#stereotaxis

Wittgenstein was always disgusted with what he had said and with himself. Often he would rush off to a cinema immediately after the class ended. I mean, if even Wittgenstein might feel such a way. Then off to the movies, which he equates to dreams, incoming Freud. In the anecdote, we feel a fierce anxiety that moves him relentlessly to flee the scene, where the words he has just uttered linger in…

The research shows that people with Alzheimer's, Parkinson's and several other neurodegenerative conditions often experience sleep disturbances many decades before any symptoms appear, and that these disturbances are somehow linked to disruptions of the circadian rhythm. They include common sleeping difficulties such as insomnia, sleep apnoea, and daytime drowsiness, and some slightly more unusual ones. According to one small study published in 2011, for example, the early stages of Parkinson's disease are characterised by alterations in the content of dreams, particularly the presence of animals and increased aggressiveness.

Our system uses c-fos-tTA transgenic mice, in which the promoter of the c-fos gene drives the expression of the tetracycline transactivator (tTA) to induce expression of a gene of interest downstream of the tetracycline-responsive element (TRE) (8–12). We injected an adeno-associated virus (AAV) encoding TRE-ChR2-mCherry into the DG or CA1 of c-fos-tTA animals (Fig. 1A). Channelrhodopsin-2 (ChR2)–mCherry expression was completely absent in the DG of animals that had been raised with doxycycline (Dox) in the diet (on Dox) (Fig. 1B). Exploration of a novel context under the condition of Dox withdrawal (off Dox) elicited an increase in ChR2-mCherry expression (Fig. 1C). We confirmed the functionality of the expressed ChR2-mCherry by recording light-induced spikes in cells expressing ChR2-mCherry from both acute hippocampal slices and in anaesthetized animals (Fig. 1, D to F). Furthermore, optical stimulation of ChR2-mCherry–expressing DG cells induced cFos expression throughout the anterior-posterior axis of the DG (fig. S1, A to I).

In other words, we use our noses to smell food after it’s inside us, as well as before. But, in a fascinating snippet of news based on a presentation given yesterday at the American Chemical Society’s annual meeting by German food chemist Dr. Peter Schieberle, it seems that our noses may not be not alone in that ability, and that other cells in our bodies are able to “smell” food too. (##)

Cells themselves will move toward volatile organic compounds that even the nose cannot smell in a process called chemotaxis.

The first part, about smelling through the mouth, is an important part of why you should disregard all those articles, usually about wine, that say "you can only taste five tastes, so any complex favor profiles are mumbo jumbo." I mean, one should discount those based on experience alone, because, like, well, can you taste the difference between broccoli, cauliflower, kale, romaine lettuce, arugula, and sorrel? Yes. Of course. That's six.

(via Boing Boing)