Neurophilosophy

Archives for October, 2008

Halloween netsuke

Netsuke are miniature Japanese sculptures which are most often carved from ivory or wood, and sometimes from other materials. They were first made in the early 17th century, and used to fasten a small box (the inro) containing medicines and personal belongings to the sash (or obi) worn around traditional Japanese garments such as the…

An eye-opening view of visual development

The pioneering experiments performed by Hubel and Weisel in the late 1950s and early 60s taught us much about the development of the visual system. We now know, for example, that neurons in the visual cortex are organized into alternating ocular dominance columns which receive inputs from either the left or right eye and that…

First case study of developmental phonagnosia

The term phonagnosia refers to an inablity to recognize familiar voices or to discriminate between unfamiliar ones. This is a rare condition that is usually associated with brain damage: the ability to recognize familiar voices is impaired by damage to several regions of the right parietal lobe, and impaired voice discrimination is associated with damage…

Metaphysical self-trepanation

Artist Madeline von Foerster provides some insight into her extraordinary self portrait (above), in a comment posted on my article about trepanation: During a previous period of depression in my life, I often experienced a severe sensation of pressure in my cranium. It sometimes felt so unbearable I wished I had a hole in my…

Erasing memories

Erasing memories has long been a popular plot device for Hollywood scriptwriters. In the 2004 film Eternal Sunshine of the Spotless Mind, for example, Jim Carrey and Kate Winslet play a separated couple who undergo a radical treatment in order to abolish every trace of the relationship from their brains. The ability to erase memories…

The brain keeps time with a metronome

The fourth dimension – time – is essential for many cognitive processes, and for rhythmic movements such as walking. Recent research has begun to elucidate how neuronal activity encodes events that occur on the timescale of tens to hundredths of milliseconds (hundredths of a second) and contain cues which are required for processes such as…

The staggering escape of the crayfish

When confronted with threatening stimuli and predators, the crayfish responds with an innate escape machanism called the startle reflex. Also known as tailflipping, this stereotyped behaviour involves rapid flexions of the abdominal muscles which produce powerful swimming strokes that thrust the small crustacean through the water and away from danger. In the struggle for existence,…

Researchers from the University of Washington have demonstrated that paralysed monkeys can move using a simple neuroprosthesis consisting of an external electrical circuit which connects individual neurons in the motor cortex to muscles in the arm. Similar prostheses have been used to move external devices such as a robotic arm, but they required sophisticated algorithms…

Brain immediately recognizes transplanted hand

When David Savage was 19 years old, his right hand was crushed in a metal-stamping machine and subsequently amputated at the wrist by doctors. Afterwards, Savage was fitted with a mechanical cable-hook prosthesis, which he wore until December, 2006, when he became the third American recipient of a hand transplant from a cadaver donor (above).…

Silver nanorod microscopy

Japanese researchers have developed a design concept for a light microscope which could in principle be used for imaging of nanoscale objects. The device would rely on a novel subwavelength imaging technique which allows for the visualization of objects that are smaller than the wavelength of the photons used in the device. Once thought to…