Wednesday, September 28, 2011
Why do we dream? It’s a question dream analysts and sleep researchers have been studying for years. Now new research suggests that some dreams may actually result from the brain’s effort to keep learning, even as we sleep.
In a study led by researchers at Beth Israel Deaconess Medical Center in Boston, 99 volunteers trained for an hour on a virtual maze, trying to find their way through the complicated, three-dimensional puzzle as quickly as possible. Then half the volunteers were allowed to sleep for 90 minutes. The other half stayed awake, reading or relaxing. During the resting period, the subjects were interrupted or awakened and asked to describe their thoughts or dreams.
After the resting period, the participants were asked to again tackle the maze. Those who hadn’t napped showed no improvement or did even worse after the break. Nappers who were rested but didn’t report any maze-related dreams did better but showed only marginal improvement.
However, four nappers who reported dreaming about the maze showed a startling improvement, cutting their completion time in half. The difference in scores before and after sleeping was 10 times higher for the maze dreamers than those who hadn’t dreamed about the task, according to the findings published Thursday in the journal Current Biology.
Even though the number of dreamers was small, the researchers noted that the gap in learning between the dreamers and nondreamers was so wide that the finding was highly statistically significant.
Notably, the dreamers had all performed poorly on the test prior to dreaming about it. That suggests that struggling with a task might be the trigger that prompts the sleeping brain to focus on the subject and work on getting better, explained the lead author, Robert Stickgold, a cognitive neuroscientist at Harvard Medical School.
“It’s almost as if your brain is rummaging through everything that happened today and deciding that you’re not done with it,” Dr. Stickgold said. “The things that really grip you, the ones you decide at an emotional level are really important, those are the ones you dream about. The things you’re obsessed with are the ones that your brain forces you to continue to process.”
The study subjects who dreamed about the maze didn’t dream about trying to complete it over and over. Instead, they simply dreamed about it in a variety of ways. One person said he dreamed about the music that played along with the task. Another dreamed about seeing people along checkpoints in the maze and remembering a bat cave he had once toured. Another dreamed of searching for something in a maze. The lesson may be that dreams don’t necessarily have to make sense or be obvious to the awake mind in order to have a learning benefit.
“It might be that sleep is the time when the brain is tuned to find those types of association you wouldn’t notice during waking,” Dr. Stickgold said. “It does this by focusing on weak associations. If that’s the case, the dreams you have in REM sleep might be so bizarre for exactly the same reasons. It’s not that the dreams make no sense. They make wacky sense.”
More study is needed to fully understand the power of dreams in learning. The researchers are planning a new study that “spiffs up” the maze tests using colors and images in a way that most likely will trigger an increase in dreaming among the study participants.
Whether someone can ultimately harness the power of dreaming to improve learning is an open question, but Dr. Stickgold does have a suggestion for students or others trying to master a task or study subject.
“If you’re a student and you want to do better on the test, you might need to dream about it,” Dr. Stickgold said. “The question is, ‘How do I get myself to dream about it?’ The answer is to get excited about it. That seems to be what you dream about.”
By TARA PARKER-POPE
Sunday, September 18, 2011
The Japanese monkey, Macaca fuscata, had been observed in the wild for a period of over 30 years.
In 1952, on the island of Koshima, scientists were providing monkeys with sweet potatoes dropped in the sand. The monkeys liked the taste of the raw sweet potatoes, but they found the dirt unpleasant.
An 18-month-old female named Imo found she could solve the problem by washing the potatoes in a nearby stream. She taught this trick to her mother. Her playmates also learned this new way and they taught their mothers too.
This cultural innovation was gradually picked up by various monkeys before the eyes of the scientists.
Between 1952 and 1958 all the young monkeys learned to wash the sandy sweet potatoes to make them more palatable.
Only the adults who imitated their children learned this social improvement. Other adults kept eating the dirty sweet potatoes.
Then something startling took place. In the autumn of 1958, a certain number of Koshima monkeys were washing sweet potatoes -- the exact number is not known.
Let us suppose that when the sun rose one morning there were 99 monkeys on Koshima Island who had learned to wash their sweet potatoes.
Let's further suppose that later that morning, the hundredth monkey learned to wash potatoes.
THEN IT HAPPENED!
By that evening almost everyone in the tribe was washing sweet potatoes before eating them.
The added energy of this hundredth monkey somehow created an ideological breakthrough!
A most surprising thing observed by these scientists was that the habit of washing sweet potatoes then jumped over the sea --
Colonies of monkeys on other islands and the mainland troop of monkeys at Takasakiyama began washing their sweet potatoes.
Thus, when a certain critical number achieves an awareness, this new awareness may be communicated from mind to mind.
Although the exact number may vary, this Hundredth Monkey Phenomenon means that when only a limited number of people know of a new way, it may remain the conscious property of these people.
But there is a point at which if only one more person tunes-in to a new awareness, a field is strengthened so that this awareness is picked up by almost everyone!
by Ken Keyes
Wednesday, September 7, 2011
People who volunteer may live longer than those who don't, as long as their reasons for volunteering are to help others rather than themselves, suggests new research published by the American Psychological Association.
This was the first time research has shown volunteers' motives can have a significant impact on life span. Volunteers lived longer than people who didn't volunteer if they reported altruistic values or a desire for social connections as the main reasons for wanting to volunteer, according to the study, published online in the APA journal Health Psychology. People who said they volunteered for their own personal satisfaction had the same mortality rate four years later as people who did not volunteer at all, according to the study.
"This could mean that people who volunteer with other people as their main motivation may be buffered from potential stressors associated with volunteering, such as time constraints and lack of pay," said the study's lead author, Sara Konrath, PhD, of the University of Michigan.
Researchers examined data from the Wisconsin Longitudinal Study, which has followed a random sample of 10,317 Wisconsin high school students from their graduation in 1957 until the present. The sample is 51.6 percent female, with an average age of 69.16 years in 2008.
In 2004, respondents reported whether they had volunteered within the past 10 years and how regularly. They reported their reasons for volunteering (or the reasons they would volunteer, for those who had not done so) by answering 10 questions. Some motives were more oriented toward others (e.g., "I feel it is important to help others," or "Volunteering is an important activity to the people I know best") and some that were more self-oriented (e.g., "Volunteering is a good escape from my own troubles," or "Volunteering makes me feel better about myself").
The researchers also considered the respondents' physical health, socioeconomic status, marital status, health risk factors (i.e., smoking, body mass index and alcohol use), mental health and social support. Much of this information was collected in 1992, 12 years before the respondents were asked about their volunteering experience. The researchers then determined how many of the respondents were still alive in 2008.
Overall, 4.3 percent of 2,384 non-volunteers were deceased four years later, which was similar to the proportion of deceased volunteers who reported more self-oriented motives for volunteering (4 percent). However, only 1.6 percent of those volunteers whose motivations were more focused on others were dead four years later. This effect remained significant even when controlling for all the variables. Additionally, respondents who listed social connection or altruistic values as their predominant motive were more likely to be alive compared with non-volunteers.
"It is reasonable for people to volunteer in part because of benefits to the self; however, our research implies that, ironically, should these benefits to the self become the main motive for volunteering, they may not see those benefits," said the paper's co-author, Andrea Fuhrel-Forbis, MA.
Source: American Psychological Association (APA)