20 December 2023

Honest Placebos

I've come across a few things referencing placebos lately, in particular 'transparent' or 'open' placebos where the fact that it contains no known effective ingredient is not hidden.

One is a link to this research on "Effects of open-label placebos in clinical trials: a systematic review and meta-analysis" from Nature dated Feb 16, 2021:

Open-label placebos (OLPs) are placebos without deception in the sense that patients know that they are receiving a placebo. The objective of our study is to systematically review and analyze the effect of OLPs in comparison to no treatment in clinical trials.

We found a significant overall effect (standardized mean difference = 0.72, 95% Cl 0.39–1.05, p < 0.0001, I2 = 76%) of OLP. Thus, OLPs appear to be a promising treatment in different conditions but the respective research is in its infancy.

Then in perusing Andy Clark's latest book The Experience Machine, which posits the brain as a prediction engine, constantly engaging with sensory input both consciously and unconsciously to enable action, he concludes with some material about what he refers to as 'honest' placebos:

Honest placebos appear to work by activating subterranean expectations through superficial indicators of reliability and efficacy such as good packaging and professional presentation (foil and blister packs, familiar fond, size and uniformity of the pills, and so on). This is because - as we have seen - the bulk of the brain's prediction empire is nonconscious.

Clark reviews a number of other findings in his 'Hacking the Prediction Machine' chapter, and in a sense concludes:

In the end, it looks like anything that can be done to increase our confidence in an intervention, procedure, or outcome is likely to have real benefits. 

He also describes use of certain psychedelic drugs as having the potential to 'reset' the prediction machine in very useful ways.

18 December 2023

Conversing with a whale

This Dec. 12, 2023 report from the Seti Institute, Whale-SETI: Groundbreaking Encounter with Humpback Whales Reveals Potential for Non-Human Intelligence Communication seems encouraging.

In response to a recorded humpback ‘contact’ call played into the sea via an underwater speaker, a humpback whale named Twain approached and circled the team’s boat, while responding in a conversational style to the whale ‘greeting signal.’ During the 20-minute exchange, Twain responded to each playback call and matched the interval variations between each signal.

I've long thought it would make sense to attempt communication with the intelligent species on our own planet! 

19 November 2023

Evolution and Free Will

Pulled from the blog list, the recent Brain Science podcast with Kevin Mitchell is worthwhile.

As with his new book, it's titled "Free Agents: How Evolution Gave Us Free Will" and was posted Oct 27, 2023.

02 May 2023

AI reads the brain?

Well, long time no posting!

The post "A.I. trained to read minds and translate private thought to text via brain scans" from BoingBoing caught my eye. Here with extensive training on a specific person's brain activity while listening to spoken text, is able to correlate later brain activity (while watching silent films or thinking of speaking) and do pretty well at reconstructing at least some of what the person "had in mind". Note though that patterns for one person do not carry over to other people.

This language-decoding method had limitations, Dr. Huth and his colleagues noted. For one, fMRI scanners are bulky and expensive. Moreover, training the model is a long, tedious process, and to be effective it must be done on individuals. When the researchers tried to use a decoder trained on one person to read the brain activity of another, it failed, suggesting that every brain has unique ways of representing meaning.

14 January 2018

Worms re-grow brains with old memories?

How much do we really know about memory storage?  This story from National Geographic may make you think again: "Decapitated Worms Re-Grow Heads, Keep Old Memories" by Carrie Arnold (dated July 16, 2013).
After the team verified that the worms had memorized where to find food, they chopped off the worms’ heads and let them regrow, which took two weeks. 
Then the team showed the worms with the regrown heads where to find food, essentially a refresher course of their light training before decapitation. 
Subsequent experiments showed that the worms remembered where the light spot was, that it was safe, and that food could be found there. The worms’ memories were just as accurate as those worms who had never lost their heads.

16 May 2016

What do we really know about Matter?

Two recent articles hit a similar theme, pushing the notion that our experience (consciousness) is in some sense on firmer ground that our understanding of physical matter.

The first I came across today via Twitter: "Consciousness isn't a Mystery: It's Matter" by philosopher Galen Strawson in the New York Times (May 16, 2016).  Here's the gist:
... we know exactly what consciousness is — where by “consciousness” I mean what most people mean in this debate: experience of any kind whatever. It’s the most familiar thing there is, whether it’s experience of emotion, pain, understanding what someone is saying, seeing, hearing, touching, tasting or feeling. It is in fact the only thing in the universe whose ultimate intrinsic nature we can claim to know. It is utterly unmysterious.

The nature of physical stuff, by contrast, is deeply mysterious, and physics grows stranger by the hour. (Richard Feynman’s remark about quantum theory — “I think I can safely say that nobody understands quantum mechanics” — seems as true as ever.) Or rather, more carefully: The nature of physical stuff is mysterious except insofar as consciousness is itself a form of physical stuff
I think this is on the right track...  emphasizing the primacy of experience, but not claiming that experience is necessarily exposing the actual nature of 'physical stuff'.  It's easy to assume we have a good handle on Matter, when in fact we've only discovered some rules about it, along with the working assumption that whatever it is, if you get a complex enough organization you get what we think of as conscious experience.

Back in April, Amanda Gefter wrote on and interviewed cognitive scientist (and author of Visual Intelligence) Donald Hoffman in an article entitled "The Case Against Reality" in The Atlantic.  Hoffman argues that our evolutionary path driven by fitness means that we have no reliable means of accessing what's really out there.
The idea that what we’re doing is measuring publicly accessible objects, the idea that objectivity results from the fact that you and I can measure the same object in the exact same situation and get the same results — it’s very clear from quantum mechanics that that idea has to go. Physics tells us that there are no public physical objects. So what’s going on? Here’s how I think about it. I can talk to you about my headache and believe that I am communicating effectively with you, because you’ve had your own headaches. The same thing is true as apples and the moon and the sun and the universe. Just like you have your own headache, you have your own moon. But I assume it’s relevantly similar to mine. That’s an assumption that could be false, but that’s the source of my communication, and that’s the best we can do in terms of public physical objects and objective science.
Presumably since all humans are on the same evolutionary path, we do indeed have similar assumptions and experiences. But it may be much harder to communicate with beings coming from different evolutionary pressures.

21 October 2015

More news on the worm C. elegans - a few more neurons?

 Been awhile since I've been active here, but this exciting worm news certainly rates a post.  To get caught up, check this previous post: Modeling the Worm!

In this story from Nature, "Surprise 'mystery' neurons found in male worms" the title gives it away.
The neurons help the worms learn when to prioritize mating over eating, revealing how a seemingly simple brain can be capable of a complex learned behaviour — and one that differs between the sexes.

Caenorhabditis
 elegans worms are the model animal of choice for many neuroscientists, because their neural circuits are so simple that they can be mapped in full. They have two sexes: hermaphrodite and male. Hermaphrodites, the best studied, have just 302 neurons, but males have more — the MCMs raise their total to 385 neurons.
So it looks like there's more work to be done to get a good handle on the worm brain.

22 December 2014

Modeling the worm!

Recent physical simulation of the c. elegans 302-neuron worm with Lego, as reported here at the I Programmer site on Nov. 16, 2014, "A Worm's Mind In A Lego Body" by Lucy Black.  This is a nice follow-up to my May 2013 post Modeling Simple Worms.  The claim here is that the computer model of these neurons is able to produce simple physical behavior that is like the worm behavior (note that the worm is very small and only capable of simple behavior).  There's a video that shows the lego model in action.
It is claimed that the robot behaved in ways that are similar to observed C. elegans. Stimulation of the nose stopped forward motion. Touching the anterior and posterior touch sensors made the robot move forward and back accordingly. Stimulating the food sensor made the robot move forward.

The key point is that there was no programming or learning involved to create the behaviors. The connectome of the worm was mapped and implemented as a software system and the behaviors emerge.

The connectome may only consist of 302 neurons but it is self-stimulating and it is difficult to understand how it works - but it does.
As for the claim about the worm's mind...  well we don't know much about a worm's mind, so how could we know if this model captures it?

The simulation project is run by Tim Busbice at The Connectome Engine.  Another story on the simulation at the New Scientist site "First digital animal will be perfect copy of real worm."