#AtoZChallenge 2020: P Is for Poem and the Prefrontal Cortex

I was reading the dictionary. I thought it was a poem about everything. ~ Steven Wright

My random brain, which seems to be in the ascendency where the A to Z is concerned, thought first of the dictionary again today. The first word that jumped out was

• pachmann, who turned out to be a Russian pianist, not a computer game

followed by, among others,

• pachyblepharon – a thickening of the tarsal border of the eyelid

which sounds like something I might have ended up with when I disinfected my eye

and

• pachycephalosaurus – A large herbivorous dinosaur of the genus Pachycephalosaurus of the late Cretaceous Period. It grew to about 7.6 m (25 ft) long and had a domed skull up to 25.4 cm (10 inches) thick that was lined with small bumps and spikes. The thick skull may have been used for head-butting during mating displays
• pachychromatic – having coarse chromatin threads [not thick musical scales]
• pachydactyly – abnormal enlargement of fingers and toes

I figured out pachycephalosaurus and pachydactyly before looking them up, I’m pleased to say, since it means I haven’t forgotten all my Greek roots.

I then thought about random thought, and so googled “random brain,” and found an article (Cosmos, May 18 2017) describing a study in which

Neuroscientists at the Champalimaud Centre for the Unknown (CCU) in Lisbon, Portugal, reveal the unexpected finding in a report that aims to unpack how humans and other animals decide how and when to act.

In short, the scientists found that “‘[t]he brain’s prefrontal cortex – the seat of decision-making – has no input into the timing of random actions,'” but that

“‘[t]he medial prefrontal cortex appears to keep track of the ideal waiting time based on experience. The secondary motor cortex also keeps track of the ideal timing but in addition shows variability that renders individual decisions unpredictable.'”

The researchers were surprised at discovering the “‘not-well-appreciated “separation of powers” within the brain.'”

Personal observation underscores the finding: It’s four p.m., and William and Ernest are lying in the kitchen, watching David prepare their dinner and insulin injections. Several times a day they watch David go to the kitchen but at four o’clock they follow him. Their actions must be based on experience; hence the medial prefrontal cortex determines their action, and David’s as well. Human experience shows that if dinnertime is random, cats chew the carpet, a consummation devoutly not to be wished.

In the course of my mental ramblings, I thought of other things: Miss Petunia, an old neighbor well worth two or three posts, and more appropriate to the day, but better left to my putative novel.

Then there was my misuse of since in the paragraph following pachydactyly, because since means because, which I just used properly.

I also thought of stories about Mr. F., Mr. J., and Miss Fl., also not the best post material. To get them out of my system, I just put them in an email to a friend who has long suffered random thoughts I can’t make post-public.

I thought about changing the appearance of my blog, because I’m tired of looking at it, but how would I display my photographs so prominently?

I thought about checking the MoviesTV schedule, where I found a summary of Mighty Joe Young: “As their Hollywood dreams fade, a woman and her pet gorilla’s friendship is threatened.”

I thought, too, about several other things, some beginning with P, that I’ve since (properly used) forgotten.

So works the random brain. I used to know how forgetting works, but no matter.

One bit from the study I’ve just remembered: “‘The combination of reason and randomness that drives how and when action-based decisions are made is thought to carry an evolutionary fitness dividend.'”

I’ve found it can also carries an evolutionary deficit, but that’s a topic for another post.