The Color Blind Advantage

I used to think I had Ted Williams-caliber vision (a doctor said that, and it was memorable for a 10-yr old aspiring baseball player). When dreams of baseball stardom started to seem less likely, I began to think I’d make a good pilot. Though I’ve long since chosen a different direction, I still took pride in having a top-notch visual system.

And then I discovered at the age of 28 that I’m colorblind. How did that go undetected for so long? Well, it’s not that I can’t detect colors – I can differentiate and name them well enough – but when given a color blindness test like the one below, I fail miserably.

Can you read the number in this circle?

For most people, the number “74″ jumps off the page, distinct and obvious – but not for those who are color blind. I see a “21″, and someone with more severe color blindness won’t see any numbers.

Color blindness is most often due to missing 1 or more of the 3 different types of cells that detect colors (aka “photoreceptors”) found in a normal eye. Each photoreceptor is tuned to respond to a different wavelength of light, and your brain can interpret their responses by combining the information from each type of photoreceptor, ideally leading to the perception of a vast array of colors.

I’m likely short on 1 type of photoreceptor making me red-green color blind, but it didn’t take long to uncover a rationale suggesting that colorblindness could be an advantage!

In WWII analysis of aerial photographs, teams that included color-blind people were more successful. Color-blind individuals were able to detect unusual patterns in ways that normal-vision people couldn’t.

And more recently, researchers from the University of Calgary showed that color-blind monkeys are better at hunting insects. The monkey’s without color vision caught more insects, presumably because they could see through the insects’ camouflage. Evolutionary speculators have suggested that a group of hunters that contained at least one person who is color blind would be more successful, and so this trait might continue to be selected for in a portion of the population.

It seems that under some circumstances colors can be distracting and actually detract from our ability to see subtle variations in texture and brightness. While it may still be more desirable to have full color vision, the 10% of males who are color blind do have some consolation: We will never starve for lack of camouflaged insects.

More on color vision

Cell phone use and brain activity Part II

By Lumos Labs Science Associate Paul Li, MS Neuroscience.

This post is a follow-up to our previous post on the role cell phones play in increasing the level of awareness. Recently, a different group of researchers have found evidence that using your cell phone before heading to bed can delay reaching the deep stages of sleep. This effect seems to be caused by radiation emitted by cell phones. As you might know, there are 5 stages of sleep that one normally goes through each night, and proper sleep can help to improve memory processing and consolidation. Although the findings may not come as a surprise to you given the results from the previous study, this is especially informative to teenagers and to others who frequently talk on their cell phone before sleeping. Professor Bengt Arnetz, who led the study, believes that cell phone radiation may activate the brain’s stress system “making people more alert and more focused, and decreasing their ability to wind down and fall asleep”.

Ask the Expert: Introducing Dr. Cynthia Green

Got a question about memory or brain fitness? Cynthia Green, Ph.D., the nationally recognized expert on developing better memory and brain health, is here to help with the new Ask the Expert column.

Dr. Green began the Memory Enhancement Program at the Mount Sinai School of Medicine, where she has been a faculty member since 1990. Her first book, Total Memory Workout: 8 Easy Steps to Maximum Memory Fitness, has already been published in 5 languages due to its general applicability for developing a more effective memory. Now, as president of Memory Arts, she continues to lecture and teach the practical principles of brain health.

Submit your cognitive queries as an email to us or as a comment below. Check back at the Brain Health blog for Dr. Green’s expert responses to the most interesting and frequently asked questions.

[Update: Dr. Green has addressed some of your questions in Brain Health 101.]

Working memory and neurogenesis at the Bay Area Neuroscience Gathering

By Lumos Labs Science Associate Paul Li, MS Neuroscience.

Last Friday afternoon, UCSF held their annual Bay Area Neuroscience Gathering (BANG) where local grad students and neuroscientists showcased their research posters to the Bay Area neuroscience community. Universities included UCSF, UC Davis, UC Berkeley, San Francisco State and Stanford. Lumos Labs presented an investigation into web-based experimentation and cognitive training.

Though not many posters were directly related to brain health, I wanted to report the ones that were of relevance and of possible interest to you:

Wesley Clapp, PhD at UCSF found subjects consolidate information differently in their working memory when they know they will face distractors than without any distractors present. They looked at two electroencephalography (EEG) signals that are associated particularly with memory, attention, and perception: the P100 and the N170 (these are electrical signals from the brain that occur at 100 and 170 milliseconds after the event has happened). Clapp and colleagues found that these latencies are modulated differently depending on if the information presented to the subject is relevant or not. He also showed that the amount subjects pay attention to irrelevant information directly correlates with their impairment in working memory performance. To learn more, see Clapp’s research poster.

Leslie Meltzer, a Ph.D student working with Karl Deisseroth at Stanford is studying the effects of antidepressants in rodent models of depression. Meltzer and colleagues found that the therapeutic effects of antidepressants required the growth of new neurons in the hippocampus, a brain region important for memory formation. This suggests that antidepressants might improve mood by increasing the production of new neurons. During Alzheimer’s disease, neurons in the hippocampus begin to die. Could antidepressants be helpful for fighting off dementia? It’s possible, but there are too many unknowns to have a clear picture. Bear in mind that a combination of mental and physical exercises, the types of food we eat, and social activities we do all matter in shaping the condition of our brain.

Are you smarter than a chimp?

Ayumu, a 7-year old chimp living in a lab at Kyoto University, was in the news the last month for his remarkable cognitive performance. In a test of working memory, Ayumu and 5 other chimpanzees were able to outclass college students. Watch him go at it here.

Have you got what it takes to outsmart a chimp? Pit your wits against Ayumu in the Chimp Game.

Early Biomarker for Alzheimer’s?

By contributing author Paul Li, a neuroscience graduate student at Columbia.

Researchers from Stanford might have found a biological marker for Alzheimer’s disease via a simple blood test. This is exciting news given that it might predict the onset of the disease several years before the symptoms begin. The procedure involves examining 18 key proteins in the blood that are typical in Alzheimer’s patients. Preliminary tests have been 90% accurate at detecting the disease. Dr Susanne Sorensen, of the Alzheimer’s Society, said that “Early diagnosis is essential if we are ever to develop treatments that can change the course or halt the progression of dementia rather than just treat the symptoms.”

Cell phone use and brain activity

By contributing author Paul Li, a neuroscience graduate student at Columbia.
Ever since the advent of cellular phones, horror stories have been circulating on issues about its safety, particularly the effects it has on the human brain. Some have become increasingly worried and resort to using an ear piece whenever they are on the phone. While others, like myself included, make sure that their cell phones are no where close to their heads when sleeping. I’ve met people who become agitated when a cell phone antenna is pointing in their direction. Amongst the public’s concern, I was soon caught up in buying a “Safe Guard,” a round sticker that fits nicely on top of the receiving end of the phone, to reduce Electromagnetic Waves, or so the company claimed.

Although no studies have shown a correlation between cell phone use and brain damage, the International Journal of Neuroscience published a study that found a slower EEG brain wave pattern during cell phone use. This difference in brain activity was subtle – within the normal range – but may reflect a
different state of awareness. In fact, they also discovered that frequent cell phone users performed better in selective attention tasks. It’s possible that talking on the phone in the midst of the bustling world’s distractions requires a level of concentration that effectively works as cognitive training of attention.

Eat your vegetables, do your homework, and play your video games?

By contributing author Paul Li, a neuroscience graduate student at Columbia.

When I was a kid, I was constantly scolded by my mother for spending countless hours on my 1989 Nintendo Entertainment System. She thought reading or playing outside would be more beneficial for me than Duck Hunt or Super Mario Brothers. My mother could have never predicted that recent research would show that video games can sometimes actually be good for your brain!

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