Teenagers cannot concentrate because their brains are undeveloped

Jun 02, 2010 by Lin Edwards report

(PhysOrg.com) -- New research from the UK has found that teenagers and young adults find it hard to concentrate because their brains are more similar to those of much younger children than those of mature adults, with more grey matter but lower efficiency. The findings suggest the brain is not fully developed until people reach their late twenties or even early thirties, which is much later than previously thought.

The researchers, Dr Sarah-Jayne Blakemore and colleagues, from the Institute of at the University College London, used scans to monitor the activity in the brains of 200 volunteers aged between seven and 27 as they tried to run through the alphabet mentally or with letters on a computer screen while simultaneously deciding whether or not the letters contained a curve. At the same time they had to ignore distracting letters without curves.

The results found the human brain continues to develop longer into the teenage years and adulthood than previously believed, with the abilities of the volunteers improving with their age. In the teenagers an unexpectedly high level of activity was observed in the part of the brain known as the prefrontal cortex, which is a region known to be involved in multi-tasking and making decisions. This suggests their brains had to work harder to process the information. The same type of activity was known to occur in the prefrontal cortex in the brains of young children, but was not expected to continue into the teens and beyond.

The researchers said the results indicate the brains of teenagers are working less efficiently than adults’ brains. Dr Blakemore said the part of the brain needed to solve the problem is still developing in the adolescents, and the activity in the indicates they are doing a lot of needless work with "chaotic thought patterns".

Blakemore said the research shows “there is simply too much going on in the brains of ” for them to concentrate on the task at hand. That means resources and energy in the brain are wasted, which has a negative effect on decision-making.

The brain’s consists of the cell bodies and connections that carry messages within the brain. As we age, the amount of grey matter decreases, which Blakemore said means neural transmissions travel more efficiently in adults, and the works more effectively.

The research paper is due to be published today in the Journal of Neuroscience.

Explore further: Research letter examines pacemaker use in patients with cognitive impairment

More information: Iroise Dumontheil, et al., Development of the Selection and Manipulation of Self-Generated Thoughts in Adolescence, The Journal of Neuroscience, June 2, 2010, 30(22):7664-7671; doi:10.1523/JNEUROSCI.1375-10.2010

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User comments : 20

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KronosDeret
2 / 5 (3) Jun 02, 2010
that would definetly explain a lot... :D
Jeswin
1.8 / 5 (4) Jun 02, 2010
Fascinating!
JCincy
1 / 5 (1) Jun 02, 2010

LOL! Was this research necessary?

Next up... babies sometimes cry because they are hungry.
CSharpner
3.8 / 5 (5) Jun 02, 2010
They're making a lot of assumptions. Looking at this as a software issue (thought in a brain is very much like software)... Think of "skills" as hard-coded program logic that's been tested, optimized, retested, and reoptimized. It becomes very efficient and requires fewer CPU cycles (or fewer neurons firing). A task that is completed that's not part of your skill set (or software that hasn't been optimized) takes longer because you don't have that hard wiring, so instead of skipping a lot of steps that a skilled brain (or program) has been optimized out of, an unskilled program (or brain) must analyze much more and do more computations and consider items that a skilled (or optimized) program doesn't need to come up with the same result. Obviously, with age, there are more skills. I'd like them to repeat this test, but with a skill that the current generation of youngsters have that adults generally don't. I wouldn't be surprised to see the opposite results.
Djincs
3.5 / 5 (2) Jun 02, 2010
The older you get, the less is your ability to learn, small children lern to talk without dificulties, for a old person to learn a language at that level is much harder...
Leathersoup
4.5 / 5 (2) Jun 02, 2010
So what's my excuse? :)
Objectivist
1 / 5 (1) Jun 02, 2010
@CSharpner
I agree to your point, but not the level of impact. Most things taught in school are things one does not yet know about, thus there is no hard wiring. Speaking for myself I get bored if I'm studying a subject that I can't place in a broader scale, meaning if I can't understand the purpose of the subject it turns into irrelevant information. If I find a subject interesting and relevant to my perspective of the world I can learn almost every detail about it, and most importantly also when I was younger. Incidentally I can't help thinking about a previous study which showed that as you grow older your brains ability to filter out irrelevant information weakens.

But I still get your point, the brain is very complex and such narrow studies can only provide narrow data and nothing general.
Bloodoflamb
not rated yet Jun 02, 2010
They're making a lot of assumptions. Looking at this as a software issue (thought in a brain is very much like software)... Think of "skills" as hard-coded program logic that's been tested, optimized, retested, and reoptimized.
Cognition in any animal is only SUPERFICIALLY like software. Software is extremely rigid and inflexible. When an error is encountered, it does not self-correct, it just fails to work. If thought worked that way, you wouldn't have anything much more complicated than single celled organisms.
CSharpner
3 / 5 (2) Jun 02, 2010
Bloodoflamb,

I disagree. I'm a software architect with 28 years experience. Though, current, single-threaded software isn't as elegant as the software in biological logic units (brains), they ARE similar... not just similar, but logic processing in a biological logic unit IS software... It's not just "like" software, it IS software. It's a massively parallel hardware system running massively parallel software. But, whether we're talking about crude computer software or the more complex biological software, some things are the same. In particular, they both receive input, process data, and give output. During the processing, they decode the input, analyze it, find relevancy to pre-stored data, categorize, store, make decisions, and output. When code (or thought) is optimized, it takes fewer processing cycles. This is true for manufactured or biological based logic processing.
CSharpner
1 / 5 (1) Jun 02, 2010
Additionally, software is not always rigid and inflexible. neural nets come to mind (which is extremely similar to biological logic processing). Even "regular" software can be extremely flexible. It's just a matter of intention, need, and resources to create the software.
ChiRaven
5 / 5 (1) Jun 02, 2010
What are the implications of this research on how our educational system ought to be structured? If learning takes place most efficiently later in life, why are we concentrating our academic learning experiences so early? On the other hand, there is also research to suggest that maximum creativity (at least in certain technical fields) peaks some time in the twenties ... before this says the optimal brain activity efficiency is reached.

This should be something that our educational researchers take seriously, instead of wasting time with the predigested Pablum thet usually play with.
ChiRaven
not rated yet Jun 02, 2010
And doesn't this seem to contradict research described here http://www.physor...704.html which stated that teenagers tend to underutilize the prefrontal cortex in decision-making?
HealingMindN
3.7 / 5 (3) Jun 02, 2010
They should scan the brains of the BP Stooges.
Arthur_Zombie
1 / 5 (1) Jun 02, 2010
The brain is not hardware that implements an information processing software. This idea is a tired paradigm drawn from the computer as model.

"Biological Logic Units [Brains]" ....?

The influence AI and the information processing wave have on theories in cognitive science will slowly diminish, in place of more fruitful and accurate work (cf. Varela et al, 1991, the embodied mind; Thompson, 2007, Mind in Life).

Welcome to 21st century cognitive science.
HristosGe
3 / 5 (2) Jun 03, 2010
Correct me if I'm wrong, but the main difference between the brain and a software is that brain is creative, it can actually find solutions, while a software simply follows a certain algorithm. Even so, I believe the similarities are quite a lot!
CSharpner
not rated yet Jun 04, 2010
Computer software CAN be creative. There are plenty of products out there that help writers when they get writers block. Additionally, IBM has recently created software modeled on the human brain and runs it on one of their massively parallel supercomputers. To date, their software is about as intelligent as a common cat (I was amazed to read that!) They're about 4% the power of a human brain. Add more and faster hardware and they'll reach human capabilities (emotions, creativity, and all).

The brain is MOST DEFINITELY hardware. Each neuron is a CPU with limited capability. It has multiple inputs with varying signal strength. The timing of the input, which receptors receive the input, and the strength of the input trigger certain output to certain transmitters at certain strengths. These are linked to other neurons with similar capabilities (but different amounts of inputs and different rules (code/logic) to determine output). Billions of these are constantly (continued...)
CSharpner
not rated yet Jun 04, 2010
continued...
Billions of these are constantly engaged in a continuous feedback loop, working together as a massively parallel computer. There are also millions of input lines (nerves from the body (skin, ear, nose, eyes, taste buds, etc...) that are hooked into this giant feedback loop. All of this operating together forms what we call "thought".

Forget "AI". There's just "I". It doesn't matter whether it operates on silicon based hardware or carbon based hardware.

BTW, my nitpick of the week: It's not "a software". It's just "software" (drop the "a").
CarolinaScotsman
not rated yet Jun 05, 2010
I submit that it's not a matter of maturity or immaturity but rather a matter of focus. The young brain is focused on acquiring knowledge and the older brain is focused on applying knowledge. While the brain is never 100% one or the other (both acquisition and application are always present), the emphasis changes over time and continues to shift as long as the person is alive. So that an 80 year old's brain would be more "mature" (ie more application focused) than a forty year old's brain. Each stage of focus serves its own purpose and is relavent to the stage of life of the person.
bottomlesssoul
not rated yet Jun 05, 2010
@JCincy
LOL! Was this research necessary?

Next up... babies sometimes cry because they are hungry.
It might seem obvious to you so it's not for you. The observations and conclusions would really help the teenagers that are being and will be victimized by adults treating them as if they had mature brains, accusing them of having mature brains and punishing accordingly.

Like when an 18.01 year old puts his he who in his 17.99 year old friends woo who and spends the next 35 years in prison for rape.
Amy2010
5 / 5 (1) Jun 06, 2010
Was this study done just on teenage males? We do know males are much slower to mature than girls and that a woman's brain is often more mature than a males thoughout life so my guess is they did not use girls in this study. I have heard that a girl is mature in her mid teens and if a male's brain is not fully developed until people reach their late twenties or even early thirties there are many fewer years for males to be function as adults as they also die several years earlier than women. It would average out to about 40 years for males and 55 to 60 years for women. And they say women are the weaker sex when just the opposite is true.