[ik-splohr]

Other blogs: Skies Colors Fun.Loves Arashi DIY Me Creativity

[neurosciencestuff]

Is a Marker of Preclinical Alzheimer Disease Associated with Loneliness?

A new article published online by JAMA Psychiatry used data from a study of 79 cognitively normal adults to examine whether cortical amyloid levels in the brain, a marker of preclinical Alzheimer disease, was associated with self-reported loneliness.

Alzheimer disease (AD) is a process that moves through preclinical, mild cognitive impairment and dementia stages before it leads to progressive neuropsychiatric, cognitive and functional declines. Loneliness has been associated with cognitive and functional decline and an increased risk of AD dementia.

Nancy J. Donovan, M.D., of Brigham and Women’s Hospital and Harvard Medical School, Boston, and coauthors used imaging as a measure of cortical amyloid levels in the brain and a loneliness scale to indicate levels of loneliness. The study included 43 women and 36 men with an average age of about 76.

Of the participants, 22 (28 percent) were carriers of the genetic risk factor apolipoprotein E ɛ4 (APOEɛ4) and 25 (32 percent) were in the amyloid-positive group based on volume in imaging. The participants’ average loneliness score was 5.3 on a scale of 3 to 12.

The authors report higher cortical amyloid levels were associated with greater loneliness after controlling for age, sex, APOEɛ4, socioeconomic status, depression, anxiety and social network. Participants in the amyloid-positive group were 7.5 times more likely to be classified as lonely then nonlonely compared with individuals in the amyloid-negative group. The association between high amyloid levels and loneliness also was stronger in APOEɛ4 carriers than in noncarriers, according to the results.

Limitations of the study include the demographic profile of the participants who had high intelligence and educational attainment but limited racial and socioeconomic diversity. The participants also had better mental and physical health.

“We report a novel association of loneliness and cortical amyloid burden in cognitively normal adults and present evidence for loneliness as a neuropsychiatric symptom relevant to preclinical AD. This work will inform new research into the neurobiology of loneliness and other socioemotional changes in late life and may enhance early detection and intervention research in AD,” the study concludes.

[staceythinx]

Illustrations from Rachel Ignotofsky’s Women In Science series 

[lmaoatheist-deactivated20121230]

[aspiringdoctors-blog]

A classic.

DYING

[terrible-tentacle-theatre]

Clickbaiting level: National Geographic

[madsciences]

this added 5 years to my life

[sixpenceee]

A microbiological culture of an 8-Year old’s handprint after playing outside. This makes me… itchy.

[mysticaljay]

Cool af

[monochrome-in-madness]

@sixpenceee , I recently fell in love o-o

Portuguese man-of-war :

A floating colonial coelenterate with a number of polyps and a conspicuous float. It bears long tentacles which are able to inflict painful stings and occurs chiefly in warm seas.

[sixpenceee]

A graceful creature of the seafloor, a sea pen resembles a plump, old-fashioned quill pen. Its colors range from dark orange to yellow to white. Each sea pen is a colony of polyps (small anemonelike individuals) working together for the survival of the whole. (Source)

[scribebynight]

mermaid calligraphy

[scinerds]

Scientists Have Outlined an 8-Page Plan to Fix What's Wrong With Science

The time has come for bad science. An international team of researchers just released an eight-page

An international team of researchers just released an eight-page “manifesto” on how to improve the quality of scientific research, and it’s pretty heavy stuff.

In 2016, there was widespread concern among the scientific community that we’re now in the midst of a ‘reproducibility crisis’, meaning many results that are being published can’t be replicated - even when scientists repeat the exact same experiment. And today’s 'publish or perish’ research culture is only making the problem worse.

But the new document, “A manifesto for reproducible science”, suggests that there are ways that we can fix the flaws in the current scientific process, and save science before it evolves into something “shoddy and unreliable”.

[neurosciencestuff]

Synaptic connectivity motifs contribute to efficient memory storage and retrieval in hippocampus

Neuroscientists combine functional connectivity analysis and network modeling to investigate synaptic mechanisms of pattern completion in hippocampal CA3 network

The hippocampal CA3 region plays a key role in learning and memory. One of the most remarkable properties of the network is its ability to retrieve previously stored memories from incomplete or degraded versions, a phenomenon that is widely known as pattern completion. It is generally accepted that the synapses between CA3 pyramidal cells, the recurrent CA3–CA3 synapses, play a key role in pattern completion, but how this exactly works has remained enigmatic. In a recent research article entitled “Synaptic mechanisms of pattern completion in the hippocampal CA3 network”, published on September 9, 2016, in Science, Jose Guzman, Alois Schlögl, Michael Frotscher, and Peter Jonas have investigated these mechanisms by combining functional connectivity analysis and network modeling. Their findings suggest that the rules of synaptic connectivity between CA3 pyramidal cells contribute to the remarkable efficiency of pattern completion.

Previous theories of the hippocampal formation often depicted the CA3 region as a network of highly interconnected cells. The neuroscientists at the Institute of Science and Technology Austria (IST Austria) tested this hypothesis using a technique that allows monitoring the connection between electrical signals in up to eight neurons at the same time. Using this octuple recording technique, they made several highly surprising observations. First, they found that connectivity was sparse, with an average connection probability of approximately 1%. This massively challenges the dogma of a network of highly connected cells. Even more surprisingly, they discovered that connectivity in the network is not random, but exhibits connectivity motifs that occur much more frequently than expected for a random network. Thus, the structure of the hippocampal CA3 network may be somewhat reminiscent of a “small world” architecture as found in social networks. Finally, the authors revealed that synaptic connections between two cells are mediated by only one or two synaptic contacts. This is also remarkable because much higher numbers have been found for excitatory synaptic connections in the neocortex.

What could be the functional significance of these highly specific synaptic connectivity rules, in particular in relation to pattern completion? To address this question, Peter Jonas and his team built a model of the CA3 network that incorporates many of these new experimental observations. In contrast to many previous studies, the network was implemented in full size, so that all 330,000 CA3 neurons of the rat hippocampus were simulated. This modeling approach made heavy use of the computer cluster of IST Austria, and was strongly supported by the scientific service unit “scientific computing” of the institute. The authors found that a full-size network model with realistic connectivity of 1% was indeed able to perform the network computation of pattern completion. Furthermore, they discovered that the presence of connectivity motives increased, under certain conditions, the performance of the network. Finally, the design of synaptic connections based on one or two synaptic contacts also seems useful for pattern completion, apparently because it minimizes redundancy in the flow of information in the network. Thus, both macro- (e.g. motifs) and microconnectivity (e.g. properties of connection) facilitate pattern completion in the CA3 cell network. “The results provide a nice demonstration of how the Hopfield quote “build it, and you understand it” can be successfully applied to important questions in neuroscience,” says Peter Jonas, who leads the cellular neuroscience group.

[neurosciencestuff]

What Causes Déjà Vu?

You walk into a room and suddenly your brain goes fuzzy with an overwhelming wave of familiarity—although this is a totally new experience. Like something out of a sci-fi plot, it almost seems as if you’ve walked into the future.

Chances are, you’ve experienced this situation, known as déjà vu, during your life. Déjà vu (French for ‘already seen’) occurs in approximately 60 to 80 percent of people—a phenomenon that’s almost always fleeting and may manifest at any time. Despite wide-spread coverage, bursts of déjà vu are still misunderstood by the scientific community.

“Because there is no clear, identifiable stimulus that elicits a déjà vu experience (it is a retrospective report from an individual), it is very difficult to study déjà vu in a laboratory,” said Michelle Hook, Ph.D., assistant professor in the Department of Neuroscience and Experimental Therapeutics, at the Texas A&M Health Science Center College of Medicine.

A glitch in the brain?

“According to many studies, approximately two-thirds of individuals have experienced at least one episode of déjà vu in their life,” Hook said. “Understanding how memory storage works may shed some light on why some experience it more than others.”

Episodes of déjà vu may be closely related to how memory is stored in the brain. Retention of long-term memories, events and facts are stored in the temporal lobes, and, specific parts of the temporal lobe are also integral for the detection of familiarity, and the recognition of certain events. The takeaway: The temporal lobe is where you make and store your memories.

While déjà vu’s connection to the temporal lobe and memory retention is still relatively unknown, clues about the condition were derived from people who suffer from temporal lobe epilepsy (a condition in which nerve cell activity in the brain is disturbed—causing seizures). Findings suggest that déjà vu events may be caused by an electrical malfunction in the brain.

Epileptic seizures are characterized by dysfunctional neuron (nerve cell) activity across the brain which disrupts the electrical impulses that ‘fire’ neurons. These impulses can spread across the whole brain—inducing seizures. “

“Clinical reports published in Epilepsy Research and Treatment by researchers at the University of Leeds show that some patients who suffer from temporal lobe epilepsy report experiencing déjà vu, almost as a sort of warning, before an epileptic seizure event,” Hook said.

But, what is the basis for déjà vu in healthy people without epilepsy? Some researchers describe it as a ‘glitch’ in the brain—when the neurons for recognition and familiarity fire—allowing the brain to mistake the present for the past. In fact, the same abnormal electrical impulses that contribute to epilepsy can present in healthy people. An example of this is a hyponogogic jerk (an involuntary muscle spasm that occurs as a person is falling asleep).

Shortcuts in neural pathways

Instances of déjà vu in healthy individuals may also be attributed to a ‘mismatch’ in the brain’s neural pathways. This could be because the brain is constantly attempting to create whole perceptions of the world around us with limited input.

For example, it only takes a small amount of sensory information—like a familiar smell—for the brain to create a detailed recollection. Déjà vu could be linked to discrepancies in the memory systems of the brain, leading the sensory information to by-pass short-term memory and reach long-term memory instead. This may produce the unsettling feeling that we’ve experienced a new moment before.

In the visual system, sensory information travels through multiple pathways to the higher cortical centers of the brain (areas that play a key role in memory, attention, perception, awareness, thought, language and consciousness), with all information reaching those centers at or around the same time.

“Some suggest that when a difference in processing occurs along these pathways, the perception is disrupted and is experienced as two separate messages. The brain interprets the second version, through the slowed secondary pathway—as a separate perceptual experience—and thus the inappropriate feeling of familiarity (déjà vu) occurs,” Hook said.

According to Hook, there is still much to learn about déjà vu and the mechanisms behind it. “There may not be a simple answer for the mechanisms behind déjà vu yet, but, with further research and studies, conclusive evidence for the phenomenon may be discovered in the future,” she said. Wouldn’t that be like experiencing déjà vu all over again?

[iksplohr]

Video here

[prostheticknowledge]

3DMetrica

Designer Angel Quintana uses computational design tools Rinoceros and Grasshopper 3D to create algorithmic tattoos:

More Here

[khymeira]

Yes yes yes

[fuckyeahfluiddynamics]

Mixing cornstarch and water creates a fluid called oobleck that has some pretty bizarre properties. Oobleck is a shear-thickening, non-Newtonian fluid, which means its viscosity increases when you try to deform it with a shearing, or sliding, force. But as the Backyard Scientist demonstrates above, striking oobleck with a solid object produces some spectacular and very non-fluid-like results. The golf ball’s impact blows the oobleck into pieces that look more like solid chunks than liquid droplets. This solid-like behavior occurs because the impact jams the suspended cornstarch particles together, creating a solidification front that travels ahead of the golf ball. Imagine how a snow plow pushes a denser region of snow ahead of it as it drives; the cornstarch behaves similarly but only in a region near the impact. Once that impact force dissipates, the particles unjam and the mixture responds fluidly again. (Image credit: The Backyard Scientist, source; research credit: S. Waitukaitis and H. Jaeger, pdf)

[sixpenceee]

I found this gif while lurking on the web and oh my god, it took my breath away. It’s an inside look into Jupiter’s atmosphere as seen on Cosmos. It really makes you think about the vastness of what’s out there. This is so beautiful.

[tripintomylife]

Oh wow. This is pretty sweet

[sixpenceee]

It’s so awe-inspiring. 

[danieladiaz2170]

This is terrifying

[jollylollylily]

Beautiful and yet scary at the same time.

[sixpenceee]

The above is supposed to a good visual representation for an acid trip. I personally have never done LSD, but from the comment this seems to be a great representation. What do you guys think?

[sixpenceee]

Here are some responses for my post:

That’s pretty cool guys!

[bearprinceloverresurrected-blog]

A longer loop would give a better impression of visual sensations I experienced.  The landscape would “breath” and zoom (slightly) in where light was more intense and track with moving light.  But it’s pretty darn good, yeah.

[iamrobertomex115]

This is actually quite wild haha, great find

[sixpenceee]

Thanks!

[ri-science]

LEVITATING PUMPKINS!

“And the cursed pumpkin rose up from the earth, carried to the sky by the spirits of All Hallows’ Eve.” Or in other words, Andy put a superconductor in a pumpkin and levitated it on a magnetic track.

Watch the full video here!

[did-you-know]

I know, Halloween is done. But Ri Science did some pretty amazing things with pumpkins that I thought you needed to see. If the levitation wasn’t enough, here’s some more:

Exploring Pumpkins and Thermite

In the top pumpkin, the reaction between iron oxide (rust) and aluminium powder, set off by a strip of magnesium to provide enough heat, produces iron and aluminium oxide. 

The reaction is incredibly exothermic, occurring at about 2000 degrees Celsius. At this temperature, the iron melts and is spewed out in a rain of fire, and flows out as a river of molten metal into the poor head below. This is more than enough to set off the gun cotton in the second pumpkin, which bursts into a healthy fireball.

Guncotton in a Pumpkin… 

and the decomposition of hydrogen peroxide catalysed by potassium iodide.

[smithsonianlibrariesarchives]

It may still be a little early to head for the beach, but that won’t prevent us from thinking beachy thoughts.

Shells from Japanische Meeres-Conchylien T 2-3 , Cassel,T. Fischer,1869-1874.

[themedicalstate]

No Rest For Your Sleeping Brain

There’s new evidence that the brain’s activity during sleep isn’t random. And the findings could help explain why the brain consumes so much energy even when it appears to be resting.

“There is something that’s going on in a very structured manner during rest and during sleep,” says Stanford neurologist Dr. Josef Parvizi, “and that will, of course, require energy consumption.”

For a long time, scientists dismissed the brain’s electrical activity during rest and sleep as meaningless “noise.” But then studies using fMRI began to reveal patterns suggesting coordinated activity.

To take a closer look, Parvizi and a team of researchers studied three people awaiting surgery for epilepsy. These people spent several days with electrodes in their brains to help locate the source of their seizures. And that meant Parvizi’s team was able to monitor the activity of small groups of brain cells in real time.

“We wanted to know exactly what’s going on during rest,” Parvizi says, “and whether or not it reflects what went on during the daytime when the subject was not resting.”

In the study published online earlier this month in Neuron, the team first studied the volunteers while they were awake and answering simple questions like: Did you drive to work last week?

“In order to answer yes or no, you retrieve a lot of facts; you retrieve a lot of visualized memories,” Parvizi says.

As expected, the team saw activity in two widely separated brain areas known to be involved in episodic memories. And the activity was highly coordinated — suggesting the different brain regions were working together to answer the questions.

Next, the volunteers were allowed to rest and even go to sleep while the researchers continued to monitor signals from the two brain areas. And the signals from the two regions remained coordinated, as if they were still working together, Parvizi says.

“What we found,” he says, “was that the same nerve cells that were activated to retrieve memories … have a very coordinated pattern of noise.”

The brain may be working to maintain the relationship between regions that have cooperated recently, and may need to again, Parvizi says. This would help explain why the brain, unlike the body, consumes a lot of energy whether or not it has a specific job to do.

“Any brain is designed in such a way that it’s using a lot of energy at what we call a ‘resting state,’ ” Parvizi says. “So it’s not really a resting brain.”

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