This article from Science Daily discusses how the unconscious brain is able to function without the availability of the conscious brain. In one case, a patient survived an accident with brain damage and face blindness. To test her unconscious brain, doctors showed her images of familiar faces, unknown faces, and celebrity faces. They included new celebrities, as well as those who were famous before the patient’s accident.
The patient was not able to recognize the famous faces, however, her brain responded to the celebrities from before her accident. Professor Pegna concludes, “implicit processing might continue to occur despite the presence of an apparent impairment in conscious processing.” As long as a person’s cerebral structures are in a certain order (regarding time), then he will be able to respond to visual stimuli.
I think it is amazing how a person’s memory—from the time of the accident and beyond—may be damaged, but the memories that were established prior to the accident are still in tact. We can see here that just because a person with brain damage may not outwardly communicate visual awareness to doctors does not mean the brain is unresponsive. Ultimately, we can learn how important physiological testing is to learning about the condition of the brain.
Photograph: http://www.molwick.com/en/brain/025-human-brain-structure.html
According to the New York Times, a recent study suggests that the internet and technology have significant effects on human memory. Scientists, led by Betsy Sparrow of Columbia University, conducted experiments testing the effect of technology on human memory. One test had participants type 40 pieces of trivia into a computer. They led half of the participants to believe that the trivia would be saved and the other half to believe that the trivia would be deleted. They found that the participants were a lot more likely to remember the trivia if they thought it would be deleted. Another test examined how computers affect what exactly we remember. The subjects were asked to remember specific facts and which of five folders on the computer they were saved in. The researchers found that the test subjects remembered the folder instead of the fact.
The experiment dives into what is called transactive memory. This theory suggests that people rely on other people and reference materials to store information instead of trying to remember this information themselves. Dr. Sparrow concluded that the Internet has become the number one source for external storage of information.
This article was interesting because technology and the age of the internet has taken over the world. There is no shortage of how and when we can retrieve information. This article raises some significant points. Are we becoming too dependent on technology to store information? Can this, in the long term, affect humans negatively? For all the advantages of the internet and computers, there are still some questions that linger.
PHOTO: http://hplusmagazine.com/sites/default/files/images/articles/mar10/man-inserting-memory-card-in-brain.jpg
What where once thought to be little more than structures to fill the gaps between important neurons, may play a more important role than just that. Recent studies have suggested that these star shaped cells in our brains called astrocytes, are involved in information processing, signal transmission, and help to regulate neurons and synapses. Also they are responsible for long-term memory formation.
Lactate from astrocytes into neurons is what long-term memories are dependent on. When that transfer of lactate in to neurons is blocked in any way, lab rats fail to remember what happened days or weeks ago, with short term memories being unaffected. The way the scientists tested this idea in rats was rather simple. By exposing rats to a single unpleasant experience, particularly a foot shock, they form a lasting memory of where the unpleasant experience occurred and avoid it. Then, when disrupting the lactate transporters on the astrocytes or neurons the rats developed amnesia.
These are important findings that in the future, may help us better understand neurodegenerative diseases such as Parkinson’s or just the memory loss associated with old age. Synaptic function loss between neurons and the astrocytes seem to be the main cause of long-term memory loss. More studies and experiments on the synapses between the neurons and astrocytes may help us form remedies that will help us retain our long-term memories before we lose them.
More than two-thirds of adults in the United States are overweight, and more than one-third are obese, according to government estimates.
According to ScienceDaily, by knocking down the expression of a protein in rat brains known to stimulate eating, Johns Hopkins researchers say they not only reduced the animals' calorie intake and weight, but also transformed their fat into a type that burns off more energy. The finding could lead to better obesity treatments for humans, the scientists report.
"If we could get the human body to turn 'bad fat' into 'good fat' that burns calories instead of storing them, we could add a serious new tool to tackle the obesity epidemic in the United States," says study leader Sheng Bi, M.D., an associate professor of psychiatry and behavioral sciences at the Johns Hopkins University School of Medicine.
The Johns Hopkins study, published in the journal Cell Metabolism, looks at two types of fat made by the body: white and brown adipose tissue. White fat is the typical fat that ends up around your middle and other places, and is the storehouse for the extra calories we eat. White fat cells have a single large droplet of lipid, one of fat's building blocks, such as cholesterol and triglycerides.
Bi and his colleagues designed an experiment to see if suppressing the appetite-stimulating neuropeptide Y (NPY) protein in the dorsomedial hypothalamus of the brain would decrease body fat in rats. Located just above the brain stem, the hypothalamus helps regulate thirst, hunger, body temperature, water balance and blood pressure.
For five weeks, two groups of rats were fed a regular diet, with one group also treated with a virus to inhibit NPY expression and the other left as a control group. At the end of five weeks, the treated group weighed less than the control group, demonstrating that suppression of NPY reduced eating.
Then, researchers split each of the groups into two, creating four sets of rats. One of the treated groups of rats and one of the control groups were fed a regular diet while the other treated and control groups got a high-fat diet. Of the rats on the regular diet, the control group weighed more at the end of 11 weeks than those rats in which hypothalamic NPY expression was knocked down. In the high-fat group, the control group rats became obese; those rats in which NPY expression was silenced gained less weight.
Bi says he believes that the transformation from white to brown fat resulting from NPY suppression may be due to activation of brown fat stem cells contained in white fat tissue. While brown fat seems to vanish in humans as they emerge from infancy, the brown fat stem cells may never disappear and may just become inactive as people age.
Bi says it may be possible to transplant or inject brown fat stem cells under the skin to burn white fat and stimulate weight loss. "Only future research will tell us if that is possible," he says. This study also shows that low levels of hypothalamic NPY increase spontaneous physical activity, improve blood sugar levels and enhance insulin sensitivity in rats, but it remains undetermined whether this brown fat transformation also contributes to these effects.
I found this article to extremely interesting. You cannot go a day without hearing about obesity on the news. I feel that this research can lead to a better, more natural way to help those who are obese lose weight.
Have you ever peered through a window at a sight that, from your experiences, holds the expectations of making a certain sound, and causing, within you, a certain reaction for that matter. Kaspar Meyer, of the University of Southern California, and colleagues used a serious of tests to show that the human brain will react in the same way to a sight whether or not the expected sounds accompany it. After observing the brain activity of a few volunteers who looked at a series of video clips, including people playing violins, a dog howling and chainsaws cutting into trees, Meyers and his colleagues were then able to determine which of this clips other volunteers were watching based solely on their brain activity responses. This was possible because the tests showed patterns in brain activity among the test subjects based upon the particular clip in which they were watching.