AP Biology class blog for discussing current research in Biology

Tag: Brain Plasticity

Clock Change is Actually Great For Your Brain!

November this year, our clocks went back an hour, which accelerated the arrival or darker evenings and seemingly “shorter days”. It doesn’t actually make the days any shorter, in merely just shifted an hour of available daylight from the evening to the morning. Most people take lighter evenings as a priority over lighter mornings, arguments are always made over the benefits for easier travel in lighter evenings from clock changes. However, research suggests that holding onto lighter mornings could give more advantages. Having light in the morning, instead of any other time of the day, leads significant brain-boosting results. In fact, it helps us to function much better.

Early Morning

Credit: Attribution license: Porsche Brosseau


All living animals and plants on Earth revolve their lives around the 24-hour cycle of light and dark. For humans, we desire to sleep during the dark night, and our bodies are honed to environmental light via a biological chain reaction. 

We, humans, detect light intensity by special cells in the retina, then the information is relayed to the internal body clock in the brain, called the suprachiasmatic nucleus. It is in the hypothalamus (which uses the endocrine system to regulate internal body processes), which is linked to hormone secretion, through the pituitary gland. These light messages’ job is to internalize information about light intensity in the surrounding environment.

The chain reaction continues with the brain driving the secretion of the hormone cortisol for a specific time of the day, it is in low levels in the dark and high levels in the light. Cortisol is a very important hormone that has very dramatic effects on the human brain and body. The cortisol is also known as the “Stress hormone” that keeps us healthy through its 24-hour pattern.

The cortisol awakening response(CAR) occurs the first 30 minutes of waking up, it is a strong burst in cortisol secretion. The lighter the mornings, the bigger the CAR. Which directly results in a better functioning brain throughout the day. In an experiment, people who have greater seasonal depression, stress, anxiety and lower arousal exhibited the lowest winter CARs. But when they are exposed to artificial light during their awakenings, their CAR was restored. Thus proving that morning light is the most effective treatment for the winter blues.

Other research has also shown that CAR in the morning is directly linked to better brain plasticity, better goal-setting, decision-making and executive function.

The burst of cortisol secretion in the morning sweeps throughout the entire body where it is recognized by receptors on all body cells. The receptors then generate the biological chain reaction to allow us to function better for the day ahead. A lack of light in the morning can make us feel not functioning fully, and an exposure to light in the morning is extremely beneficial.


Intellectual Growth Spurts? They might just be possible

Photo Taken By Reigh LeBlanc

For many years, educators and researchers have been using the IQ test as the most comprehensive way of measuring a person’s intelligence. They have also upheld that this one-time measurement will be accurate throughout a person’s life; in other words, one’s intellectual capacity does not change over time. However, as it turns out, this logic may not be as infallible as it once seemed.

Back in 2004, Cathy Price and a group of other scientists tested the IQ’s of a number of teens and then took structural images of their brains using an MRI scanner. Four years later, the same experiment was conducted on the same individuals, and on average, the IQ scores were the same. Differences in scores that occurred for some students were simply attributed to him/her having an “off-day.”

What scientists are now increasingly interested in, however,  is the brain data for this group of inconsistent students. The MRI scans for these teens are showing that, as opposed to simply having varying levels of concentration during the two tests, they actually underwent significant changes in the density of grey matter in their brains. Grey matter is a major component of the brain, consisting of neuron cell bodies, glial cells, and capillaries. In the cases of these students, an increase in IQ score (sometimes up to 21 points) was accompanied by an increased density of grey matter in certain key areas of the brain, such as the left motor cortex.

If these results are confirmed by further experimentation, they could have a significant effect on our educational system. Proving that teenagers do, in fact, have a “malleable intellect,” would mean that judging kids based on one-time examinations such as the SAT may not be such a good way to determine their potential.

But don’t get too excited kids. If students’ intelligence can change over time, it is more likely that they would be encouraged to take more standardized tests, since they might perform better after allowing their brains to grow a little. In addition, although the exact causes of these spikes in IQ are unknown, it has been proven that certain mental exercises can cause a growth in grey matter. If grey matter density does parallel intelligence, we will se an increase in the emphasis on these activities in the training of young adults.

For these reasons, in the coming years we will likely see an increase in studies on this subject. If certain exercises or activities are proven to boost an individual’s intelligence, as many scientists are hypothesizing, this could revolutionize the way we that we train our children, both in school and at home.

Which activities do you think will be found to increase a person’s intellectual capacity?

For more information on this particular study, visit

Powered by WordPress & Theme by Anders Norén

Skip to toolbar