Tag Archives: neuroscience

Rita Levi-Montalcini

30 Dec

Dr. Rita Levi-Montalcini, 103-year-old neuroscientist and all-around impressive individual, has passed away this weekend. (2012 has been a bad year to be a personal hero of mine, statistically.)

Graduating medical school in 1930s Italy as a Jewish woman, Levi-Montalcini faced unbelievable amounts of adversity from the beginning of her academic career. Nonetheless, she went on to share the 1986 Nobel Prize for Physiology or Medicine with Stanley Cohen for their discovery of nerve growth factor (NGF). NGF is crucial to the survival of many neurons, and is therefore a focus of ongoing research into disorders where cell growth is abnormal, including dementia.

While her loss remains a loss to us all, Levi-Montalcini was also the first Nobel Laureate to reach 100 years of age, and if that’s not the best that can be hoped for in a lifetime, I don’t know what is.

The Guardian has a profile that is well worth a read. The following is my favorite passage:

“Making her own microsurgical and tissue-manipulating equipment – using, among other things, reshaped domestic sewing needles and modified watchmaker’s tweezers — she began her fruitful investigation into normal and abnormal neural development and its mechanisms of control. Discovery of her activities could have resulted in imprisonment or death, but she attracted little interest by buying fertile eggs to investigate the early phases of nerve growth in chick embryos. As a bonus to concealment, many of the experiments could be eaten when they were finished.”

A Sense of Smell

6 Sep

Olfaction is not one of the topics most people look forward to with bated breath when going into a neuroscience course; at least, that hasn’t been my experience. Most people (often myself included) are looking out for the trendier stuff — consciousness, phantom limbs, schizophrenia, hallucinations. But it should come as no surprise that the neuroscience of olfaction, or the sense of smell, is both a hotbed of current research and a fascinating area of study. The 2004 Nobel Prize in Physiology or Medicine was awarded to Linda Buck and Richard Axel for their discovery of the family of genes (about 1,000 genes total) which code for olfactory receptors in humans.

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Why Cells Age

7 Feb

I’m in the middle (er, maybe the first third) of a class on the neurobiology of aging. As such, we’ve covered a few different theories of aging, from the molecular (telomeres!) to the evolutionary (grandparents!). There are about as many overlapping theories of why we age as there are branches and specializations within biology. Aging affects all of us if we’re lucky, and all systems within our bodies, yet we don’t know precisely why it happens at all.

A new paper from scientists at the Salk Institute theorizes that cellular aging may be linked to “extremely long-lived proteins” (ELLPs). Keep in mind that cellular aging is slightly different from aging as a person; some cells throughout your body are constantly aging, dying, and being replaced, no matter what your age is. Other cells are mostly with you from birth until death — neurons are one such group of cells. With some slight, recently-discovered exceptions, there is very little neurogenesis (the birth of new cells in the brain) after childhood.

This new research into ELLPs focuses on the aging of brain cells, which is important, as they are not replaced when they are damaged or die off. Culturally, it’s also important because brain aging is a big deal in our population. I mentioned above that some cells (like skin cells or the lining of the stomach) are being replaced fairly regularly. Another mechanisms that cells use to repair damage is to replace or recycle the proteins that carry out cellular activities.

One important class of protein in brain cells is the transporter protein. The ELLPs in this study form channels that allow ions and other small molecules in and out of the cell past its membrane, which is how neurons signal to each other.

If this type of protein gets worn down or damaged, it is not able to be replaced or recycled, according to this paper. In that case, neurons will have a hard time signaling to each other, and the accumulated damage over many years could lead to problems throughout the brain.

This paper is new and interesting, although it doesn’t provide any easy answers, and definitely requires further study (For instance, the study was done on rats, which are a good model organism, but which also have much shorter lifespans than humans have). It does, however, illustrate one of my favorite differences between physicists, who have variously flavored quarks, and biologists, who have “extremely long-lived proteins.” I don’t know what that says about our respective fields, but it must mean something.

In which I am a stereotypical scientist because my first response is “Neat!”

5 Feb

Apparently there’s been a story making the rounds lately, about a dozen junior high and high school girls in New York with what is being diagnosed as conversion disorder, a psychological disorder that manifests itself in tics and other motor or sensory symptoms, for which you would normally expect a biological (rather than psychological) interpretation. The disorder on display in New York doesn’t appear to be traditionally contagious, or caused by environmental factors. Naturally, this makes people a little nervous.

Being a firm if somewhat facetious believer in House’s definition of “idiopathic” — “from the Latin meaning we’re idiots ’cause we can’t figure out what’s causing it” — I was skeptical. But the school district, department of health, and related agencies have conducted what appears to be a pretty thorough check on all the other possible causes, as seen in this report. Some of the highlights (what, you don’t want to read an 8-page scientific report in your spare time?) follow:

  • The 12 cases have nothing in common save for their school, which has been checked for environmental factors that could have caused the symptoms, and their gender.
  • 1 of the 12 cases had a preexisting diagnosis of Tourette’s syndrome, and 2 other cases had earlier diagnoses of other illnesses associated with tics.
  • The cases have been dispersed and ongoing over the past seven months.
  • The time course of the cases indicates that it was NOT (repeat: was NOT) linked with Gardisil or any other vaccination.
  • Of the 12 cases, 8 were examined by a pediatric neurologist. All 8 of those cases had experienced “significant life stressors.” (This one seems to be the big blinking red lights sign, at least from my point of view.)

Evidence-based Treatment

19 Nov

I read this article the other day on the success of treatment for juveniles in justice populations.  It’s pretty solid, and has to do with a lot of what I worked on at TASC this summer.

Because here’s the deal: we can’t fix everything with science. Yet. (I would argue for that “Yet.” Some people would argue “Ever.” Some people also smoke cigarettes and don’t wear seatbelts and watch American Idol and pronounce it “nuculer.” Only a person standing at the precise intersection of arrogance and ignorance could possibly believe that science will ever stop changing and improving and discovering new things.)

So: We can’t fix everything with science yet, but we can help. A reduction, as per the article, from 15.5% of juvenile offenders (a problematic word, but let’s press on) committing violent felonies to only 4.3% of those who underwent the treatment committing violent felonies isn’t perfect, but it’s not nothing. The fact that the treatment has proven to be effective for as long as I’ve been alive is also pretty promising.

I was, though, a little bemused by the repeated use of the term “evidence-based treatment.” I mean, as opposed to what? I understand that it’s generally just shorthand for “treatments that have been thoroughly studied and are based on scientific premises,” but really, that raises the question: What other kinds of treatments are people trying?  Treatments that have not been thoroughly objectively studied and that are not based on scientific premises? Non-evidence-based treatment?

It’s as simple as this: We have science; use science. The day someone can explain to me why that is complicated will be the day I can truly claim to understand the human brain.

Back to rambling

13 Nov

You know when you haven’t blogged for a month due to a cold that was probably in reality the plague and all of your midterms happening at once and the unwise but totally necessary decision to spend a weekend in Disneyland and then Halloween evening with Neil Gaiman and Amanda Palmer and a couple hundred close friends? And THEN you know when it’s your birthday and your grandparents call you up to sing to you and your grandma chides you for not blogging after she told everyone about your blog?

I mean, sure. I think we all know the feeling.

This semester has been insane. Mostly with the neurobiology. But here’s the thing: I’ve been learning amazing things that I should so totally be telling the world about. Like, for instance, you know the temporal lobe?

Now you do. (It's green.)

Apparently, at least according to one of my professors, it was so named because it corresponds to the temples, where people tend to go gray, denoting the passage of time — hence, temporal. And somehow I’ve gone four years without learning this, or making the connection between temporal lobes and temporal anomalies and Temporal Dominoes. It’s wonderful and ridiculous and makes me feel slightly dense.

Or, did you know that your olfactory bulb (responsible for your sense of smell) has no direct input to your frontal lobe, which is why you can’t reconstruct a smell in your memory the same way you can a face.  (Try it.  When I say “Think of Abraham Lincoln,” you can see Abraham Lincoln in your mind’s eye — or most people can.  When I say “Think of the smell of apple pie,” you can come up with various sensory cues, but you can’t reconstruct it in the same realistic way.  No, you can’t.  Even if you think you can, you can’t.  Trust me.)

Anyway, I’m actually still here and alive and all, and the world is an amazing place, and there is snow and a Soyuz launch in Baikonur tonight, and I am graduating in six months. And that about sums up the past month of my life. Hopefully I’ll have slightly more time to write up real science-y things going into winter break and my final semester.

(Hi Gram and Papa!)

Speak Out With Your Geek Out, Part II: Brains

13 Sep

Let’s get one thing straight: I don’t like zombies, for the same reason I don’t like vampires — because I get distracted trying to piece together a way in which they could make any biological sense, thus ruining any fictional, escapist, or allegorical content of whatever it is I’m looking at.

So, this post is about the other kind of brains: the real kind, the kind that don’t provide sustenance to the undead (somehow) — in short, the cool kind.

There’s a lot to say about the brain, and I have a little bit more knowledge about neuroscience than I do about rocket science. But the #speakgeek concept is all about the joy of loving nerdy things, and there are few topics in neuroscience that induce more nerdy glee than the concept of the brainbow.

Take that, Hubble!

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