,” lead author Elisa Filevich said in a news release.
“No pain, no gain!” “You’ll never bulk up without supplements.” “Crunches are the key to six-pack abs!” It seems there are more questions and half-truths in the market about healthy exercise than there are clear, definitive facts—but the exercise industry is a multi-billion dollar business in the United States alone, built partially on selling gadgets and DVDs with incredible claims to people desperate to lose weight or look attractive. Meanwhile, good workout plans and simple truths lurk in the background waiting for their time to shine. All of this results in a ton of misinformation about exercise in general, and while the reality is different for everyone, we’re taking some of those commonly held exercise myths to task, and we have science to back us up. Let’s get started.
We’ve tackled food myths, more food myths, brain myths, and even body myths. This time it’s time to take a look at exercise myths, and we enlisted the help of Dr. Brian Parr, Associate Professor in the Department of Exercise and Sports Science at the University of South Carolina Aiken, to help us out. Here’s what we learned.