ucsdhealthsciences:

Scientists Discover “Dimmer Switch” For Mood Disorders
Researchers at University of California, San Diego School of Medicine have identified a control mechanism for an area of the brain that processes sensory and emotive information that humans experience as “disappointment.”
The discovery of what may effectively be a neurochemical antidote for feeling let-down is reported Sept. 18 in the online edition of Science.
“The idea that some people see the world as a glass half empty has a chemical basis in the brain,” said senior author Roberto Malinow, MD, PhD, professor in the Department of Neurosciences and neurobiology section of the Division of Biological Sciences. “What we have found is a process that may dampen the brain’s sensitivity to negative life events.”
Because people struggling with depression are believed to register negative experiences more strongly than others, the study’s findings have implications for understanding not just why some people have a brain chemistry that predisposes them to depression but also how to treat it.
Specifically, in experiments with rodents, UC San Diego researchers discovered that neurons feeding into a small region above the thalamus known as the lateral habenula (LHb) secrete both a common excitatory neurotransmitter, glutamate, and its opposite, the inhibitory neurotransmitter GABA.
Excitatory neurotransmitters promote neuronal firing while inhibitory ones suppress it, and although glutamate and GABA are among two of the most common neurotransmitters in the mammalian brain, neurons are usually specialists, producing one but not both kinds of chemical messengers.
Indeed, prior to the study, there were only two other systems in the brain where neurons had been observed to co-release excitatory and inhibitory neurotransmitters – in a particular connection in the hippocampus and in the brainstem during development of the brain’s auditory map.
“Our study is one of the first to rigorously document that inhibition can co-exist with excitation in a brain pathway,” said lead author Steven Shabel, a postdoctoral researcher with Department of Neurosciences and neurobiology section of the Division of Biological Sciences. “In our case, that pathway is believed to signal disappointment.”
The LHb is a small node-like structure in the epithalamus region of the brain that is critical for processing a variety of inputs from the basal ganglia, hypothalamus and cerebral cortex and transmitting encoded responses (output) to the brainstem, an ancient part of the brain that mammals share with reptiles.
Experiments with primates have shown that activity in the LHb increases markedly when monkeys are expecting but don’t get a sip of fruit juice or other reward, hence the idea that this region is part of a so-called disappointment pathway.
Proper functioning of the LHb, however, is believed to be important in much more than just disappointment and has been implicated in regulating pain responses and a variety of motivational behaviors. It has also been linked to psychosis.
Depression, in particular, has been linked to hyperactivity of the LHb, but until this study, researchers had little empirical evidence as to how this overstimulation is prevented in healthy individuals given the apparent lack of inhibitory neurons in this region of the brain.
"The take-home of this study is that inhibition in this pathway is coming from an unusual co-release of neurotransmitters into the habenula," Shabel said. Researchers do not know why this region of the brain is controlled in this manner, but one hypothesis is that it allows for a more subtle control of signaling than having two neurons directly counter-acting each other.
Researchers were also able to show that neurons of rodents with aspects of human depression produced less GABA, relative to glutamate. When these animals were given an antidepressant to raise their brain’s serotonin levels, their relative GABA levels increased.
"Our study suggests that one of the ways in which serotonin alleviates depression is by rebalancing the brain’s processing of negative life events vis-à-vis the balance of glutamate and GABA in the habenula," Shabel said. "We may now have a precise neurochemical explanation for why antidepressants make some people more resilient to negative experiences."
Pictured: Basal ganglia neurons (green) feed into the brain and release glutamate (red) and GABA (blue) and sometimes a mix of both neurotransmitters (white).

ucsdhealthsciences:

Scientists Discover “Dimmer Switch” For Mood Disorders

Researchers at University of California, San Diego School of Medicine have identified a control mechanism for an area of the brain that processes sensory and emotive information that humans experience as “disappointment.”

The discovery of what may effectively be a neurochemical antidote for feeling let-down is reported Sept. 18 in the online edition of Science.

“The idea that some people see the world as a glass half empty has a chemical basis in the brain,” said senior author Roberto Malinow, MD, PhD, professor in the Department of Neurosciences and neurobiology section of the Division of Biological Sciences. “What we have found is a process that may dampen the brain’s sensitivity to negative life events.”

Because people struggling with depression are believed to register negative experiences more strongly than others, the study’s findings have implications for understanding not just why some people have a brain chemistry that predisposes them to depression but also how to treat it.

Specifically, in experiments with rodents, UC San Diego researchers discovered that neurons feeding into a small region above the thalamus known as the lateral habenula (LHb) secrete both a common excitatory neurotransmitter, glutamate, and its opposite, the inhibitory neurotransmitter GABA.

Excitatory neurotransmitters promote neuronal firing while inhibitory ones suppress it, and although glutamate and GABA are among two of the most common neurotransmitters in the mammalian brain, neurons are usually specialists, producing one but not both kinds of chemical messengers.

Indeed, prior to the study, there were only two other systems in the brain where neurons had been observed to co-release excitatory and inhibitory neurotransmitters – in a particular connection in the hippocampus and in the brainstem during development of the brain’s auditory map.

“Our study is one of the first to rigorously document that inhibition can co-exist with excitation in a brain pathway,” said lead author Steven Shabel, a postdoctoral researcher with Department of Neurosciences and neurobiology section of the Division of Biological Sciences. “In our case, that pathway is believed to signal disappointment.”

The LHb is a small node-like structure in the epithalamus region of the brain that is critical for processing a variety of inputs from the basal ganglia, hypothalamus and cerebral cortex and transmitting encoded responses (output) to the brainstem, an ancient part of the brain that mammals share with reptiles.

Experiments with primates have shown that activity in the LHb increases markedly when monkeys are expecting but don’t get a sip of fruit juice or other reward, hence the idea that this region is part of a so-called disappointment pathway.

Proper functioning of the LHb, however, is believed to be important in much more than just disappointment and has been implicated in regulating pain responses and a variety of motivational behaviors. It has also been linked to psychosis.

Depression, in particular, has been linked to hyperactivity of the LHb, but until this study, researchers had little empirical evidence as to how this overstimulation is prevented in healthy individuals given the apparent lack of inhibitory neurons in this region of the brain.

"The take-home of this study is that inhibition in this pathway is coming from an unusual co-release of neurotransmitters into the habenula," Shabel said. Researchers do not know why this region of the brain is controlled in this manner, but one hypothesis is that it allows for a more subtle control of signaling than having two neurons directly counter-acting each other.

Researchers were also able to show that neurons of rodents with aspects of human depression produced less GABA, relative to glutamate. When these animals were given an antidepressant to raise their brain’s serotonin levels, their relative GABA levels increased.

"Our study suggests that one of the ways in which serotonin alleviates depression is by rebalancing the brain’s processing of negative life events vis-à-vis the balance of glutamate and GABA in the habenula," Shabel said. "We may now have a precise neurochemical explanation for why antidepressants make some people more resilient to negative experiences."

Pictured: Basal ganglia neurons (green) feed into the brain and release glutamate (red) and GABA (blue) and sometimes a mix of both neurotransmitters (white).

19

September

380 notes

This photo was reblogged from neurosciencestuff and originally by ucsdhealthsciences.

lindahall:

Ole Rømer - Scientist of the Day

Ole Rømer, a Danish astronomer, died on Sep. 19, 1710, at age 65. Rømer is best known for the 8 years he spent at the Paris Observatory, where he was the first to determine, from a study of the moons of Jupiter, that light has a finite speed. But in 1680, Rømer returned to Copenhagen, was appointed professor of astronomy at the University, and spent the remainder of his career using specially constructed instruments, such as his transit instrument (see first image above), to make detailed observations of the planets and stars. The instruments, property of the University, were installed on the top of the famous Rundetårn or Round Tower in Copenhagen (see second image above), but because Rømer was not happy with the observing conditions (it was often windy), he built his own small observatory outside the city. Unfortunately, in 1728, after his death, a terrible fire raced through downtown Copenhagen, and although the stone tower survived, all of Rømer’s instruments and observations perished in the conflagration. Fortunately, his pupil and colleague Peder Horrobow published in 1735 a description of Rømer’s life and work, from which all the engravings above were taken.

The portrait of Rømer was made about 1700 and hangs in the Fredericksborg Palace in Hillerød, Denmark.

Dr. William B. Ashworth, Jr., Consultant for the History of Science, Linda Hall Library and Associate Professor, Department of History, University of Missouri-Kansas City

19

September

15 notes

This photo was reblogged from lindahall and originally by lindahall.

(Source: facebook.com)

19

September

179 notes

This photo was reblogged from somuchscience and originally by dimensao7.

emilyhromi:

Some occipital bone sketches for Forensic Imaging & Modeling, Fall 2013.

19

September

171 notes

This photo was reblogged from brains-and-bodies and originally by emilyhromi.

nubbsgalore:

astrophotography by matt payne in coloardo and oregon. the panoramas seen here are created by stitching up to twenty photos together. (see also: previous astrophotography)  

19

September

15,837 notes

This photo was reblogged from shinyshiney and originally by nubbsgalore.

tulipnight:

Kamchatka by Eugene Kaspersky on Flickr.

tulipnight:

Kamchatka by Eugene Kaspersky on Flickr.

17

September

278 notes

This photo was reblogged from astrogasmic and originally by tulipnight.

vainajala:

 we have forests like this here in finland

vainajala:

 we have forests like this here in finland

(Source: vainaja)

17

September

14,051 notes

This photo was reblogged from chloroformfuck and originally by vainaja.

ggeology:

Australian Opal

ggeology:

Australian Opal

(Source: ggeology)

17

September

406 notes

This photo was reblogged from chloroformfuck and originally by ggeology.

curiosamathematica:

A hyperbola of one sheet can be traced by a straight line, making it a ruled surface. You can make a beautiful real-life model by connecting two circles with some elastic strings, and rotating one of the circles; here’s a virtual Wolfram Demonstration.

curiosamathematica:

A hyperbola of one sheet can be traced by a straight line, making it a ruled surface. You can make a beautiful real-life model by connecting two circles with some elastic strings, and rotating one of the circles; here’s a virtual Wolfram Demonstration.

17

September

79 notes

This photo was reblogged from the-science-of-time and originally by curiosamathematica.

unacted:

girls who pretend to act stupid because they think it’s cute need to be slapped in the face with a brick

(Source: isilence)

17

September

382,736 notes

This text was reblogged from curingcoldswithantibiotics and originally by isilence.

cyclopentadiene:

"No homo," I whisper as I add sodium hydride to my reaction. The strong base pulls protons off of my amine, heterolytically cleaving the N-H bond. I am a chemist.

14

September

204 notes

This text was reblogged from cyclopentadiene and originally by cyclopentadiene.

labphoto:

Doing experiments with an aerobic oxidation using a copper-amine complex as a catalyst. 
The 7 colorful solution in the vials are reaction mixtures with the same reactants in different solvents (methanol, ethanol, propanol, acetonitrile, ethyl-acetate, diemthylformamide, dimethylsulfoxide, ect.). Here I would like to know that which solvents could be used for this oxidation. 
Luckily in 40% of the solvents, something happened.

labphoto:

Doing experiments with an aerobic oxidation using a copper-amine complex as a catalyst. 

The 7 colorful solution in the vials are reaction mixtures with the same reactants in different solvents (methanol, ethanol, propanol, acetonitrile, ethyl-acetate, diemthylformamide, dimethylsulfoxide, ect.). Here I would like to know that which solvents could be used for this oxidation. 

Luckily in 40% of the solvents, something happened.

14

September

61 notes

This photo was reblogged from labphoto and originally by labphoto.

coeurensabot:

the thing about chemical weapons and war contaminants—including tear gas—is that their use is always deliberate. they have their immediate effects—killing and injuring people—but the long term effects are even more insidious. chemical weapons (and I use this term deliberately) can cause long term disability and illness in people immediately exposed to them—think cancer, chemical injury, nerve damage, pulmonary and respiratory illnesses, etc.

but even more distressing than that, is research that demonstrates the long term impact of these chemical agents on environments and communities. this shit stays in the air, the soil, the water. exposure causes not only injury and illness to people immediately in the line of fire, it can cause birth anomalies long after the conflict has ceased. add in the fact that these kinds of weapons are deployed against marginalized populations whose access to healthcare is restricted, and you have effectively suppressed and marginalized not only the current generation, but future ones as well.

There is not a lot of research on this, because these weapons are deployed against people the state wants dead anyway— in our current context, Black people in the US and Palestinians in Gaza. let me be real clear about this: chemical weapons are being deployed against Black people by police; this is directed chemical warfare motivated by racism. 

So with tear gas, you get this funny thing where police are praised for using “less lethal” measures, when in fact the long term consequences are pretty damn lethal, but all of that gets covered up by time and distance and “lack of research”. 

There is a pattern here of dumping toxic shit on people, either through outright violence or through industrial environmental degradation (or both!), and then shrugging when a host of ongoing health problems emerge. In particular, use of chemical weapons constitutes an ongoing act of violence designed to disable and surpress populations. Tear gas is different in degree, not in kind.

Some links on this below the cut:

Read More

14

September

203 notes

This text was reblogged from coeurensabot and originally by coeurensabot.

cybermax:

future-punk:

Eruption of Mount Tavurvur

I like the fact that you can see the shockwave go through the clouds.

cybermax:

future-punk:

Eruption of Mount Tavurvur

I like the fact that you can see the shockwave go through the clouds.

14

September

5,095 notes

This photo was reblogged from ptolemy2 and originally by future-punk.

"We could write a proof for this, but let’s just understand it instead."

- Analysis professor (via mathprofessorquotes)

14

September

323 notes

This quote was reblogged from enjoy-science and originally by mathprofessorquotes.

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