neurosciencestuff:

Researchers obtain key insights into how the internal body clock is tuned

Researchers at UT Southwestern Medical Center have found a new way that internal body clocks are regulated by a type of molecule known as long non-coding RNA.

The internal body clocks, called circadian clocks, regulate the daily “rhythms” of many bodily functions, from waking and sleeping to body temperature and hunger. They are largely “tuned” to a 24-hour cycle that is influenced by external cues such as light and temperature.

“Although we know that long non-coding RNAs are abundant in many organisms, what they do in the body, and how they do it, has not been clear so far,” said Dr. Yi Liu, Professor of Physiology. “Our work establishes a role for long non-coding RNAs in ‘tuning’ the circadian clock, but also shows how they control gene expression.”

Determining how circadian clocks work is crucial to understanding several human diseases, including sleep disorders and depression in which the clock malfunctions. The influence of a functional clock is evident in the reduced performance of shift workers and the jet lag felt by long-distance travellers.

Dr. Liu and his team were able to learn more about the circadian rhythms by studying model systems involving the bread mold, Neurospora crassa. The researchers found that the expression of a clock gene named frequency (frq) is controlled by a long non-coding RNA named qrf (frq backwards) − an RNA molecule that is complementary, or antisense, to frq. Unlike normal RNA molecules, qrf does not encode a protein, but it can control whether and how much frq protein is produced.

Specifically, qrf RNA is produced in response to light, and can then interfere with the production of the frq protein. In this way, qrf can “re-set” the circadian clock in a light-dependent way. This regulation works both ways: frq can also block the production of qrf. This mutual inhibition ensures that the frq and qrf RNA molecules are present in opposite “phases” of the clock and allows each RNA to oscillate robustly. Without qrf, normal circadian rhythms are not sustained, indicating that the long non-coding RNA is required for clock functions.

The findings are published online in the journal Nature.

“We anticipate a similar mode of action may operate in other organisms because similar RNAs have been found for clock genes in mice. In addition, such RNAs may also function in other biological processes because of their wide presence in genomes,” said Dr. Liu, who is the Louise W. Kahn Scholar in Biomedical Research.

UT Southwestern investigators are leaders in unraveling the gene networks underlying circadian clocks and have shown that most body organs, such as the pancreas and liver, have their own internal clocks, and that virtually every cell in the human body contains a clock. It now appears that the clocks and clock-related genes – some 20 such genes have been identified – affect virtually all of the cells’ metabolic pathways, from blood sugar regulation to cholesterol production.

Other UT Southwestern researchers involved in the latest findings include Dr. Zhihong Xue, Qiaohong Ye, Dr. Juchen Yang and Dr. Guanghua Xiao. Support for this research included grants from the National Institutes of Health, the Welch Foundation, the Cancer Prevention Research Institute of Texas, and the Biotechnology and Biological Sciences Research Council.

“This study adds to an important body of work that has shown the ubiquity of a circadian clock across species, including humans, and its role in metabolic regulation in cells, organs, and organisms,” said Dr. Michael Sesma, Program Director in the Division of Genetics and Developmental Biology at the of the National Institutes of Health’s National Institute of General Medical Sciences, which partially funded the research. “These new results from Dr. Liu and his colleagues also extend beyond understanding the function of an anti-sense RNA in the fine tuning of a cell’s daily rhythm; they provide an example of the means by which anti-sense transcription likely regulates other key molecular and physiological processes in cells and organisms.”

(Image: Fotolia)


 

 
  • Both he and Zimbardo (prison stimulation study) were classmates.
  • The man who played the learner in Milgram’s original study suffered a heart attack 3 years later and was resucitated by someone who had been a teacher in the study.
  • Milgram found an identical obedience rate of 65% between both men and women.
  • Milgram originally studied Political Science, and later changed so Social Psychology, which he was originally rejected for as he had no psychological background.
  • His study was originally put on hold by the APA (American Psychological Association) due to raised ethical issues, but was later passed.

 

 

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Crash Course Psychology #11: How To Train Your Brain. http://youtu.be/qG2SwE_6uVM


 

neurosciencestuff:

Training brain patterns of empathy using functional brain imaging

An unprecedented research conducted by a group of neuroscientists has demonstrated for the first time that it is possible to train brain patterns associated with empathic feelings – more specifically, tenderness. The research showed that volunteers who received neurofeedback about their own brain activity patterns whilst being scanned inside a functional magnetic resonance (fMRI) machine were able to change brain network function of areas related to tenderness and affection felt toward loved ones. These significant findings could open new possibilities for treatment of clinical situations, such as antisocial personality disorder and postpartum depression.

In Ridley Scott’s film “Blade Runner”, based on the science fiction book ‘Do androids dream of electric sheep?’ by Philip K. Dick, empathy-detection devices are employed to measure tenderness or affection emotions felt toward others (called “affiliative” emotions). Despite recent advances in neurobiology and neurotechnology, it is unknown whether brain signatures of affiliative emotions can be decoded and voluntarily modulated.

The article entitled “Voluntary enhancement of neural signatures of affiliative emotion using fMRI neurofeedback” published in PLOS ONE is the first study to demonstrate through a neurotechnology tool, real-time neurofeedback using functional Magnetic Resonance Imaging (fMRI), the possibility to help the induction of empathic brain states.

The authors conducted this research at the D’Or Institute for Research and Education where a sophisticated computational tool was designed and used to allow the participants to modulate their own brain activity related to affiliative emotions and enhance this activity. This method employed pattern-detection algorithms, called “support vector machines” to classify complex activity patterns arising simultaneously from tenths of thousands of voxels (the 3-D equivalent of pixels) inside the participants’ brains.

Volunteers who received real time information of their ongoing neural activity could change brain network function among connected areas related to tenderness and affection felt toward loved ones, while the control group who performed the same fMRI task without neurofeedback did not show such improvement.

Thus, it was demonstrated that those who received a “real” feedback were able to “train” specific brain areas related to the experience of affiliative emotions that are key for empathy. These findings can lead the way to new opportunities to investigate the use of neurofeedback in conditions associated with reduced empathy and affiliative feelings, such as antisocial personality disorders and post-partum depression.

The authors point out that this study may represent a step towards the construction of the ‘empathy box’, an empathy-enhancing machine described by Philip K. Dick’s novel.


 

 

neurosciencestuff:

Brain Scans Show We Take Risks Because We Can’t Stop Ourselves

A new study correlating brain activity with how people make decisions suggests that when individuals engage in risky behavior, such as drunk driving or unsafe sex, it’s probably not because their brains’ desire systems are too active, but because their self-control systems are not active enough.

This might have implications for how health experts treat mental illness and addiction or how the legal system assesses a criminal’s likelihood of committing another crime.

Researchers from The University of Texas at Austin, UCLA and elsewhere analyzed data from 108 subjects who sat in a magnetic resonance imaging (MRI) scanner — a machine that allows researchers to pinpoint brain activity in vivid, three-dimensional images — while playing a video game that simulates risk-taking.

The researchers used specialized software to look for patterns of activity across the whole brain that preceded a person’s making a risky choice or a safe choice in one set of subjects. Then they asked the software to predict what other subjects would choose during the game based solely on their brain activity. The software accurately predicted people’s choices 71 percent of the time.

“These patterns are reliable enough that not only can we predict what will happen in an additional test on the same person, but on people we haven’t seen before,” said Russell Poldrack, director of UT Austin’s Imaging Research Center and professor of psychology and neuroscience.

When the researchers trained their software on much smaller regions of the brain, they found that just analyzing the regions typically involved in executive functions such as control, working memory and attention was enough to predict a person’s future choices. Therefore, the researchers concluded, when we make risky choices, it is primarily because of the failure of our control systems to stop us.

“We all have these desires, but whether we act on them is a function of control,” said Sarah Helfinstein, a postdoctoral researcher at UT Austin and lead author of the study that appears online this week in the journal Proceedings of the National Academy of Sciences.

Helfinstein said that additional research could focus on how external factors, such as peer pressure, lack of sleep or hunger, weaken the activity of our brains’ control systems when we contemplate risky decisions.

“If we can figure out the factors in the world that influence the brain, we can draw conclusions about what actions are best at helping people resist risks,” said Helfinstein.

To simulate features of real-world risk-taking, the researchers used a video game called the Balloon Analogue Risk Task (BART) that past research has shown correlates well with self-reported risk-taking such as drug and alcohol use, smoking, gambling, driving without a seatbelt, stealing and engaging in unprotected sex.

While playing the BART, the subject sees a balloon on the screen and is asked to make either a risky choice (inflate the balloon a little and earn a few cents) or a safe choice (stop the round and “cash out,” keeping whatever money was earned up to that point). Sometimes inflating the balloon causes it to burst and the player loses all the cash earned from that round. After each successful balloon inflation, the game continues with the chance of earning another standard-sized reward or losing an increasingly large amount. Many health-relevant risky decisions share this same structure, such as when deciding how many alcoholic beverages to drink before driving home or how much one can experiment with drugs or cigarettes before developing an addiction.

The data for this study came from the Consortium for Neuropsychiatric Phenomics at UCLA, which recruited adults from the Los Angeles area for researchers to examine differences in response inhibition and working memory between healthy adults and patients diagnosed with bipolar disorder, schizophrenia, or adult attention deficit hyperactivity disorder (ADHD). Only data collected from healthy participants were included in the present analyses.


 

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