By Emma Meyers
Neuroscientists these days know a lot about how we see things. They know that when you look at an object, the visual information that enters your brain through your eyes must go through many hierarchical levels of processing in order to go from light waves to electrical impulses to green coffee cup. They know that during the early stages of this processing in the primary visual cortex (V1), visual information’s first cortical stop for decoding, our brains’ representations of objects are coarse, yet-unidentified conglomerations of edges, luminance, shadow, and color.
What they don’t know, though, is how motion contributes to the rough picture starting to come together in V1.
About a year ago, neuroscientists of UC Berkeley came up with a solution to this problem. Using functional magnetic resonance imaging (fMRI), a technique that detects which areas of the brain are most active, they looked at the brains of subjects watching movies and, through complex computations, were able to reconstruct models of what moving images might look like at the V1 level of processing.
This is what they found:
Pretty cool, huh?
In order to build these reconstructions, Professor Jack Gallant and his colleagues recorded the brain activity of subjects watching movies in an fMRI scanner and developed an algorithm for reconstruction, a sort of “key” or “dictionary” that could be used to translate the raw data from the fMRI into moving images. The subjects were then shown more movie clips, this time to test the reconstruction algorithm. The result is the video above. As we might expect from the V1 level, the images are coarse and rely heavily on edges, color, and contrast between light and shadow to create objects, but they’re surprisingly similar to the original clips.
Excited about their findings, the Berkeley group suggests that their new technology could one day allow us to watch our own dreams to see into the minds of coma patients. Until then, though, we’re a step closer to understanding how we process the world we move through every day.
You can read the full report of this study here, or watch an interesting video of the scientists explaining their work here.
By Ian MacArthur
Anyone who has ever suffered from the common cold understands the nuisance posed by mucous buildup in the upper respiratory tract. Although it may cause discomfort, mucous plays an important role in the body’s defense by trapping pathogens that seek access to tissues and then excreting them by way of a sneeze or cough. While the seasonal stuffy nose or sinus infection caused by mucous buildup is unwelcomed by all, these conditions become particularly critical for patients of cystic fibrosis, a genetic disorder characterized by the abnormal production of mucous that blocks respiratory, digestive, and reproductive tracts.
Cystic fibrosis (CF) is caused by a mutation to the CFTR gene located on chromosome 7. Short for cystic fibrosis trans-membrane conductance regulator, CFTR codes for a chloride ion channel protein responsible for the transport of chloride ions into and out of epithelial tissues. Additionally, CFTR is responsible for the regulation of sodium ion channels that are important in the function of the pancreas and lungs. The deletion of the three nucleotide codon for the amino acid phenylalanine inhibits the function of the CFTR protein in about 70% of CF cases, although over 1,000 different mutations have been identified. The dysfunctional CFTR protein is unable to properly regulate the ionic concentrations of cells that produce sweat, saliva, and mucous. Because chloride and sodium ion concentrations are essential for the proper flow of water in these tissues, mucous secretions are not properly hydrated, causing them to be thick and sticky.
The thick secretions of mucous have disastrous effects on the bodies of CF patients. Mucous buildup in the lungs can block air passageways, making breathing difficult and leaving patients prone to potentially fatal bacterial infections. Additionally, mucous may block passages in the pancreas that may lead to severe digestive problems, as well as reproductive ducts that often cause infertility. Recurrent cases of pneumonia are associated with the respiratory effects of CF, in addition to fatigue and constant coughing and sinus blockages.
Cases of cystic fibrosis can be found in all ethnic groups, although the illness has the highest incidence among Caucasians in the United States, specifically those ancestrally hailing from Northern and Central Europe. CF is inherited recessively, and consequently millions of people carry the gene for the disorder without ever developing symptoms. It is estimated that nearly 1 in 30 Caucasians in the United States is a carrier of a mutated CFTR gene, and that the disease currently affects approximately 30,000 Americans.
Although there is currently no cure for cystic fibrosis, a number of treatments exist that help patients effectively cope with symptoms. Antibiotics are administered to cure sinus infections and to treat bacterial pneumonia, and mucous can be removed periodically from the respiratory tracts of patients via suction and other methods. A specialized diet is required to counteract digestive problems that may arise, and vitamin and enzyme supplements can also aid in this capacity. The average life expectancy of CF patients is between thirty to forty years, with death commonly caused by respiratory problems. Though this may appear a grim prognosis, most patients are able to lead healthy lives well into adulthood, and increased life expectancy for patients over time demonstrates progress in treating the disease. As our proficiency in treating the illness advances, it is possible that someday the condition need not bound the lives of CF patients.
By Alexander Bernstein
First identified in China in November 2002, the Severe Acute Respiratory Syndrome (SARS) virus seemed to be the thing of science fiction and nightmares. The disease spread within months, consumed much of the world, and included relatively high percentage (around 10%) of fatal cases, with a frightening over 50% mortality rate for those over the age of 65. The outbreak of SARS between November 2002 and July 2003 was perhaps the closest any virus has come to full blown pandemic status in recent history. Frighteningly, early symptoms are virtually indistinguishable from regular strains of influenza, which, by comparison, only has a fatality rate of 0.03%. Perhaps the only sign of a more serious infection is the greater than 38° C temperature that appears to be conserved among all cases.
Believed to have originally come from Palm Civets in China, the SARS causing agent is a type of coronavirus that had been undiscovered prior to the outbreak. Despite the lack of a particularly successful treatment for this positive stranded enveloped RNA virus, a swift international medical response, marked by successful quarantines and testing, helped stop the epidemic and prevent further spread. As such, it had been believed that the disease was all but non-existent.
Unfortunately this may no longer be the case. According to the Huffington Post, as of a November 30th, an unknown Respiratory virus has infected at least nine people in the middle east, with the majority of cases in the country of Jordan. An unusually high number of these cases (five) have been fatal. The overall atmosphere regarding this outbreak has been extremely tentative as World Health Organization (WHO) spokesman Gregory Hartl concedes that the nature of transmission has yet to be determined: “It’s too early to say whether human-to-human transmission occurred or not, but we certainly can’t rule it out.” Furthermore, experts are fearful that many of the afflicted do not appear to have come in contact with animals, suggesting a human-to-human spread. With late symptoms including high fever and pneumonia among other serious respiratory problems, the resemblance to SARS cannot be ignored. An unexplained 11 person pneumonia outbreak in a hospital in Zarqa, Jordan, just outside the country’s capital is also troubling and may suggest a new coronavirus as the likely culprit. This cluster of infections raises further concerns, as a contagion among caregivers is typically indicative of a virus that can easily spread among humans. Alarmingly, WHO suspicions maintain that the new coronavirus is likely not limited to only the specific area where patients have tested positive as The Scientific American’s Helen Branswell reports, “WHO is convinced that whatever the source of the virus is, it is probably not unique to those countries.” Although such a suggestion is not reassuring, the fact the spread of the virus at least for now appears to be limited to clusters in Jordan an Saudi Arabia allows for the optimistic interpretation that this particular coronavirus does not spread as easily among humans as did its cousin responsible for SARS. Regardless, the situation warrants attention and close monitoring.
By Nate Posey
With the election season well and truly over, Americans can now focus their full attention on the looming national crisis: the potential disappearance of Hostess Twinkies. Yes, the fate of the world’s food supply has never seemed bleaker, but the gathering storm goes well beyond the possible loss of the greatest cream-filled concoctions of all time. According to the World Health Organization, the global population is expected to surpass nine billion by the year 2050 before finally leveling off, and those additional hungry mouths will require an over thirty percent increase in total food production. Of course, you are quite right to be skeptical of any doomsayers on the topic of global starvation; the record of failed predictions of an impending and catastrophic food shortage dates all the way back to antiquity. Even as recently as 1968, Stanford Professor Paul Ehrlich predicted that the world’s burgeoning population would result in massive starvation and widespread loss of life throughout the 1970’s and 80’s, a disaster whose conspicuous failure to materialize coincided with a rather nasty decline in Ehrlich’s book sales.
Ehrlich, like most other would-be prognosticators of the last few centuries, based his estimates on the reasoning of British demographer Thomas Malthus, who claimed that the geometric growth of human population would inevitably overtake the comparatively linear growth of agricultural production. As hindsight has abundantly shown, such naïve modeling has failed to sufficiently account for the expanding role of technology in agriculture as well as the various socioeconomic forces that have substantially mitigated population growth. However, the concern this time around stems from a new factor in the equation: climate change. A study organized by the United Kingdom’s Government Office of Science concluded that the depletion of aquifers and other freshwater reserves coupled with the increasing volatility of climate and weather conditions poses a very real threat to the world’s food production capacity in the coming decades. The current drought in the United States, the most widespread in twenty-five years which has impacted nearly 70% of both crop and livestock production, serves as a rather poignant harbinger for the coming difficulties.
So, what is the solution? Unfortunately, the answers to be found in science fiction are none too inspiring. The citizens of the last remaining human city in The Matrix by the Wachowskis overcome the complete lack of arable land in their post-apocalyptic hellscape by concocting a fabricated brew of “single cell protein combined with synthetic aminos, vitamins, and minerals.” The Mycogenians in Isaac Asimov’s Prelude to Foundation turn to an equally stomach-churning dependence on cultivated yeasts and algae laced with synthesized flavors. But the grand prize for the least appetizing future cuisine goes handily to Soylent Green from Richard Fleischer’s 1973 movie of the same name. Faced with an eerily similar scenario of a runaway greenhouse effect and an exploding population, the citizens of Fleischer’s dystopia subsist almost entirely on the processed green squares from the colossal Soylent corporation. What at first brush appears a pathetically bland menu becomes positively horrifying when the truth about the squares’ ingredients comes out, a revelation which shall be forever immortalized by the frantic shouts of Charlton Heston in the film’s closing minutes: “Soylent Green is people!!” (I would apologize for the spoiler, but I’m pretty sure the statute of limitations has expired for this classic sci-fi thriller).
While industrially-scaled cannibalism seems like a stretch for 2022 (the date in Fleischer’s movie), the next several decades will assuredly lead to surprising developments in the human race’s long history with food. For example, a team of biologists at the University of Maastricht is currently attempting to grow enough beef for a hamburger in vitro, an enterprise with tremendous implications in the ethical debates on animal consumption. Such an endeavor reflects the growing significance of genetic modification in agriculture that, while certainly no cure-all for the multifarious challenges of the coming century, holds considerable promise for improving both yield and efficiency. As for me, I’m actually quite excited to see what’s cooked up in our lab-kitchens of the future; I just hope I’ll never have to give up the Jenny Craig program…