Dr Scientific Chick, PhD

Great news! My defense went very well, and I have officially been accepted in the PhD club.

I am currently rediscovering some of life's little pleasures, such as reading non-neuroscience related books, and having free time. Free time! What a concept.

Thank you all for your encouragements in the comments of the previous post, and see you soon for more exciting science news!

And now, a word from your friendly graduate student

This week, I'm skipping the usual science story in favor of something different: a look at the life of a graduate student who will be defending her thesis in a week.

Yup, that's right, the marvelous PhD adventure is already and finally coming to an end. I say "already" because the last 6 years were filled with new friends, interesting courses, exciting science and all the perks that come with being a student (2 words: free transit). I say "finally" because the last 6 years were also filled with too many new beginnings, many frustrations, and a whole lot of stress. Overall, an amazing experience, but like all good things, it must come to an end, and it's time to move on.

That being said, it's not over until it's over. At the end of April, I will stand in a tiny room filled with professors and a few supporters (I'm so very excited that my parents are making the trip to come and encourage me!), summarize the last 6 years of my work in 20 minutes, and then get grilled on everything I know until I wave the white flag of ignorance. So until then, every single one of my days consists of waking up, studying, freaking out when I realize that I don't know anything about anything, then going to bed, and having dreams about my defense. It's a bit of a roller coaster ride, but I've done this before (for my comprehensive exam, the mid-PhD grilling to make sure you're worthy), and I've gotten better at it.

So stay tuned for the next post, in which you will learn if I'm a doctor or not, and regular programming will return shortly. I've been saving an interesting article on what to eat to ward off dementia, and I think you'll want to hear about it.

Magnets make morals moot?

What does it mean to act morally? Is it to cause benefit and not harm? Is it to do what’s right? Who gets to decide what’s right? While philosophers have been debating these questions for millennia, neuroscientists are now joining in the fun. In recent years, researchers have been taking pictures of people’s brains while moral judgments are being made to try to make sense of it all. In a recent article published in PNAS, a team of American researchers tried to find where morality lives in your brain.

The researchers used a technique called transcranial magnetic stimulation (TMS, see picture). In short, it consists of placing magnets near the participant’s head and applying a magnetic field targeted at a specific brain region. The current generated by the magnetic field can pass through the skull and disrupts the targeted brain region. The whole thing is non-invasive and not painful.

Using this technique, the researchers disrupted a region called the right temporoparietal junction while participants were making moral judgments on scenarios like this one:

“Grace and her friend are taking a tour of a chemical plant. When Grace goes over to the coffee machine to pour some coffee, the friend asks for some sugar in hers.”

There are then four potential outcomes, which participants rated on a scale ranging from permissible to forbidden:

1. Grace thinks the powder is sugar, and it is sugar, so everyone stays alive and happy.
2. Grace thinks the powder is sugar, but it’s actually toxic, and the friend dies.
3. Grace thinks the powder is toxic, but it’s just sugar, so Grace’s evil plan is thwarted and the friend lives.
4. Grace thinks the powder is toxic, and it is toxic, and the friend dies.

Some friend Grace is, right?

Anyway, the researchers found that participants who underwent the procedure made similar moral judgments as control participants in all the situations but one: the instance where Grace thinks the powder is toxic but it’s not (#3 above). In this case, participants who had a part of their brain disrupted by TMS thought Grace’s actions were significantly more permissible than control participants. One might say their moral judgment was altered. In fact, almost every single news story that reported on this article suggested that the interpretation of these results meant that TMS to the right temporoparietal junction of the brain leads to altered moral judgments. So that must be where morality resides!

Interestingly, even the researchers do not claim this. In the article, they write: “TMS did not disrupt participant’s ability to make any moral judgement.” Remember, the TMS subjects rated 3 out of 4 outcomes the same as control participants. That means their moral compass is intact. It is also important to note that in the case where TMS participants thought Grace’s actions were more permissible than the control participants, this difference was only of about 15%. So what’s going on? Well, one can judge the morality of an action based on a number of criteria. The easiest criterion is outcome: did the friend live or die? Children under 6 (before the “age of reason”) mostly use this criterion to decide if actions are good or bad. But another criterion (among many others) is intent. Did Grace mean to poison her friend or not? In the situation 3, Grace meant to poison her friend, so if you were to judge morality on intent, it would be forbidden. But the friend lived, so if you judge morality on outcome, it would be permissible. What the authors suggest is that disrupting the right temporoparietal junction reduces how much one cares about intent. Which is different than “reduces one’s morality”.

Of course, like any good study, other interpretations cannot be ruled out. For example, TMS may interfere with other cognitive functions that have nothing to do with morality. Overall, the finding is interesting, but as always, more work needs to be done to get a better grasp of the inner workings of our morality.

Next time you get a tour of a chemical plant, watch your drink...

Reference: Disruption of the right temporoparietal junction with transcanial magnetic stimulation reduces the role of beliefs in moral judgements. (2010) Young, L. et al. Proc Natl Acad Sci USA Mar 29 [Epub ahead of print].