Why Does Pregnancy Last 9 Months? The Cognitive Link

Babies are lovely but altogether helpless creatures.
Wouldn't it be better if tiny humans were born able to walk, like horses, or generally were readier for the rigors of the world, like, say, chimps?
Among primates, human have the least developed brains at birth, at least when compared to adult human brains. If humans were born as far along on cognitive and neurological scales as rough and ready chimps are, though, human pregnancy would have to last at least twice as long. Eighteen months in the womb, anyone?
The prevailing explanation for why pregnancy doesn't last that long boils down to something called the "obstetrical dilemma." Humans walk upright. And the size and shape of our pelvises are constrained by our bipedal way of getting around in the world. If they got much bigger, mothers wouldn't walk as well. So babies' brains could only get so big and still fit through the birth canal, the conventional wisdom holds.
Now researchers at the University of Rhode Island, Harvard and the University of California, Berkeley, are questioning whether the theory is right. Instead of mechanical limits dictating how big a baby's head can get, they propose it's really about how much energy Mom can spare for the developing fetus.
"Mothers gestate a baby as long as they can metabolically," Holly Dunsworth, an assistant professor of anthropology at University of Rhode Island, tells Shots. She's the lead author of a paper advancing the metabolic hypothesis, an alternative explanation that's laid out in a paper being published online by the Proceedings of the National Academy of Sciences. (A link wasn't available as of late Tuesday.)
She and her colleagues concluded that a human baby born at a chimp's level of development would require the average human birth canal to be about 3 centimeters bigger, an increase of a little more than an inch in diameter.
That's feasible, the researchers say. "We show that's within the range of variation now," Dunsworth says. "Those people with wider birth canals aren't walking any worse."
So what is the limiting factor? Apparently, it's how much energy Mom can divert from her own metabolism to the growth and maintenance of a fetus, the researchers say. We humans are able to crank up our metabolism to about twice its normal level and sustain that turbo mode for quite a while.
In fact, pregnant women's metabolism runs at twice the normal level by about the sixth month. By nine months, as the fetus's energy needs increase, the rate is pushing close to 2.1 times normal. And that's pretty much the limit. "Extending gestation even by a month would likely require metabolic investment beyond the mother's capacity," the researchers write.
What happens instead? Mom gives birth, and baby's growth rate slows (compared to its fetal self). Everybody's happy, though it must be said that there's a lot of coddling and many sleepless nights as the needy baby grows into a toddler.
One paper isn't likely to shove the obstetrical dilemma off the scientific stage overnight. But Dunsworth is confident the metabolic argument will hold up.
"Part of the older story is that the birth canal can't get any bigger," she says. "We've shown there's a much better explanation, and we've shown how hard it is to support the old explanation.

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Longer lifespans create new elderly nutrition concepts

As average lifespans push beyond 80 years, demand is growing for products that meet the particular nutritional needs of the elderly such as cognitive performance and bone health. But is it a generation that buys into nutrition-led disease prevention over medical treatment?

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Sleepless Nights May Put The Aging Brain At Risk Of Dementia

As we age, our sleep patterns change. We've all heard the complaints: "I wake up in the middle of the night and can't get back to sleep!"
Some sleep experts estimate that as many as 40 percent of older adults suffer sleeping problems such as sleep apnea and insomnia. Now, researchers have found a link between disrupted sleep and cognitive decline.
Psychiatrist Kristine Yaffe of the University of California, San Francisco, runs a memory disorders clinic and studies people who are at risk of developing dementia and cognitive impairment.
She says many of her older patients "either have difficulty falling asleep, waking up on and off throughout the night, or feeling tired in the day" and have to nap a lot.
Yaffe recently conducted a series of studies evaluating more than 1,300 adults older than 75, initially assessing their sleep patterns and, five years later, their cognitive abilities. She found that those with sleep-disordered breathing or sleep apnea had more than twice the odds of developing dementia years later.
Those who developed disruptions of their circadian rhythm were also at increased risk. So were those who awoke throughout the night, tossing and turning. The findings were presented at the annual conference of the Alzheimer's Association.
It's critical to note that Yaffe's findings show only an "association" between sleep problems and dementia. Far more study is needed to confirm these findings and investigate possible reasons for this connection.
In the meantime, Yaffe says there is something of a silver lining. Older adults can be routinely screened for sleep problems. And, if diagnosed early, treatments can help them sleep better and possibly, down the line, reduce the risk of cognitive decline.
Psychologist Sonia Ancoli-Israel studies sleep and aging at the University of California, San Diego. Ancoli-Israel points to a variety of techniques to help people literally relearn how to go to sleep.
"We want to take a person who has negative associations with the bed — 'Oh, my God, I know I'm not going to be able to sleep' — and turn them around so that they look at the bed and they go 'Ah, sleep,' " she says.
One of the most effective strategies is to actually restrict the amount of time people sleep, starting with very little time — say, five hours — and slowly adding 15-minute increments until the recommended eight hours is reached. It's a slow process, says Ancoli-Israel, taking up to one month. But "it's very, very effective and lasts for years," she says.
Then, there's "stimulus control," in which, as she puts it, "you're not allowed to do anything in bed but sleep — sleep and sex, that's it."
"You can't pay bills in bed, you don't take your computer or your iPhone or iPad to bed, you don't watch TV in bed, you don't read in bed."
If you don't fall asleep in 20 minutes, get out of bed and do something relaxing. "Don't watch a suspenseful movie or read a suspenseful book," she says. "Watch something a little more boring, read something a little more boring, so that when you get sleepy, you're willing to set it down and go to bed."
As for the clock, get rid of it. "The first thing you do when you wake up at night, you look at the clock," Ancoli-Israel says. "And in order to look at the clock, you have to lift your head, open your eyes, but, more important, you have to take yourself from transitional sleep to full awakening to comprehend that its 1:10 in the morning and you want to be asleep." Full awakening, of course, makes it difficult to get back to sleep.
If you need the alarm, cover the clock, she says, or put it under the bed. You'll still hear it go off.
Now, there's another sleep difficulty faced by older adults. Natural circadian rhythms change. Sleep is controlled in part by our core body temperature, which drops at night when we get sleepy and rises in the morning, and that's when we wake up.
These patterns change throughout our lives. Teenagers' body temperature drops late in the evening, so they don't get tired till around midnight and don't naturally wake up till late morning, causing many a parent to complain that their teen is sleeping the day away. In fact, they're simply following their biological clock.
For older adults, it's the opposite. Their body temperature drops really early in the evening, around 8 p.m., and rises really early in the morning, around 4 a.m. If your lifestyle allows it, Ancoli-Israel says it's just fine to go to bed early and get up at 4 a.m.
But for many people, evening social events take precedence. In that case, Ancoli-Israel suggests light. "Light is the strongest cue our body has to know when to go to sleep and when to get up. Lots of light exposure during the day helps us have a strong biological clock," she says.
And the best source of light is the sun. Ancoli-Israel says a late afternoon or early evening walk, when the sun is still out, is best. That delays the circadian rhythm and helps people stay alert later in the evening and sleep longer in the morning.
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Benefits to Early Intervention in Addressing Brain Abnormalities

Preemptive cognitive training -- an early intervention to address neuropsychiatric deficiencies -- can help the brain function normally later in life, a team of researchers has found through a series of experiments on laboratory rats. Their findings, which appear in the latest issue of the journal Neuron, hold promise for addressing a range of brain impairments in humans, including schizophrenia.

The study was conducted by researchers at New York University's Center for Neural Science, the State University of New York (SUNY) Downstate Medical Center, NYU Langone Medical Center, and the Nathan S. Kline Institute for Psychiatric Research.
Researchers have aimed to address human neuropsychiatric impairments, such as schizophrenia, through mental training -- for example, executive function exercises that teach patients to focus their attention and selectively recall important information. Historically, these methods, collectively titled cognitive remediation, have been of limited value because they have been applied to patients whose conditions are too advanced to address.
However, early intervention, in principle, is a viable approach to treatment. This is because of two facts. One, our brains continue to develop and grow up until the age of about 20. Two, experience can have the powerful effect of tuning neural circuits. Taken together, it may be possible to use mental training to harness the young brain's developmental potential to compensate for abnormal neural circuits.
"This means you have a window to intervene prior to a neural system manifesting functional abnormality and becoming unchangeable," explained André Fenton, a professor at NYU's Center for Neural Science and one of the study's co-authors.
Fenton, who is also an associate professor of physiology and pharmacology at SUNY Downstate, added, "If you can detect an abnormality in the brain early enough, you can redirect the trajectory of development and train the younger brain to solve problems that will confront the adult brain."
But a question that has vexed researchers is what kind of training can yield dividends? This matter was the focus of the Neuron study.
The research team conducted its study on laboratory rats at two different stages of life -- at adolescence, or 35 days old, which is the human equivalent of 13 years of age, and as young adults, or 60 days old, which is the human equivalent of just over 20 years, which is the typical onset of schizophrenia symptoms.
Through a series of experiments, the researchers examined the behavior and brain physiology of rats with normally functioning brains and those whose brains had been impaired by lesions, which model the effects of schizophrenia.
In the initial experiment, they used both normal rats and those whose brains had been impaired by lesions, so-called neonatal ventral hippocampus lesion (NVHL) rats, to model impaired cognitive control, one of the core executive function deficits in schizophrenia and other types of mental illness. The rats had to learn to properly navigate a small disk-shaped carousel in order to avoid stepping in an area that would result in a mild electric shock. On the rotating carousel, the rats were given two types of spatial cues -- those that were stationary and necessary to use in order to avoid the area in which they'd receive the electric shock and those that were rotating and irrelevant to this avoidance. The test was designed to mimic the executive function challenges faced by those with schizophrenia -- the inability to distinguish relevant and irrelevant information.
They first tested 60-day old rats. While the normal rats quickly learned to differentiate relevant from irrelevant cues, thereby avoiding the shock zone, the NVHL rats had difficulty doing so. However, with enough training or repetition, the adult NVHL rats eventually learned to avoid the shock zone, but they were again impaired if the task was changed so they had to avoid shock in a new part of the carousel. This experiment mimicked what is often seen with human schizophrenia patients -- that cognitive remediation can improve cognition, but not generally. Improvements are typically limited to particular training tasks, which makes cognitive remediation of limited clinical utility.
In the next experiment, the researchers tested whether preemptive cognitive training, if it occurred early enough in life, would be beneficial in adulthood by diminishing the adult cognitive control impairment. They also made sure to evaluate whether the early cognitive remediation for a single task can help the adult NVHL rats complete other tasks instead of the benefits being limited to mastering the training task.
To test these matters, the researchers gave control and NVHL rats two kinds of experiences when they were adolescents -- at 35 days old. Half the rats in each group received the training to use relevant and ignore irrelevant information to avoid shock in the rotating carousel. As adolescents, the NVHL rats were not impaired; they learned as well as the control group did. The other half of the rats was put on the carousel for the same amount of time, but they were never shocked and so not given an explicit cognitive challenge.
When the NVHL rats were 60 days old, the researchers gave all of them a variety of tasks beginning with a test in a T-shaped maze. The rats first had to learn to go to the left, rather than the right, in order to avoid a mild electric shock. All the rats initially performed well as there was no need for cognitive control. But when the shock was switched to the left, it required cognitive control to ignore the now irrelevant memories of going left. The results showed that the NVHL rats without the early cognitive training were impaired to switch to running to the newly safe portion of the maze. In contrast, all the other rats, including the NVHL rats that had been subject to preemptive cognitive training, switched more successfully than the NVHL rats that had no such training. The same pattern of results was seen in subsequent tests using the carousel task, confirming that the preemptive cognitive training in adolescence was generally beneficial into adulthood, overcoming the cognitively debilitating effects of the persistent brain damage that the NVHL rats sustained.
Not only did preemptive training in adolescence prevent the adult deficits in cognitive control, but when the researchers investigated electrical brain function they observed that the preemptive cognitive training had also corrected how the damaged brain was operating. The researchers recorded the oscillatory electrical activity in different parts of the brain and found that in normal rats that were doing the carousel task, the electrical fluctuations were strongly synchronized between the left and right hippocampi, a part of the brain that is crucial to memory and navigating space. Similarly, in the NVHL rats with preemptive cognitive training in adolescence, neural synchrony in the left and right hippocampi was as strong as the control rats during the control task. These findings indicate that the early cognitive intervention also allowed the brain to function normally during the cognitive challenge, despite the enduring brain damage.
"Our findings show that if you focus the young brain on gaining a certain kind of experience, then we can train it to solve certain types of problems that will confront the adult brain," explained Fenton. "But this must be done at a time when the brain is flexible in order to carve out pathways to gain competencies of a normal brain."
The study's other co-authors were: Heekyung Lee and Hsin-Yi Kao of SUNY Downstate Medical Center; Dino Dvorak of SUNY Downstate Medical Center and the Polytechnic Institute of NYU; Áine Duffy of the Nathan S. Kline Institute for Psychiatric Research; and Helen Scharfman of NYU Langone Medical Center.
The study was supported by a grant from the National Institute of Mental Health, part of the National Institutes of Health.

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Cognitive Rehab Takes A Promising New Direction For The Aging

Studies have shown that declines in temporal information processing (TIP), the rate at which auditory information is processed, underlies the progressive loss of function across several cognitive systems in elderly people. This includes problem solving, new learning, thinking, attention, memory, perception, motor control and concept formation.

However, in a study published in the current issue of Restorative Neurology and Neuroscience, researchers have found that elderly individuals who receiving temporal training improved their cognitive areas and also the rate at which they processed auditory information.

Lead researcher, Elzbieta Szelag, Professor, Head of Laboratory of Neuropsychology, Nencki Institute of Experimental Biology, and Warsaw School of Social Sciences and Humanities, Warsaw, Poland, explained:

Our study showed for the first time significant benefits of temporal training on broad aspects of cognitive function in the elderly. The results were long-lasting, with effects confirmed 18 months after the training."

The team randomly assigned 30 elderly individuals (aged 65-75 years) to one of three groups:
  • One group received temporal training using Fast ForWord Language (FFW), a program involving several computer games designed to enhance memory, attention, and sequencing abilities.
  • One group was assigned to non-temporal training by playing common computer games.
  • One group, the control group, received no training.
The researchers performed a number of tests on all participants prior to training in order to measure their cognitive functioning. Two tests evaluated TIP by measuring sequencing abilities, specifically, at which inter-stimulus-interval participants were able to identify the order or two stimuli presented in rapid sequence.

In addition, the team evaluated three aspects of attention including: the ability to pay attention to multiple processed (divided attention), the ability to sustain attention over a longer time period (vigilance), and the ability to maintain a high level of attention in anticipation of a test stimulus (alertness).

In order to evaluate short term memory the team conducted tests assessing working memory span, the ability to match complex patterns, and the ability to recognize a pattern seen earlier.

Participants assigned to the temporal training group trained for 1 hour per day, 4 days per week, for a total of 8 weeks. These participants started with exercises from the basic module of FFW until they reached 100% complete for each exercise, they then moved onto an intermediate program, and then an advanced program.

For the same time period, participants assigned to the non-temporal training group played computer games, such as Solitaire or Internet games, such as Mahjong. Participants assigned to the control group received no training but were tested before and after the 8 week period.

At the start of the study there were no significant differences in cognitive functioning among the three groups. However, after training the team found that temporal information processing improved among those assigned to the temporal training group. 

In addition, there were improvements in some aspects of attention and short-term memory in this group. In the non-temporal training group, attentional and memory resources scores remained at the pre-training levels, while only the second measure of temporal information processing improved. There were no significant changes in the control group.

Participants assigned to the temporal training group were tested again after 18 months and the team found that the positive effects remained stable. According to the researchers, TIP, matching complex patterns, divided attention, and working memory span remained at a similar level as in the post-training evaluation. However, vigilance of attention declined.

Professor Szelag and Dr Skolimowska, said: "Although FFW does not train other cognitive functions directly, attention and short-term memory resources were necessary to perform the training tasks correctly. To succeed in the FFW games, the temporal skills had to be accompanied by efficient basic cognitive processes."

"These results show a new impact of temporal training on age-related cognitive decline in the senior population. Moreover, they foster a greater understanding of the relationships between timing and cognition, and they show new possibilities for the application of temporal training."

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The smartest 1 percent: Do Americans value intelligence?

We hear a lot about the richest 1 percent in America, but a Duke University researcher says we should be focusing on the smartest 1 percent.
"Many of the people who are transforming society, advancing knowledge, and inventing modern culture are in the top 1 percent in intellectual ability, wrote Jonathan Wai, research scientist at Duke's Talent Identification Program. "Yet ironically, America undervalues math and spatial skills--it is socially acceptable to be bad at math."
On The Daily Circuit Thursday, Wai said the United States needs to put more funding in gifted and talented programs for students to help nurture their abilities.
"If you look at the federal education budget, funding for gifted students is .02 percent of that entire budget," he said. "So, in terms of investing in our gifted students for public education, it just isn't there... We're basically not funding programs for gifted students and we're not investing in the future of America."
This attitude toward subjects such as science and math continues into adulthood, Wai said.
"Today, if you go out to a meal with a friend or something like that and you can't calculate the tip correctly, your friend probably will laugh with you about it," he said. "If you say 'I can't actually read,' people will laugh at you and be in horror about that... Today in America, it's OK to be bad at math... As a culture and society, that's not a good thing because we need to value math."
As a country, devaluing the education of the "scary smart" could lead to long-term economic challenges, Wai said.
From Wai's Psychology Today piece:
A longitudinal study that I worked on as a graduate student has demonstrated that intellectually talented students in the top 1 percent of ability (the super smart) earn doctorate-level degrees (for example, an M.D., J.D., or Ph.D.) at about 25 times the rate of the general population, and that students in the top .01 percent (the scary smart) earn doctorates at about 50 times the base rate. This Study of Mathematically Precocious Youth (SMPY), led by David Lubinski and Camilla Benbow of Vanderbilt University, found that not only is the number of doctorates earned a function of ability but also that income, number of publications, patents, and even likelihood of tenure at a top university significantly increase as IQ increases.
An average person scores 100 on an IQ test using the Stanford-Binet IQ scale. A score of 137 to 160 is considered the top 1 percent to .01 percent of all scorers.
Frank Lawlis, director of psychological testing for American Mensa, also joined the discussion on The Daily Circuit. While Lawlis said that funding gifted and talented programming for the country's smartest is important, he also stressed the need for fostering their social adjustment too.
"These high IQ kids really do have a tougher time socially because they are in the minority," he said. "They often have difficulties with social skills because they are so smart. Their humor is different, their social relationships are different and they obviously get very involved with abstract ideas that don't particularly agree with their friends and their peers. I would support the notion that we need to give more money in terms of helping these kids adjust to their world."
On Facebook, Clint Buhs brought up the stigma he has encountered.
"There's a social stigma with being labeled intelligent in this country, demonstrated by the often negative perception of Mensa as an organization of snobs," he said. "I'm a member, but I'm almost never comfortable mentioning it to others."

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Cognitive Decline in Alzheimer’s Slows in Advanced Age

The greatest risk factor for Alzheimer's disease (AD) is advancing age. By age 85, the likelihood of developing the dreaded neurological disorder is roughly 50 percent. But researchers at the University of California, San Diego School of Medicine say AD hits hardest among the "younger elderly" -- people in their 60s and 70s -- who show faster rates of brain tissue loss and cognitive decline than AD patients 80 years and older.

The findings, reported online in the August 2, 2012 issue of the journalPLoS One, have profound implications for both diagnosing AD -- which currently afflicts an estimated 5.6 million Americans, a number projected to triple by 2050 -- and efforts to find new treatments. There is no cure for AD and existing therapies do not slow or stop disease progression.
"One of the key features for the clinical determination of AD is its relentless progressive course," said Dominic Holland, PhD, a researcher at the Department of Neurosciences at UC San Diego and the study's first author. "Patients typically show marked deterioration year after year. If older patients are not showing the same deterioration from one year to the next, doctors may be hesitant to diagnose AD, and thus these patients may not receive appropriate care, which can be very important for their quality of life."
Holland and colleagues used imaging and biomarker data from participants in the Alzheimer's Disease Neuroimaging Initiative, a multi-institution effort coordinated at UC San Diego. They examined 723 people, ages 65 to 90 years, who were categorized as either cognitively normal, with mild cognitive impairment (an intermediate stage between normal, age-related cognitive decline and dementia) or suffering from full-blown AD.
"We found that younger elderly show higher rates of cognitive decline and faster rates of tissue loss in brain regions that are vulnerable during the early stages of AD," said Holland. "Additionally cerebrospinal fluid biomarker levels indicate a greater disease burden in younger than in older individuals."
Holland said it's not clear why AD is more aggressive among younger elderly.
"It may be that patients who show onset of dementia at an older age, and are declining slowly, have been declining at that rate for a long time," said co-author Linda McEvoy, PhD, associate professor of radiology. "But because of cognitive reserve or other still-unknown factors that provide 'resistance' against brain damage, clinical symptoms do not manifest till later age."
Another possibility, according to Holland, is that older patients may be suffering from mixed dementia -- a combination of AD pathology and other neurological conditions. These patients might withstand the effects of AD until other adverse factors, such as brain lesions caused by cerebrovascular disease, take hold. At the moment, AD can only be diagnosed definitively by an autopsy. "So we do not yet know the underlying neuropathology of participants in this study," Holland said.

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Olympic Sports Have Positive Effect on the Brain

Olympic sports have always represented power, strength, endurance, quickness, balance and more, but recent research has shown that the brain can also benefit.

Researchers from the Mayo Clinic have stated that exercise of any kind makes the heart pump faster - which, in turn, may lower a person's risk of developingdementia and cognitive decline.

The Mayo Clinic team also said that aerobic exercise can help heighten moods - making individuals happier and less stressed. Two of the most popular Olympic sports among people watching the games on TV and athletes all over the world are swimming and running. Swimming is lighter on the joints, but both are effective aerobic sports.

Other sports that provide powerful aerobic exercise are:

  • basketball
  • cycling
  • handball
  • hockey
  • race walking
  • tennis
Other sports featured in the Olympics can have positive benefits on brain function, such as:
  • Rowing
  • Canoeing
  • Fencing
  • Tae-kwon-do
  • Badminton
  • Ping-pong (Table Tennis)
In order to play ping-pong, tae-kwon-do, fencing and badminton - hand-eye coordination, agility and attention to detail are all necessary. However, it is the movement which is required to play these sports which help to boost the brain to work at its full potential.

Cardiovascular workouts, such as canoing and rowing fast in rough waters result in benefits for the brain, as well.

Rodolfo Savica, M.D., a neurologist at the Mayo Clinic commented: 

We  know that 30 minutes of aerobic activity of any kind five times per week is associated with a reduced risk of cognitive decline. So it is important to stay active often and as early as you can. If the Olympic games push people to get active we definitely endorse that.

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