การ ค้นพบนี้ บางทีอาจจะเป็นเหตุผลอธิบาย ว่า ทำไมผู้ที่ดูมีท่าทางเป็นผู้ใหญ่ที่น่านับถือบางคนยังคงแสดงความโมโหโกรธา ออกมา หรือตีหน้ายักษ์ไม่พูดไม่จาเมื่อไม่ได้ดังใจอยู่
การที่พบว่า ส่วนของสมองส่วนสำคัญกับการ คบค้ากับคนอื่น ต้องใช้เวลาหลายสิบปีกว่าจะเจริญ เต็มที่นั้น ยังอาจเป็นสาเหตุที่เหตุใดบางคนถึงได้เคอะเขิน เมื่อเข้าสังคม แม้วัยจะล่วงเลยความเป็นวัยรุ่นไปแล้ว
นักประสาทวิทยาศาสตร์ ซาราห์ เจย์น แบล็กมอร์ กล่าวว่า "เราเชื่อกันมาก่อน แม้แต่เมื่อ 10 ปีมาแล้วนี้ว่า สมองของเราหยุดพัฒนาลงตั้งแต่ต้นวัยเด็ก แต่ บัดนี้เรารู้แล้วว่ามันไม่ถูก ที่จริงแล้วสมองเกือบทุกส่วน ยังคงพัฒนาอยู่เป็นเวลาหลายสิบปี และส่วนที่ใช้เวลาพัฒนายืดเยื้อที่สุด ได้แก่ ส่วนหน้าของสมองกลีบหน้าผาก ซึ่งเป็นส่วนที่ใช้ในการตัดสินใจวางแผน และห้ามใจในการประพฤติอันเป็นที่รังเกียจของสังคม ตลอดจนการเห็นอกเห็นใจและเข้าใจในผู้อื่น".
ที่มา: ไทยรัฐฉบับพิมพ์ วันพุธที่ 23 กุมภาพันธ์ 2554
Brain only fully ‘matures’ in middle age, claims neuroscientist. You might think that you become fully matur when you turn 21 but new research suggests that your brain does not stop developing until your late 40s. Scientists used to believe that your brain stopped physically evolving in early childhood but new research has shown that keeps changing well into middle age. Brain scans have shown that prefrontal cortex – the area just behind your forehead – continues to change shape in your 30s and 40s. The discovery is particularly significant as the prefrontal cortex is a key area of the brain and is often thought said to be key to what makes us human.It is said to be involved with decision making, social interaction
and many other personality traits. Professor Sarah-Jayne Blakemore, a neuroscientist at University College London, revealed the new thinking at the British Neuroscience Christmas symposium in London. She said: “Until about 10 years ago we pretty much assumed that the human brain stopped developing in early childhood. “But we now understand from brain imaging that that is far from the truth and that many human brains keep on developing for many decades.”The area of the brain that goes through the most protracted development is the prefrontal cortex right at the front of the brain.”It is the part of the brain that is involved in high cognitive function such as decision making, planning and social behaviour. It is also to do with understanding other people.”It starts develop in early childhood, is reorganised in late adolescence and continues developing well into the 30s and 40s.”It is the part of the brain that makes us human.” - Blakemore Lab; The Developmental Group at the UCL Institute of Cognitive Neuroscience focuses on the development of mentalising, emotions, action understanding and executive function during adolescence. A second focus of our research is on social cognitive deficits in autism spectrum disorders. Our research involves a variety of behavioural (psychophysics, eye-tracking, motion capture)
and neuroimaging (MRI, fMRI and MEG) methods. We are based at the UCL Institute of Cognitive Neuroscience in Queen Square, London, UK. Group Leader: Prof Sarah-Jayne Blakemore Institute of Cognitive Neuroscience University College London. Current Research and Interest; Social cognitive development during adolescence. Social cognitive processes (action understanding, mentalising, emotion processing) in the normal brain and in people with autism.
http://goodnews.ws/2010/12/26/brain-develops-till-the-age-of-40-you-are-not-as-adult-as-you-think/
The Brain Starts to Change at Age 40
If you’re middle aged, there’s a good reason why you can’t beat your child at games like “Memory” and “Concentration.” Scientists report that after age 40, brain tissue shows genetic changes that may contribute to the aging process, including cognitive decline.Researchers at Children’s Hospital in Boston and at Harvard Medical School report a genetic signature revealed in post mortem tissues of individuals between 26 and 106 years old. They looked at tissue from the prefrontal region of the brain, the locus of higher level functions such as long-term planning and executive function.
Bruce Yankner, lead author of the study, says aging brains show significant differences in the behavior of several groups of genes that are important for brain function and that may contribute to the aging process. One group of the genes plays a role in what researchers call synaptic plasticity—the ability of the brain to make new connections so critical to learning and memory.
It may be that DNA damage in the brain is reversible. --Bruce Yankner, Harvard Medical School
Another group of genes, involved in processes such as responses to stresses and defense against damaging oxidants such as free radicals, are turned on in the aging brain. The researchers found that regions of particular genes are quite vulnerable to DNA damage in the aging brain.
“These regions appear to be quite vulnerable to DNA damage—they are chemically sensitive, and they are not repaired easily,” Yankner says. The findings appear this week as an advance online publication in Nature.
The research team performed a statistical analysis to 11,000 genes for the study, and compared the rates of change over time. The changes in genes of individuals younger than 40 years were quite similar, and the genes of the oldest individuals were also similar. However, the individuals between ages 40 and 73—the middle years—aged at strikingly different rates, with some gene patterns resembling those of the young group, while others had gene patterns more like those of the older group.
Once they zeroed in on the groups of genes, the researchers conducted laboratory tests in which they exposed brain cells to agents such as free radicals and environmental toxins. The results mimic the changes seen in the tissue of aging brains.
On the bright side, when the researchers duplicated the scenario in the lab, and genetically manipulated the cells to produce proteins to repair the damage, the function of the damaged genes was restored, and more copies were made.
“It may be that DNA damage, once it occurs in the brain, is reversible,” Yankner says.
Once the damage is reversed, it might be possible to extend the duration of cognitive function, or to delay the onset of age-related diseases such as Alzheimer’s disease or Parkinson’s. This will be a goal of future research.
“There is certainly evidence that DNA damage can underlie a large part of the aging process in humans,” Yankner says. “My feeling is that the process of maintaining the integrity of the genome is going to be very important in understanding the aging process. Whether it explains the entire spectrum of the aging process, or a part of it, remains to be seen.”
Lu, T. et al. Gene regulation and DNA damage in the aging human brain. Published online in Nature (June 9, 2004).
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