Posts from the ‘neuroscience’ Category

To reflect the ongoing structural changes in the adolescent and twenty-something brain, many journalists and scientists use words and phrases like “unfinished,” “work in progress,” “under construction” and “half-baked.” Such language implies that the brain eventually reaches a kind of ideal state when it is “done.” But there is no final, optimal state. The human brain is not a soufflé that gradually expands over time and finally finishes baking at age 30. Yes, we can identify and label periods of dramatic development—or windows of heightened plasticity—but that should not eclipse the fact that brain changes throughout life.


Whether we can, at this moment in time, meaningfully link this life stage to neuroscience seems a tenuous proposition at best. By itself, brain biology does not dictate who we are. The members of any one age group are not reducible to a few distinguishing structural changes in the brain. Ultimately, the fact that a twenty-something has weaker bridges between various brain regions than someone in their thirties is not hugely important—it’s just one aspect of a far more complex identity.

The Neuroscience of 20-Somethings by Scientific American’s Ferris Jabr (via explore-blog)

As with most things related to the human condition, it is nearly impossible to describe it with one or two words. The brain, an incredibly complex organic computer, can certainly not be summed up by “half baked” at any stage.


All vertebrates’ eyes emerge from a single group of cells, called the eye field, located in the middle of the brain. The eye field cells evaginate to form two optic vesicles, which eventually give rise to two retinas, one on either side of the brain.

Eyes Emerge

Top image: In a ~5 somites embryo, eye field cells are stained red, and forebrain cells are outlined in green (upper left). A few hours later, in a ~10 somites embryo, the eye field (green) separates into two optic vesicles. At the same embryonic stage, the dorsal telencephalon, which sits atop the evaginating eyes, is labeled blue (bottom left). In both of these images, a midline positioned cross outlines the apical surface of the optic vesicles and the ventricular space. The animation follows the development of this same surface as the eyes emerge from the brain.

Sunrise in the Eye

Bottom image: Once the basic shape of the eye is specified, cells within the optic cup differentiate, populating the retina with neurons that sense light and refine the visual information before it is transmitted to the brain. In fish and amphibia, retinal stem cells are maintained throughout the animal’s lifetime in a stem cell niche located adjacent to the lens (yellow). Here in situ hybridization of a zebrafish eye (from a ~ 3-day-old larva) reveals gene expression patterns that distinguish retinal stem cells (red) from the cells that are becoming neurons (purple). By comparing gene expression patterns within the retinal stem cell niche in normal and mutant eyes, we gain insight into how stem cells turn into neurons.

Eyes are not only amazingly complex, but are reducibly so!


The Science of Linguistics

Linguistics is by definition the scientific study of language, but it’s been long debated whether it is a “soft” science. Science is the systematic study of the physical and natural world through observation and experiment, and hard sciences are generally perceived as more rigorous and accurate—i.e., natural, physical and computing sciences. “Soft” sciences are usually social, but linguistics seems to blur the line between the two—language is a social construct, but it’s also a complex, ever-evolving natural phenomenon, made up of dozens of sounds that combine to create thousands of words in thousands of different languages. Linguists study the use of language almost like animal behaviour is studied, and in recent years, modern linguistics has gravitated towards a “hard” science approach, focusing on accuracy, objectivity, and empirical data. Its many specialised subfields help enforce the rigour, such as phonology (the study of sound), syntax (the study of sentences), and semantics (the study of meaning), and linguistics also crosses disciplines to study the psychology, the neuroscience, and even the computer science of languageenabling the creation of language databases to analyse written and spoken patterns. However, hard sciences also have the capability to draw strong conclusions and make accurate predictions, and linguistics often deals with too many non-quantifiable variables to achieve either of these. For now, linguistics remains a soft science—but that doesn’t make it any less fascinating. After all, without language, we wouldn’t be able to communicate scientific ideas at all.

(Image Credit: 1, 2)

I only have some historical background knowledge on linguistics, mostly on how it shows human migrations, but the entire field seems fantastically interesting.

Life for the winner is more glorious. It enters the next round of competition with already elevated testosterone levels, and this androgenic priming gives it an edge that increases its chances of winning yet again. Though this process an animal can be drawn into a positive-feedback loop, in which victory leads to raised testosterone levels which in turn leads to further victory.

The science of “the winner effect” and why success breeds more success. (via explore-blog)


Retinal Fireworks

Retinal ganglion cells transmit signals from the rods and cones in the eye to the brain. The retinal ganglion cells shown here have the extraordinary property that their dendrites all point in a single direction. Remarkably, these neurons respond best to objects moving in the direction that the cells “point.”

In this particular image, a mouse retina is seen with “J” retinal ganglion cells marked by the expression of a fluorescent protein. Of course, in real eyes it’s not that simple – the millions of other neurons that these are entangled with are not marked, and thus appear invisible. The image was obtained with a confocal scanning microscope, and pseudocoloured.

Part of the Cell Picture Show’s amazing Brainbow series.



Blueprint for the Brain – 6-minute film by PBS and the Public Library of Science explores how the three-pound lump of jelly inside our skulls enables us to do everything that makes us human, and how scientists are now beginning to decipher the architecture of the brain and its secret lives.

( The Atlantic)

We are at once both more, and no more, than that three pound lump. And therein lies the beauty of the brain.


Neuroscientist David Eagleman, author of the excellent Incognito: The Secret Lives of the Brain, explains the curious neurological wire-crossing of synesthesia. Complement with a synesthetic person’s first-hand account of the experience.

It seems today’s Tumblr theme is synesthesia. No complaints!