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a pair of researchers

has discovered how fear can actually increase or decrease the ability to discriminate among sounds depending on context

study

emotional conditioning in mice to investigate how hearing acuity (the ability to distinguish between tones of different frequencies) can change following a traumatic event, known as emotional learning

In these experiments

animals learn to distinguish between potentially dangerous and safe sounds—called "emotional discrimination learning."

This type of conditioning tends to result in relatively poor learning, but

designed a series of learning tasks intended to create progressively greater emotional discrimination in the mice, varying the difficulty of the

The researchers found that, as expected, fine emotional learning tasks produced greater learning specificity than tests in which the tones were farther apart in frequency

animals presented with sounds that were very far apart generalize the fear that they developed to the danger tone over a whole range of frequencies

animals presented with the two sounds that were very similar exhibited specialization of their emotional response

pitch discrimination abilities were measured in the animals, the mice with more specific responses displayed much finer auditory acuity than the mice who were frightened by a broader range of frequencies

Another interesting finding of this study is that the effects of emotional learning on hearing perception were mediated by a specific brain region, the auditory cortex

The auditory cortex has been known as an important area responsible for auditory plasticity

Surprisingly

found that the auditory cortex did not play a role in emotional learning

the specificity of emotional learning is controlled by the amygdala and sub-cortical auditory areas

hypothesis is that the amygdala and cortex are modifying subcortical auditory processing areas. The sensory cortex is responsible for the changes in frequency discrimination, but it's not necessary for developing specialized or generalized emotional responses

These fibers, or axons, are the long extensions that convey signals from one end of a neuron to another, and unfortunately, they don't regrow in adults

Restoring axons' ability to regrow using growth factors, stem cells, or other therapies has been a longstanding—but frustratingly elusive—goal for researchers.

Most spinal injuries in people do not sever the spinal cord completely

To approximate this situation in rats, his team made two surgical cuts in the spinal cord, severing all of the direct connections from the brain, but leaving some tissue intact in between the cuts

had the rodents begin a rehab regime intended to bypass the fractured freeway, as it were, by pushing more traffic onto neural back roads and building more of them

This regime, which began about a week after the rats were injured, lasted about 30 minutes a day

During each session, the researchers injected the animals with a cocktail of drugs to improve the function of rats' neural circuits in the part of the spinal cord involved in leg movements

stimulated this area with electrodes

With its spinal cord thus primed for action, a rat was fitted into a harness attached to a robotic device that supported its weight and allowed it to walk forward on its hind legs to the extent that it was able

At first, the rats could not move their legs at all, let alone walk.

after 2 or 3 weeks, the rodents began taking steps toward a piece of food after a gentle nudge from the robo

By 5 or 6 weeks, they were able to initiate movement on their own and walk to get the food

after a few additional weeks of intensified rehab, they were able to walk up rat-sized stairs and climb over a small barrier placed in their path

did not undergo rehab, in contrast, showed no improvement at all

Rats suspended over a moving treadmill that elicited reflex-like stepping movement

full recovery depends on making intentional movements, not just any movement

Additional experiments in the paper make a compelling case that the rats' recovery is due to new neural connections forming to create a detour around the injury

s work suggests that all three components of the rehab strategy—the drugs, the electrical stimulation, and the robot-assisted physical therapy

case study published last year reported some recovery of voluntary movements in a man paralyzed in a vehicle accident, after he underwent a combination of electrical stimulation and physical therap

two more patients are undergoing similar rehab now, and his group hopes to add drug therapy to enhance nerve repair in the future

the strategy's limitations. For one thing, it wouldn't work if the spinal cord were completely severed

treated rats could only make voluntary movements while the electrical stimulation was turned on, and the same was mostly true of the patient Edgerton and colleagues worked with. "This is not a cure for spinal cord injury," Courtine says. "It's a promising proof of principle."

neuroscientists

found that the neurotransmitters gamma-aminobutyric acid (GABA) and glycine caused REM sleep paralysis in rats by "switching off" the specialized cells in the brain that allow muscles to be active

reversed earlier beliefs that glycine was a lone inhibitor of these motor neurons.

By identifying the neurotransmitters and receptors involved in sleep-related paralysis, this study points us to possible molecular targets for developing treatments for sleep-related motor disorders

Previous research suggested neurotransmitter receptors called ionotropic GABAA/glycine receptors in the motor neurons caused REM sleep paralysis

when the researchers blocked these receptors, REM sleep paralysis still occurred.

to prevent REM sleep paralysis, they had to block both the ionotropic receptors and metabotropic GABAB receptors, a different receptor system

when the motor cells were cut off from all sources of GABA and glycine, the paralysis did not occur

suggest the two neurotransmitters must both be present together to maintain motor control during sleep

finding could be especially helpful for those with REM sleep disorder, a disease that causes people to act out their dreams

levels of the enzyme, salivary alpha-amylase (sAA), were lower than those of typically developing children in samples taken in the afternoon in

samples taken at home throughout the day showed that sAA levels were higher in general across the day and much less variable for children with ASD

sAA levels of typically developing children gradually rise and fall over the day

Norepinephrine (NE) has been found in the blood plasma levels of individuals with ASD, but some researchers have questioned whether these levels were just related to the stress from blood draws

collecting salivary measures by simply placing a highly absorbent sponge swab under the child’s tongue and confirmed that this method of collection did not stress the children by assessing their stress levels through cortisol, another hormone

potential for physicians to screen children for ASD much earlier, noninvasively and relatively inexpensively

also see pupil size and sAA levels as biomarkers

Many theories of autism propose that the disorder is due to deficits in higher-order brain areas

Our findings, however, suggest that the core deficits may lie in areas of the brain typically associated with more fundamental, vital functions

study, published online in the May 29, 2012

compared children between the ages of 20 and 72 months of age diagnosed with ASD to a group of typically developing children and a third group of children with Down syndrome

a neurobiologist at University of California–Irvine

Huntington’s disease occurs when the C-A-G sequence of DNA base pairs repeat too often on the HTT gene, resulting in an abnormally long version of the huntingtin protein, that therefore folds incorrectly and forms clumps in the brain

usually begins to affect people in their 30s and 40s, causing movement problems and early death

No drug is currently available to stop the disease from progressing

For their experiment, researchers fed methylene blue mixed with food for a week to Drosophila flies

brains showed that protein clumps had been reduced by 87 percent compared with a control group

given methylene blue

underwent several tests to assess mobility

At two months of age, the treated mice showed abnormal clasping of their hind claws only 20 percent of the time

untreated counterparts clasped at a 60 percent rate

the number of mice used was not sufficient to provide statistically significant results and the difference in the test quickly dropped off at nine weeks of age

the data as hopeful, because even a delay in Huntington’s symptoms would be very helpful

more research is needed

Methylene blue would absolutely require further testing in mouse models and would need safety and efficacy trial before it could be used for humans."

This study shows promise pre-clinically and follow-up studies are needed in a more representative mouse model that expresses the full-length Huntingtin protein

Let's ignore, for example, the homeopathic notion that illness is caused by a disturbance in an individual's "vital force" rather than something external, like a bacterium or virus

Another thing homeopathy has in common with Western medicine is its strict attention to how treatments are dosed

All homeopathic remedies are available in a huge range of concentrations

those concentrations are really small

homeopaths think of a large dose as a high dilution, instead of a high concentration.

idea that a lower dose of a drug has a bigger effect than a high dose runs contrary to what western medicine has found

that revealed that musicians with at least 10 years of instrumental musical training remained cognitively sharp in advanced age

range of cognitive benefits, including memory, was sustained for musicians between the ages of 60-80 if they played for at least 10 years throughout their life

While years of playing music were the best indication of enhanced cognition in advanced age, the results revealed different sensitive periods for cognitive development across the lifespan

before age nine, predicted verbal working memory functions

Sustained musical activity in advanced age predicted other non-verbal abilities involving visuospatial judgment, suggesting it is never too late to be musically active

Continued musical activity in advanced age also appeared to buffer lower educational levels

to obtain optimal results, individuals should start musical training before age nine, play at least 10 years or more and if possible, keep playing for as long as possible over the age of 60.

hibernation simply refers to the seasonal bodily changes that occur in some animals—slower heart rates, decreased oxygen intake, and a reduced ability to regulate body temperature

during hibernation, a lemur’s breathing can slow to one inhalation every 20 minutes, and its heart rate drops from a normal 200 beats per minute to just 4 beats per minute

lemurs can hibernate, surviving three-quarters of a year without deep sleep,

The longest a human has ever been recorded going without sleep is allegedly 18 days, 21 hours, and 40 minutes

severely sleep-deprived humans have a tendency to fall asleep for seconds at a time, it’s hard to prove such claims without brain monitoring

rapid eye movement (REM) sleep—which is when we dream

non-REM sleep. Non-REM sleep is vital. When you fall into bed after pulling an all-nighter

deep, non-REM sleep that you want

when lemurs hibernate, scientists speculate that they experience only REM sleep. Though no one can prove whether lemurs actually dream

primates exhibit all the telltale signs of a full night’s REM sleep such as increased brain activity, rapid eye movements, and muscle paralysis

A 1989 study by sleep scientist

demonstrated the lethal consequences of sleep deprivation

When the researcher kept ten rats awake, depriving them of non-REM sleep, they developed skin lesions, lost weight, and experienced an erosion of their gastrointestinal tracts.

After 32 days, all of the rats were dead

If you completely deprive animals of [non-REM] sleep, then they die

yet the lemurs that hibernate appear to be able to go for months without sleep…and they’re not dying

Lemurs in captivity often don’t hibernate

Some of [the lemurs hibernated] 40 feet off the ground in the middle of the forest in coastal Madagascar

team visited the primates in their natural habitat—Madagascar

By placing the lemurs in special nesting boxes and attaching EEGs to their tiny foreheads while they hibernated, Krystal was able to record their vital signs

found that when it was warm outside, close to 72 degrees Fahrenheit (22 degrees Celsius), the primates would only hibernate in REM sleep.

As temperatures inside the body fall, several failsafe systems spring into action

Blood vessels near the skin squeeze tight to hold warmth in, the body starts to shiver and brown fat, a tissue that’s especially plentiful in newborns, starts to produce heat

colleagues bypassed the rats’ defenses against the cold with a compound that’s similar to adenosine, a molecule in the body that signals sleepiness

After about an hour in a room chilled to 15° Celsius, the rats grew lethargic

brain waves slowed, their blood pressure dropped and their heart grew sluggish, occasionally skipping beats

The rats’ core temperature dropped from about 38°  to about 30° C, or 80° Fahrenheit

measured even lower temperatures in further experiments — rats’ core body temperature reached 15° C or about 57° F.

The rats weren’t in a coma, nor were they asleep or truly hibernating

Hibernating animals’ metabolisms plummet and their temperatures sink much lower

an Arctic ground squirrel, for instance, cools to about —3° C when it hibernates

It’s a new state

don’t really know what it is

In the experiment, loud noises and tail pinches failed to arouse the rats.

They didn’t eat or drink. Occasionally, one would slither into a corner, but for the most part, the animals stayed still for up to 6 hours

In unpublished experiments, Tupone has kept the animals in the unresponsive state for 24 hours, he says.

Warming the room coaxed the rats out of their torpor

The recovery process takes about 12 hours, during which the animals ate and drank voraciously

After recovering, the animals were alert, moved around their cages normally and slept when tired

When people have heart attacks or strokes, clinicians can use ice packs or frigid water to chill people and prevent further tissue damage

those methods of cooling take time and can have dangerous side effects

"These findings demonstrate that prolonged blue light exposure during the day has an an alerting effect."

researchers measured wavelengths of light that were most effective in warding off fatigue via the development of specialized light equipment

compared the effects of blue light exposure to an equal amount of green light on alertness and performance in 16 study participants for 6.5 hours over a day.

participants were rated based on how they felt through reaction times that measured electrodes to assess changes going on in the brain due to light exposure.

Results showed that participants exposed to blue light consistently rated themselves as less sleepy with quicker reaction times and fewer attention relapses.

They also showed changes in brain activity patterns that indicated a more alert state.

open up a new range of possibilities for using light to improve human alertness, productivity and safety

helping to improve alertness in night workers has obvious safety benefits, day shift workers may also benefit

better quality lighting that would not only help them see better but also make them more alert

next big challenge is to determine how to deliver better lighting in many places

such as schools, homes and work places that could

provide a more productive and alert atmosphere.

17 January – NASA announces that the Kepler space observatory has developed a reaction wheel issue

2 January A study by Caltech astronomers reports that the Milky Way Galaxy contains at least one planet per sta

3 January

8 January

20 January – Scientists prove that quadruple-helix DNA is present in human cells

25 January

An international team of scientists develops a functional light-based "tractor beam", which allows individual cells to be selected and moved at will. The invention could have broad applications in medicine and microbiology

30 January – South Korea conducts its first successful orbital launch

6 February

Astronomers report that 6% of all dwarf stars – the most common stars in the known universe – may host Earthlike planets

Scientists discover live bacteria in the subglacial Antarctic Lake Whillans

American scientists finish drilling down to the subglacial Lake Whillans, which is buried around 1 kilometre (0.62 mi) under the Antarctic ice

10 February NASA's Curiosity Mars rover uses its onboard drill to obtain the first deep rock sample ever retrieved from the surface of another plane

15 February A 10-ton meteoroid impacts in Chelyabinsk, Russia, producing a powerful shockwave and injuring over 1,000 people

28 February

Astronomers make the first direct observation of a protoplanet forming in a disk of gas and dust around a distant sta

A third radiation belt is discovered around the Eart

1 March – Boston Dynamics demonstrates an updated version of its BigDog military robot

3 March – American scientists report that they have cured HIV in an infant by giving the child a course of antiretroviral drugs very early in its life. The previously HIV-positive child has reportedly exhibited no HIV symptoms since its treatment, despite having no further medication for a year

researchers replace 75 percent of an injured patient's skull with a precision 3D-printed polymer replacement implant. In future, damaged bones may routinely be replaced with custom-manufactured implants

7 March

A study concludes that heart disease was common among ancient mummies

11 March

12 March NASA's Curiosity rover finds evidence that conditions on Mars were once suitable for microbial life after analyzing the first drilled sample of Martian rock, "John Klein" rock at Yellowknife Bay in Gale Crater. The rover detected water, carbon dioxide, oxygen, sulfur dioxide, hydrogen sulfide, chloromethane and dichloromethane. Related tests found results consistent with the presence of smectite clay minerals

14 March CERN scientists confirm, with a very high degree of certainty, that a new particle identified by the Large Hadron Collider in July 2012 is the long-sought Higgs boson

18 March

NASA reports evidence from the Curiosity rover on Mars of mineral hydration, likely hydrated calcium sulfate, in several rock samples, including the broken fragments of "Tintina" rock and "Sutton Inlier" rock as well as in the veins and nodules in other rocks like "Knorr" rock and "Wernicke" rock.[177] Analysis using the rover's DAN instrument provided evidence of subsurface water, amounting to as much as 4% water content, down to a depth of 60 cm

27 March – A potential new weight loss method is discovered, after a 20% weight reduction was achieved in mice simply by having their gut microbes altered.

NASA scientists report that hints of dark matter may have been detected by the Alpha Magnetic Spectrometer on the International Space Station

3 April

15 April A functional lab-grown kidney is successfully transplanted into a live rat in Massachusetts General Hospital

18 April – NASA announces the discovery of three new Earthlike exoplanets – Kepler-62e, Kepler-62f, and Kepler-69c – in the habitable zones of their respective host stars, Kepler-62 and Kepler-69. The new exoplanets, which are considered prime candidates for possessing liquid water and thus potentially life, were identified using the Kepler spacecraft

21 April The Antares rocket, a commercial launch vehicle developed by Orbital Sciences Corporation, successfully conducts its maiden flight

After years of unpowered glide tests, Scaled Composites' SpaceShipTwo hybrid spaceplane successfully conducts its first rocket-powered fligh

29 April

1 May IBM scientists release A Boy and His Atom, the smallest stop-motion animation ever created, made by manipulating individual carbon monoxide molecules with a scanning tunnelling microscope

A new study finds that children whose parents suck on their pacifiers have fewer allergies later in life

NASA reports that a reaction wheel on the Kepler space observatory may be malfunctioning and may result in the premature termination of the observatory's search for Earth-like

15 May

16 May Water dating back 2.6 billion years, by far the oldest ever found, is discovered in a Canadian mine

27 May Four-hundred-year-old bryophyte specimens left behind by retreating glaciers in Canada are brought back to life in the laboratory

29 May

Russian scientists announce the discovery of mammoth blood and well-preserved muscle tissue from an adult female specimen in Siberia

A new treatment to "reset" the immune system of multiple sclerosis patients is reported to reduce their reactivity to myelin by 50 to 75 percent

4 June

During the Shenzhou 10 mission, Chinese astronauts deliver the country's first public video broadcast from the orbiting Tiangong-1 space laboratory

20 June

China's Shenzhou 10 manned spacecraft returns safely to Earth, having conducted China's longest manned space mission to date

26 June

20 June

20 June

6 July

Scientists report that a wide variety of microbial life exists in the subglacial Antarctic Lake Vostok, which has been buried in ice for around 15 million years. Samples of the lake's water obtained by drilling were found to contain traces of DNA from over 3,000 tiny organisms

15 July

ASA engineers successfully test a rocket engine with a fully 3D-printed injector

19 July

NASA scientists publish the results of a new analysis of the atmosphere of Mars, reporting a lack of methane around the landing site of the Curiosity rover

Earth is photographed from the outer solar system. NASA's Cassini spacecraft releases images of the Earth and Moon taken from the orbit of Saturn

29 July – Astronomers discover the first exoplanet orbiting a brown dwarf, 6,000 light years from Earth

exoplanet

7 January

Astronomers

report that "at least 17 billion" Earth-sized exoplanets are estimated to reside in the Milky Way Galaxy

20 February

NASA reports the discovery of Kepler-37b, the smallest exoplanet yet known, around the size of Earth's Moon

10 June

Scientists report that the earlier claims of an Earth-like exoplanet orbiting Alpha Centauri B, a star close to our Solar System, may not be supported by astronomical evidence

25 June – In an unprecedented discovery, astronomers detect three potentially Earthlike exoplanets orbiting a single star in the Gliese 667

11 July For the first time, astronomers determine the true colour of a distant exoplanet. HD 189733 b, a searing-hot gas giant, is said to be a vivid blue colour, most likely due to clouds of silica in its atmosphere

NASA announces that the failing Kepler space observatory may never fully recover. New missions are being considered

15 August

Phase I clinical trials of SAV001 – the first and only preventative HIV vaccine – have been successfully completed with no adverse effects in all patients. Antibody production was greatly boosted after vaccination

3 September

12 September NASA announces that Voyager I has officially left the Solar System, having travelled since 1977

NASA scientists report the Mars Curiosity rover detected "abundant, easily accessible" water (1.5 to 3 weight percent) in soil samples

26 September

In addition, the rover found two principal soil types: a fine-grained mafic type and a locally derived, coarse-grained felsic type

mafic

as associated with hydration of the amorphous phases of the soi

perchlorates, the presence of which may make detection of life-related organic molecules difficult, were found at the Curiosity rover landing site

earlier at the more polar site of the Phoenix lander) suggesting a "global distribution of these salts

Astronomers have created the first cloud map of an exoplanet, Kepler-7b

30 September

8 October The Nobel Prize in Physics has been awarded to François Englert and Peter Higgs "for the theoretical discovery of a mechanism that contributes to our understanding of the origin of mass of subatomic particles, and which recently was confirmed through the discovery of the predicted fundamental particle, by the ATLAS and CMS experiments at CERN's Large Hadron Collider"

16 October Russian authorities raise a large fragment, 654 kg (1,440 lb) total weight, of the Chelyabinsk meteor, a Near-Earth asteroid that entered Earth's atmosphere over Russia on 15 February 2013, from the bottom of Chebarkul lake.

Researchers have shown that a fundamental reason for sleep is to clean the brain of toxins. This is achieved by brain cells shrinking to create gaps between neurons, allowing fluid to wash through

17 October

22 October – Astronomers have discovered the 1,000th known exoplanet

4 November - Astronomers report, based on Kepler space mission data, that there could be as many as 40 billion Earth-sized planets orbiting in the habitable zones of sun-like stars and red dwarf stars within the Milky Way Galaxy

11 billion of these estimated planets may be orbiting sun-like stars

5 November – India launches its first Mars probe, Mangalyaan

The IceCube Neutrino Observatory has made the first discovery of very high energy neutrinos on Earth which had originated from beyond our Solar System

21 November

1 December – China launches the Chang'e 3 lunar rover mission, with a planned landing on December 16

3 December – The Hubble Space Telescope has found evidence of water in the atmospheres of five distant exoplanets: HD 209458b, XO-1b, WASP-12b, WASP-17b and WASP-19b

9 December NASA scientists report that the planet Mars had a large freshwater lake (which could have been a hospitable environment for microbial life) based on evidence from the Curiosity rover studying Aeolis Palus near Mount Sharp in Gale Crater

12 December NASA announces, based on studies with the Hubble Space Telescope, that water vapor plumes were detected on Europa, moon of Jupiter

14 December – The unmanned Chinese lunar rover Chang'e 3 lands on the Moon, making China the third country to achieve a soft landing there

18 December

nomers have spotted what appears to be the first known "exomoon", located 1,800 light years away

20 December – NASA reports that the Curiosity rover has successfully upgraded, for the third time since landing, its software programs and is now operating with version 11. The new software is expected to provide the rover with better robotic arm and autonomous driving abilities. Due to wheel wear, a need to drive more carefully, over the rough terrain the rover is currently traveling on its way to Mount Sharp, was also reported