Neurophilosophy

Archives for November, 2007

A novel axon guidance mechanism

[Introduction|Part 3|Part 4] Lopez-Bendito et al (2006) show that pathfinding of thalamocortical axons (TCAs) requires the formation of a permissive corridor through non-permissive territory, and that this corridor is generated by cells which undergo a tangential migration from the lateral ganglionic eminence (LGE). TCAs arise in the dorsal thalamus, and follow a stereotyped pathway into…

The growth cone

Dylan T. Burnette/ Nikon Small World.  The remarkable specificity of neuronal connectivity depends on accurate axon pathfinding during development. Pathfinding involves the detection of guidance cues in the environment by the growth cone, a motile chemotactic structure at the leading tip of the extending axon. The growth cone was discovered over 100 years ago by…

A short holiday

I’m off to Egypt later on today to attend my cousin’s wedding. I probably won’t have access to the internet for the 8 days that I’m there, so I’ve scheduled some posts for next week: the essay I’ve just submitted for my Masters will be appearing in a series of four posts, starting on Monday.…

A clockwork beetle

In his Insect Lab Studio, sculptor Mike Libby customizes real insects with parts from antique pocketwatches and electronic components from old circuit boards. Here, he describes how the idea first came to him: One day I found a dead intact beetle. I then located an old wristwatch, thinking of how the beetle also operated and…

Synaesthesia: The hidden sense

Synaesthesia is a condition in which stimuli of one type evoke sensations in another sensory modality. For example, hearing particular sounds might evoke strong sensations of colour or (more rarely) words might evoke strong tastes in the mouth. In The Hidden Sense, social scientist Cretien van Crampen investigates synaesthesia from an artisitic and scientific perspective.…

Speech prosthesis

At the Society for Neuroscience meeting in San Diego last week, a group of researchers presented data on a speech prosthesis which they say could soon enable a paralyzed man to talk again. The device, which consists of 3 gold recording wires, was implanted into the brain of Eric Ramsey, who was completely paralyzed in…

The toad is in custody

From KMBC: Clay County sheriff’s deputies said David Theiss, of Kansas City, possessed a Colorado River toad with the intention of using it as a hallucinogenic. Experts said it’s possible to lick the toad’s venom glands to achieve psychedelic effects. Most pet stores don’t sell the Colorado River toad because the venom can sicken humans…

The collective brain

An individual ant is quite insignificant, but a large group of ants can do quite remarkable things. Likewise, neurons evolved to communicate with each other, and are quite useless except when connected to a network of other neurons. I’ve always liked to use the ant colony as an anology for brain function. According to this…

Regular readers will know that I rarely write about politics. But this post is an exception, as it is written in memory of my father, who died on this day 7 years ago. That’s my father on the left, with the Palestinian leader Yasser Arafat, who died almost exactly four years later.

Proverbial psychology

Today’s Independent contains an extract from Taking the Proverbial, a book about the psychology of proverbs by Geoff Rolls. The extract includes sections from the book which discuss the proverbs “An elephant never forgets” and “Practice makes perfect”. The section about the first includes a nice summary of some animal cognition studies, and the second…