Now I am sure most readers have experienced the situation of the above student lament – when you are studying so long and hard that it feels like your head is going to explode – well maybe it is because you are growing so much new brain mass.
Who knew – learning is good for your brain and increases the gray matter density in your brain.
Draganski et. al., 2006 after having already studied how learning to juggle increased gray matter density (in the young and old: teaching old dogs new tricks) turned to examining German pre-med students studying for their medical exam. The examination is called “Physikum”, which is normally taken after the 2nd year of pre-med undergrad and requires daily studying for 3 months to be ready for the written and oral exam in biology, chemistry, biochemistry, physics, human anatomy, and physiology – gee this sounds very similar to the what North Americans undergo when studying for the Medical College Admission Test (MCAT)).
In the study they took 38 want-to-be-doctors (average age = 24) along with 12 matched (age, sex, and education – this group had not taken a recent exam or currently studying for one) control members and they all undertook a baseline T1 weighted MRI scan of their brains. The first scan was done 3 months prior to the medical school exam (before the start of the intensive studying for the exam) and the 2nd scan performed one or 2 days after the exam. For 23 (out of the 38) medical students a 3rd scan was done 3 months after the exam.
There were no difference between the two groups at baseline levels (as expected). During the second scan after the medical school exam revealed an increase in the gray matter of the parietal cortex (posterior and inferior parietal lobule on both sides of the brain) only in the medical students. This region of the brain is thought to be important for declarative memory, and the transfer of memory into long term stores (which you better do if you want to do well on the exam with that amount of information).
Interestingly, there was also a decrease in one part of the brain – the occipito-parietal lobe (both sides). The authors point out this area is directly adjacent to the area in which they observed an increase in white matter (though they really didn’t go into details about this finding in their result section).
Long term results:
Very intriguing is even 3 months after having stopped studying for the exam (who studies once the test is over – and the students were on a semester break during this time period) the increase in the parietal cortex remained – in contrast to the 3 earlier studies (see here and here) I wrote about with juggling training – in which there was also an increase of the brain’s gray matter in particular regions but this increase went away when the subjects stopped juggling for 3 months.
(and with the music training I wrote about on Monday that also finds an increase in gray matter density with training I have not come across a study were they took musicians that stopped practicing to see what would happen – return to baseline?).
There was also an increase in the hippocampus (an important structure for memory) between the first and third scan – but it was not significant at the time of the 2nd scan (right after the exam), but interestingly became significant 3 months after the students had stopped studying for the exam when they were on a ‘relaxing’ semester break. The authors of the study suggest that the stress of studying might have countered the positive effects of studying since the hippocampus is sensitive to stress overall. And once the exam and stress was over the brain bounced back and was able to structurally change. This overall goes with my general (and common sense) ideas regarding the great possibility of cycling ‘stress’ and relax/relief periods being very benefical for the brain and body (e.g simple exercise, every-other-day fasting, and I could go on forever about this subject but will keep this for another time).
None of the above brain changes were observed in the control group over the same time period – even though they were matched for age, sex and education level – however the control group had taken no exams in the last 6 months and were not studying for any exams at the time of the study.
However, none of the brain changes in the students correlated with their performance on the medical school exam (and overall the students’ average in the study was the same as the average for all 7,043 students who took the test).
Take home messages:
It appears that intense studying, in this case for a medical exam but I am sure this would also be true for university students trying to obtain a very high average, various professional exams (e.g. Law school entry test), graduate students studying for their comprehensives or thesis defense, would undergo similar brain changes. What is interesting is in comparison to the ‘simpler’ task of learning to juggle the brain changes appear longer lasting and even occurring after the studying period (hippocampus).
So yes musical training and learning new tasks like juggling will increase your brain’s gray matter density but so will good old fashion learning.
As my grandfather said, ‘never can have enough learnin’
Many of my friends in the past have trudged through medical school exams (MCAT) and/or undergone a PhD and apparently had the added benefits of increase their gray matter density (assuming this is a good thing). For all of you out there contemplating taking the exam (1/4 of the university population ?) – here I hope is an additional reason for taking up the challenge – increase your brain’s gray matter. Doesn’t matter what mark you get on the test as long as you study hard you will gain and heck you might even make it into medical school (the one think I do know is that it is pretty hard to make it into medical school without taking the test).
So pick up a musical instrument and start playing, or 3 balls and start juggling, or many heavy books and start studying – to a better and bigger brain.
my guess is the difference in long term results between the studying and juggling is amount of time put in. like “massed practice” rehabilitation. and similar to the pro musicians. I would bet that if the jugglers juggled for a greater time each day (maybe not even as long as the studying), they would retain the benefits for longer.
possibly the difference is just a matter of time put in. Maybe the jugglers put only an hour a day (paper didn’t give details – but I would assume the average person wouldn’t put more than an hour in) – while studying for medical exam probably was more than an hour a day (especially combined with normal schooling). Though I am curious if fairly pure motor tasks differ than tasks that require a greater proportion of your brain – though not sure.
I hope I’m not digressing too much… I’m confused, does brain size predict intelligence?
I thought someone or some group(s) already disputed it (maybe from studying Einstein’s brain – his brain was not any bigger than other people, was it?)
But some papers seem to show that brain size does correlate with intelligence, (e.g. ‘Brain size, IQ, and racial-group differences: Evidence from musculoskeletal traits’ by Rushton and Rushton, 2002).
Until I got this figured out, I don’t know what to take from these ‘more studying = bigger grey matter’ studies…
I am not arguing that a bigger brain in more intelligent. I am not sure about the latest data regarding this subject.
What I am suggesting is just like muscles the brain can be ‘exercised’ and at least in some cases ‘grows’ to adapt to the new learning – or so it appears from the papers I discussed. Open to alternative possibilities.
wasn’t Einstein’s brain denser though? more astrocytes I think read someplace long ago.
So if the skull is more flexible, people who study a lot would have heads like the alien-mother’s…COOL!!
Then the really cool guys will be the ones with big heads, not big muscles…
I’ve been studying for my exams and my brain is starting to swell in the cranial cavity, atleast near the parietal lobe area.
So subtracting the ill-effects of environment and normal aging processes, if one was to bet, should one try to excercise the mind or the body to ensure that you can still hold court in the twilight years of your mind? Or both?
yes I heard the same story about Einstein’s brain having more astrocytes (and possibly more astrocytic endfoots) and I was reminded of this information while reading a recent book about Einstein.
yes it is obvious that men and women should be attracted to potential partners with bigger brains (is there anything sexier?)
if you still want to hold court as you age – you should both exercise your brain and body.
Read big Russian novels (e.g. Dostoyevsky) while doing one arm chinups at the gym
Thank you for your sage advice.