Our divided brains are far more complex and remarkable than a left/right split

The notion that the brain’s right hemisphere is responsible for emotion and its left hemisphere is responsible for reason has been debunked. But the two hemispheres are indeed distinct, albeit in much more complex ways than we once thought. Animated by Cognitive Media with audio excerpted from a lecture given at the Royal Society of Arts (RSA) by the British psychiatrist Iain McGilchrist, The Divided Brain takes a deep dive into the real differences between our two brain hemispheres.

This video is published under the RSA open-access licence. For more information, visit the RSA website’s disclaimer and policies page.

The blob with a superpower: cut a flatworm in four pieces and watch it regenerate four-fold

Planarians are small flatworms that live in wet and humid areas around the globe. Although these creatures are relatively simple, their small, soft bodies possess one of the most amazing secrets in the animal kingdom. Cut a planarian into as many as 279 pieces and, within a few weeks, each bit will regenerate into a full new worm – head, eyes, digestive system and all. This incredible ability raises interesting questions for philosophers, who might wonder which, if any, of these worms is the ‘original’, and for medical researchers, who are hoping to harness the adaptability of planarian’s powerful regenerative stem cells to help regrow tissue, and potentially even limbs, on humans. Read more about this video at KQED Science.

Dance seems to be the ultimate frivolity. How did it become a human necessity?

Every culture dances. Moving our bodies to music is ubiquitous throughout human history and across the globe. So why is this ostensibly frivolous act so fundamental to being human? The answer, it seems, is in our need for social cohesion – that vital glue that keeps societies from breaking apart despite interpersonal differences. The French sociologist Émile Durkheim (1858-1917) theorised that ‘collective effervescence’ – moments in which people come together in some form of unifying, excitement-inducing activity – is at the root of what holds groups together. More recently, Bronwyn Tarr, an evolutionary biologist and psychologist at the University of Oxford who is also a dancer, has researched the evolutionary and neurological underpinnings of our innate tendency to bust a move. Drawing on the work of both Durkheim and Tarr, this Aeon Original video explores that unifying feeling of group ‘electricity’ that lifts us up when we’re enthralled by our favourite sports teams, participating in religious rituals, entranced by music – and, yes, dancing the night away.

Surgeons with chainsaws – the breathtaking craft of logging on a Swiss mountainside

In most of the world, logging is now largely the work of massive machinery. But in the steeply sloped woods above Lake Ägeri in Switzerland, a combination of chainsaws, jacks, muscles and gravity is still the most effective means of bringing down trees for lumber. Once every four years, skilled loggers travel to the area to collect mature trees in a sustainable harvesting tradition that, in turn, allows saplings to take in sunlight and flourish. After felling the trees at careful angles, the workers send them careening through the woods with spectacular speed and force until they reach the water below with a satisfying splash. From there, the timber is floated downriver into town. The loggers’ confident expertise masks the immense dangers of the job, which could easily turn deadly in an instant. With stunning cinematography, Ins holz (In the woods) offers a rare look at this nearly extinct practice and the culture that surrounds it, making for a deeply visceral and visually stunning celebration of a hard day’s work.

A meditative cinepoem from 1929 captures the reflective, ethereal wonders of water

The US photographer and filmmaker Ralph Steiner (1899-1986) is widely considered to be a pioneer of both media, celebrated for his century-spanning work in modernist photography and documentary and avant-garde film. H₂O (1929), his debut short and one of the earliest US art films, is a meditative, visual ode to water in its many forms, focused on the liquid’s various textures and shape-distorting reflective qualities. In a series of static yet dynamic shots, water-spewing pipes and fire hydrants, waterfalls, raindrops, slow-flowing streams, and the shimmering surfaces of near-stagnant bodies appear on screen, with the visuals gradually becoming more abstract as Steiner transitions to closeups of water surfaces. This version of the film features a new original piano score from the Illinois-based composer William Pearson, commissioned by Aeon. H₂O is frequently mentioned alongside another documentary touchstone of the same year: Regen, by the Dutch directors Joris Ivens and Mannus Franken, which celebrates Amsterdam in the rain.