Send in the clowns?

According to the sensationalist press, no, don't send them in, this coming evening on October 31. In memorial to the clowns, then, a video:

Weekend BioRxiv Preprint Review: The Neural Correlates of Dreaming

Not long after the development of the electoencephalogram (EEG) it was found that the EEG during sleep shows more synchronized and slower activity most of the time compared to our waking EEG. This was termed "slow wave sleep." These predominating slow wave sleep periods are interrupted by briefer periods of desynchronized, faster EEG activity, during which there are rapid movements of the eyes: this is termed REM sleep.

Most, but not all, dreams occur during REM sleep. This makes sense if faster and desynchronous brain activity is present when the brain is actively processing experiences, since dreams seem to be a kind of experience the brain can process. The rapid eye movements are similar to those we use when looking around us when awake, and it is likely that visual imagery during REM sleep is accompanied by the dreamer moving the eyes in a similar way they would if the dream images were actually in their waking vision. Other muscles of the body are quite relaxed during dreams: if they are not, a sleep disturbance ("REM behavior disorder") in which dream actions are accompanied by body movement may occur.

What of the dreams during slow wave (non-REM, or NREM) sleep? The study below suggests that even though much of the brain during such dreams shows slow activity, there is still a small area of the posterior brain which shows faster, desynchronized activity during dreams that occur during non-REM sleep. The area of the brain which has such faster activity during NREM dreaming is the same area activated by visual imagery during wakefulness, suggesting that, philosophically speaking, visual qualia are being generated during such dreams.

Studies such as this are difficult, time consuming, and expensive to do well, since one must, for each data point, have subjects sleep in the lab with an investigator or well trained tech able to wake the subjects at the right moment to ask if the subject was indeed dreaming when awakened. The investigators are to be complimented for their work.

One quibble: the investigators say at the end of their paper that "our findings indicate that the neural correlate of consciousness, rather than involving the broad lateral fronto-parietal network, is restricted to a posterior hot zone." This would be true if having visual imagery means we must be conscious. But are we really conscious while dreaming? Certainly we are not conscious in the same way we are when awake.

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ABSTRACT

The neural correlates of dreaming

Francesca Siclari, Benjamin Baird, Lampros Perogamvros, Giulio Bernardi, Joshua J LaRocque, Brady Riedner, Melanie Boly, Bradley R Postle, Giulio Tononi

doi: http://dx.doi.org/10.1101/012443

Consciousness never fades during wake. However, if awakened from sleep, sometimes we report dreams and sometimes no experiences. Traditionally, dreaming has been identified with REM sleep, characterized by a wake-like, globally ‘activated’, high-frequency EEG. However, dreaming also occurs in NREM sleep, characterized by prominent low-frequency activity. This challenges our understanding of the neural correlates of conscious experiences in sleep. Using high-density EEG, we contrasted the presence and absence of dreaming within NREM and REM sleep. In both NREM and REM sleep, the presence of dreaming was associated with a local decrease in low-frequency activity in posterior cortical regions. High-frequency activity within these regions correlated with specific dream contents. Monitoring this posterior ‘hot zone’ predicted the presence/absence of dreaming during NREM sleep in real time, suggesting that it may constitute a core correlate of conscious experiences in sleep

Sponsorship Rewarded: a Long-Awaited Kickstarter Arrives

Over 4 years ago, in 2012, I pledged $35 toward a book to be written by a botanist from Europe who had moved to Costa Rica. The book was to be called Tropical Fruits of the World. The author, Rolf Blancke, used his Kickstarter funds, a relatively small $8,128 (goal: $7500) to travel and photograph rare tropical fruits.

Years passed, and we heard that the book was coming, but then the publisher changed, and eventually I wondered if the work would ever reach (pun intended) fruition.

So I was surprised and happy when a copy of the book, with its pink dragonfruit cover illustration, arrived today in the mail! This is a big work. Including three other chapters (on tropical palms, tubers, and spices and herbs) along with the promised chapter on fruit, it is a delight so far. The book is also on Amazon at this link, and I plan to review it here, eventually. I'll just say that among the 235 fruits photographed, described and cataloged in the book, there are many I've never seen, even at the Hilo Farmers' Market, which I had thought had them all.

Under some models of climate change, a large portion of the southern continental United States will be quite capable of growing many of these fruits by the time our great-grandchildren are of the age to plant them. So it's good to have information like this out there.

Kickstarter came through eventually this time.

Hawaii Volcano Sulfur Dioxide Emissions vs US Total Emissions.

With the decline in coal burning, sulfur dioxide pollution emissions in the US mainland have dipped down to about 3 million tons a year in recent years. On the other hand, based on the measurements taken with the geological model adopted over the past year, sulfur dioxide emissions from Kilauea's vents within the Hawai'i Volcanoes National Park may be over 2 million tons a year. So the National Park Service, in Hawaii, remains our country's biggest emission source of sulfur dioxide, a cause of acid rain.

Anthropomorphic climate change is but part of a much bigger system of the earth's crust and atmosphere that remains dynamic with or without human outputs.

Homebrew (using insulin reusable autoinjector) EpiPen Alternative

If patients want this EpiPen alternative, but feel unable to meet the requirement for relatively sterile technique during assembly, they can have their doctor assemble it for them. If so, it should probably be replaced every few months.

Here.

Pete Basabe’s Butterflyfish (Prognathodes basabei Pyle and Kosaki 2016)

A new butterflyfish, found in the northwest Hawaiian islands of the newly expanded Papahānaumokuākea Marine National Monument, is pictured here, taken by yours truly not in the water, but with a cell phone. Two of these new and exceedingly rare fish are now in the tank at the Mokupāpapa Discovery Center here.

A song to commemorate this new medium-deep reef species seems appropriate, so below there is an indirect Youtube link to Iz's rendition of a nearly century-old Kona, Hawaii fish song by Lot Kauwe, honoring the reef fish of the island. Pete Basabe is a Kona diver who has contributed greatly to reef fish knowledge here.

Bayesian Version of the Principle of Sufficient Reason

There are no prior probabilities of measure zero for any actual events.