Jacobs J. et al. Direct recordings of grid-like neuronal activity in human spatial navigation. Nature Neuroscience, 2013

Do you happen to have a poor sense of direction? Do you often find yourself holding a map upside-down? Well, now you can blame your grid cells. Using direct human brain recordings, researchers have identified a novel type of cell in the brain that helps people keep track of their relative location while navigating through an unfamiliar environment. Scientists got this rare opportunity to identify these unique cells while they studied brain recordings of epilepsy patients via electrodes implanted deep inside their brains. These cells have been called “grid cells” because they are activated in a triangular grid pattern. The “grid cell” is distinct among brain cells because its activation represents multiple spatial locations, which allows the brain to keep track of navigational cues, such as how far you are from a starting point or your last turn. This type of navigation is called path integration. During brain recordings, 14 study participants were asked to play a video game where they ride a virtual bicycle to navigate from one point to another to retrieve objects and then recall how to get back to the places where they found the objects. While participants were playing the game, researchers examined the relation between navigation and the corresponding activity of individual neurons. Results were striking: each grid cell responded at multiple spatial locations that were arranged in the shape of a grid suggesting that the navigation information is principally encoded in our brains through this triangular grid pattern. Without grid cells, humans would frequently get lost or have to navigate based solely on landmarks. Differences in how well the grid cells work could potentially explain why some people have a better sense of direction than others. In addition, grid cells are located in the entorhinal cortex which is a critical component of human memory. The entorhinal cortex is also the first brain region affected in Alzheimer’s disease. Thus, understanding how grid cells work could potentially help us to understand why people with Alzheimer’s frequently become disoriented as well as to develop new strategies to improve brain function in the affected individuals.

Giant viruses open Pandora’s box

Philippe N. et al. Pandoraviruses: amoeba viruses with genomes up to 2.5 Mb reaching that of parasitic eukaryotes. Science, 2013 Jul 19

On a fairly ordinary day, two French biologists were analyzing water samples collected off the coast of Chile. What they saw under the microscope was quite amazing: a previously unidentified organism, about the size of a bacterial cell, appeared as a large dark spot. Astonishingly, these new organisms seemed to be infecting and killing the amoeba in the water. Later, another group of researchers found a similar organism in a pond in Australia. Both groups soon realized that they discovered a type of “giant” virus which is at least twice as big as the largest known viruses. The biggest virus discovered so far was called Mimiviruses, with a size of 700 nanometers and carrying more than 1000 genes. The newly discovered viruses are called Pandoraviruses, which are 1 micrometer long and 0.5 micrometers across. Pandoraviruses are visible under a light microscope and contain more than 2500 genes. A viral genome consisting of 2500 genes is extremely large compared to known viruses, such as the Influenza or HIV, which only contain 10 genes or less. More importantly, 93% of the genes did not resemble any known lineage in the natural world, suggesting Pandoraviruses are not related to any known virus family and may represent a new life form. These findings generated new perspectives about how scientists see viruses. It raised the possibility that there might be many different kinds of giant viruses out there to be discovered. Some biological features in these giant viruses could easily blur the line between life forms and viruses, which are considered to be non-living. Although Pandoraviruses do not infect human cells, there might be other giant viruses out there that could infect human cells. There are still a lot of human diseases known to have an infectious component but for which no infectious agent has been identified yet. This study will definitely encourage people to actively look for the role of giant viruses in some diseases.

See through the Ears

Haigh A. et al. How well do you see what you hear? The acuity of visual-to-auditory sensory substitution. Frontiers in Psychology, 2013 Jun 18

Scientists have created a revolutionary device for the blind that allows them see the world through their ears. The device “vOICe” trains the brain to invoke mental images of what they are hearing around them. The first test trial of vOICe has been performed on blindfolded sighted people. The participants took a standard eye test where they were asked to view the letter E turned in four directions and in various sizes. The best visual acuity is considered 20/20 (distance in feet/size of the E) and the majority of participants were able to achieve the best performance possible, nearly 20/400 sight. This is an impressive result when compared to an alternative stem-cell based sight restoration technique, which only yielded 20/800 visual acuity. In addition, the affordable and non-invasive nature of vOICe would offer a unique option. But, how might this work in practice? One can imagine that visually-impaired people would wear a discreet head-mounted camera such as Google Glass and receive wireless audio information through mini earbuds. As the person turns to look in various directions, the device scans images and correlates those with soundscapes, then the person’s brain would momentarily translate those into mental images of the objects — like braille for the ears. These sensory substitution devices could potentially be employed in combination with other alternative invasive techniques to train the brain to see again, or even to see for the first time.

It was around dawn, and the day was not yet fully light. Rain the night before had left a thick cloud covering the scene. The music of bugs and the chanting of birds filled the air. Against a background of a slight breeze, which provided a smooth and continuous whistle, consecutive, rhythmic thumps could be heard. These thumps were the sounds of a giant’s footsteps as he was walking to work early in the morning.

Meanwhile, my grandpa and his friends were enjoying the water on the walkway. But a hot day was soon going to make the walkway the death bed of many of his friends. Aside from the heat of the day, the footsteps of the giants would bring to an end the lives of many others. Neither he nor his friends were aware of any of this. They were simply enjoying their water on the walkway.

That morning, the giant who was walking to work bent down towards my grandfather, grabbed a thin stick from the ground, and tried to kill him. Not ready for such an attack in the midst of his breakfast, my grandfather was stupefied, did not know what to do. He just spiraled away to escape the giant’s attack, as we always do in case of danger. But all was in vain; the giant would not give up.

Finally, the giant accomplished what he was trying to do, and thus my grandfather was saved from both the heat and the giant footsteps. It turned out that my grandpa had misunderstood the giant. Normally, other giants would walk on us, or would ignore us, and this giant was the same; or so he had thought. However, this one was trying to put the stick under my grandpa to lift him and place him onto the soil where he could be safe. My grandpa said that he appreciated this help more later when he heard his friends dying on that same walkway.

The story of a giant who was unlike others spread from the family to friends, and became known all around. The world underground rejoiced at the existence of this one giant who was not like others… Maybe there were other giants like him, too; and the underground world kept praying for those giants that they might be protected from things they were unaware of, just as that giant had saved my grandfather from things that he was unaware of.

After my grandfather’s times, his story became a nostalgic tale for the elders and a bedtime story for little ones. The world aboveground became worse than the world underground. Instead of long trees above with their roots under ground, you would see huge, tall rocks in both places. The rocks underground provided water to everyone, but the rocks aboveground only provided water to the giants. The roots of the plants and trees used the marrow of the earth to embellish it, but the long channels that the giants sank into the ground were like huge veins draining the earth to death. We ceased praying for them.

One day, we heard screaming among the giants about an asteroid heading directly towards the earth. The only thing they were worried about was the end of their own lives. We were not surprised by this selfish reaction to that event because of their selfish past on the earth. And the asteroid came…

It was foggy again, but not due to clouds; it was quite dark, but not due to dawn. The fog and the darkness were due to dust spread over the face of the earth. We were fortunate to be able to sustain our lives under such harsh conditions. As for the giants, they were not suffering much from the conditions, as they had taken shelter in special chambers built only for them. Being some of the few survivors of the impact, we were of significant use to them. After using the entire earth selfishly, now they were enslaving us. So, they still lacked our prayers for their protection. Could they ever figure out, despite their hardened hearts, why such tragedy had befallen them?

Not long after that time, we witnessed something totally incredible. One of the giants came out of the protection chambers to do something that was completely unexpected. He looked through his goggles at the sky and tried to take a deep breath. As he was coughing because of the dust in the air, he opened the nylon bag he was carrying. He sat on the ground, dug a hole with his hands, and uncovered the thing in the bag: a daisy plant. Was he going to plant it? But why? The chances of its survival were almost none. What benefit would it bring him, anyway, even if it survived for a day? He looked pleased with what he was doing. He even smiled at a worm that was escaping the hole he had dug for the flower. What was going on in his mind?

It was just at the moment he was about to plant the flower that the earth suddenly started shaking like crazy. The planet was dying because of the deep cracks caused by the impact of the asteroid. Now, neither the giant nor the flower had any chance of survival. He did not know what to do for a while; then he started shedding tears: “Oh my God! Oh my God!”

Then he saw the deep cracks forming near him, shaking and growing. It was as if the planet had started shouting at him in thousands of voices. He could not stand the quakes and fell down next to the hole, as if it were he, instead of the flower, that was going to be buried in it. At that moment, this giant was no different from us: lying on the ground, and seeking his way out of this doom. Who was there to help him? His cries were now screams: “Oh my God! Oh my God!”

All of a sudden, he stopped crying and started talking to someone, but we could not see anybody around: “Please, hold me tight. Do not leave me….” He continued, “But I can’t… I can’t….” Then, he tried to reach the flower that had rolled away from him when he fell down. He grabbed it and cradled it at his chest; but struck by a stone falling from one of the nearby rocks, he fell unconscious. As he was sinking into the growing cracks, we uttered a prayer for a giant who had planted a flower in his heart… The last prayer of worms, the last prayer for giants…

Seth Mette has a PhD in Aerospace Engineering and is currently working as a postdoctoral fellow at West Virginia University. He has a special interest in psychological fiction.

South-east Asia was hit by such a giant wave just before the New Year. A calamity that was fatal; an earthquake followed by a tsunami that abated only after leaving behind a death toll of 300,000. Like all past calamities, this tsunami also brought to doubting minds suspicions that lead to a denial of the existence of All-Merciful God. “A Nursi Reader” provides insights for us on how to approach disasters and events that are apparently “evil,” basing the argument on a critical question: is the creation of evil evil?

Perhaps in a disaster in which people can do nothing but surrender to their imminent destiny; but at other troubled times there is only one bosom upon which we can rest our heads-that of our mother. A man came to Prophet Muhammad, peace and blessings be upon him, and said, “O the Messenger of God! Who is more entitled to be treated with the best companionship by me?” The Prophet said, “Your mother.” The man said. “Who is next?” The Prophet said, “Your mother.” The man further said, “Who is next?” The Prophet said, “Your mother.” The man asked for the fourth time, “Who is next?” The Prophet said, “Your father.”

In another tradition the Prophet is reported to have said, “God has forbidden you to be undutiful to your mothers, to withhold (what you should give) or demand (what you do not deserve), and to bury your daughters alive. And God has disliked that you talk too much about others, ask too many questions (in religion), or waste your property.” As clearly seen in the tradition the Prophet lists improper manners to our mothers along with such atrocities as “burying daughters alive.” The lead article in this issue is a reference for us to frequently turn to in order to appreciate and re-appreciate the value of our mothers.

Full of mysteries, joys, and sorrows, life for humanity starts in the wombs of our mothers (this alone should suffice for the lifetime of thanks that we need to offer to them). But when exactly does life start for a yet unborn baby? Olgun Hasgul presents a comprehensive embryological study, guided by Qur’anic teaching in “Ensoulment: When Does Human Life Begin?”