The human brain is extremely good at problem-solving, at least relatively speaking. Cognitive scientists have been exploring how, exactly, people approach and solve problems – what cognitive strategies do we use, and how optimal are they. A recent study extends this research and includes a comparison of human problem-solving to machine learning. Would an AI, which can find an optimal strategy, follow the same path as human solvers?

The study was specifically designed to look at two specific cognitive strategies, hierarchical thinking and counterfactual thinking. In order to do this they needed a problem that was complex enough to force people to use these strategies, but not so complex that it could not be quantified by the researchers. They developed a system by which a ball may take one of four paths, at random, through a maze. The ball is hidden from view to the subject, but there are auditory clues as to the path the ball is taking. The clues are not definitive so the subject has to gather information to build a prediction of the ball’s path.

What the researchers found is that subjects generally started with a hierarchical approach – this means they broke the problem down into simpler parts, such as which way the ball went at each decision point. Hierarchical reasoning is a general cognitive strategy we employ in many contexts. We do this whenever we break a problem down into smaller manageable components. This term more specifically refers to reasoning that starts with the general and then progressively hones in on the more detailed. So far, no surprise – subjects broke the complex problem of calculating the ball’s path into bite-sized pieces.

What happens, however, when their predictions go awry? They thought the ball was taking one path but then a new clue suggests is has been taking another. That is where they switch to counterfactual reasoning. This type of reasoning involves considering the alternative, in this case, what other path might be compatible with the evidence the subject has gathered so far. We engage in counterfactual reasoning whenever we consider other possibilities, which forces us to reinterpret our evidence and make new hypotheses. This is what subjects did, h0wever they did not do it every time. In order to engage in counterfactual reasoning in this task the subjects had to accurately remember the previous clues. If they thought they did have a good memory for prior clues, they shifted to counterfactual reasoning. If they did not trust their memory, then they didn’t.

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Citrus greening (also called Huanglongbing or HLB) is an infectious disease affecting citrus trees in Florida. It is a bacterium, Candidatus Liberibacter asiaticus, and spread by an invasive fly, the Asian citrus psyllid. Since 2004 it has caused a reduction in the Florida citrus industry by 90% and doubled production costs. It is close to completely wiping out the Florida citrus industry. Various methods have been tried to keep it under control, but they have all failed.

There is good news, however. The University of Florida in collaboration with the company Soilcea, has developed a GMO orange that is highly resistant to citrus greening. They expect to have commercial trees available by the Spring of 2027. The limiting factor is that it takes years to grow test trees to see that they remain resistant and produce viable fruit. So far the test trees are doing well.

The company licensed the finding of Nian Wang, a professor at the University of Florida, who found that the bacterium is dependent upon interactions with the host that can be traced to several genes. The company used CRISPR to silence those genes, making it more difficult for the bacterium to infect plants and thereby making the plants resistant to infection. This approach has apparently worked, although again we won’t be sure until the first test trees reach maturity.

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First, don’t get too excited, this is a laboratory study, which means if all goes well we are about a decade or more from an actual treatment. The study, however, is a nice demonstration of the potential of recent biotechnology, specifically mRNA technology and lipid nanoparticles. We are seeing some real benefits building on decades of basic science research. It is a hopeful sign of the potential of biotechnology to improve our lives. It is also a painful reminder of how much damage is being done by the current administration’s defunding of that very science and the institutions that make it happen.

The study –Efficient mRNA delivery to resting T cells to reverse HIV latency – is looking for a solution to a particular problem in the treatment of HIV. The virus likes to hide inside white blood cells (CD4⁺ T cells). There the virus will wait in a latent stage and can activate later. It acts as a reservoir of virus that can keep the infection going, even in the face of effective anti-HIV drugs and immune attack. It is part of what makes HIV so difficult to fully eliminate from the body.

We already have drugs that address this issue. They are called, appropriately, latency-reversing agents (LRAs), and include Romidepsin, Panobinostat, and Vorinostat. These drugs inhibit an enzyme which allows the virus to hide inside white blood cells. So this isn’t a new idea, and there are already effective treatments, which do make other anti-HIV drugs more effective and keep viral counts very low. But they are not quite effective enough to allow for total virus elimination. More and more effective LRAs, therefore, could be highly beneficial to HIV treatment.

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In the movie Blade Runner 2049 (an excellent film I highly recommend), Ryan Gosling’s character, K, has an AI “wife”, Joi, played by Ana de Armas. K is clearly in love with Joi, who is nothing but software and holograms. In one poignant scene, K is viewing a giant ad for AI companions and sees another version of Joi saying a line that his Joi said to him. The look on his face says everything – an unavoidable recognition of something he does not want to confront, that he is just being manipulated by an AI algorithm and an attractive hologram into having feelings for software. K himself is also a replicant, an artificial but fully biological human. Both Blade Runner movies explore what it means to be human and sentient.

In the last few years AI (do I still need to routinely note that AI stands for “artificial intelligence”?) applications have seemed to cross a line where they convincingly pass the classic Turing test. AI chatbots are increasingly difficult to distinguish from actual humans. Overall, people are only slightly better than chance at distinguishing human from AI generated text. This is also a moving target, with AIs advancing fairly quickly. So the question is – are we at a point where AI chatbot-based apps are good enough that AIs can serve as therapists? This is a complicated question with a few layers.

The first layer is whether or not people will form a therapeutic relationship with the AI, in essence reacting to them as if they are a human therapist. The point of the Blade Runner reference was just to highlight what I think the clear answer is – yes. Psychologists have long demonstrated that people will form emotional attachments to inanimate objects. We also imbue agency onto anything that acts like an agent, even simple cartoons. We project human emotions and motivations onto animals, especially our pets. People can also form emotional connections to other actual people purely online, even exclusively through text. This is just a fact of neuroscience – our brains do not need a physical biological human in order to form personal attachments. Simply acting or even just looking like an agent is sufficient.

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I was away on vacation the last week, hence no posts, but am now back to my usual schedule. In fact, I hope to be a little more consistent starting this summer because (if you follow me on the SGU you already know this) I am retiring from my day job at Yale at the end of the month. This will allow me to work full time as a science communicator and skeptic. I have some new projects in the works, and will announce anything here for those who are interested.

On to today’s post – I recently received an e-mail from Janyce Boynton, a former facilitator who now works to expose the pseudoscience of facilitated communication (FC). I have been writing about this for many years. Like many pseudosciences, they rarely completely disappear, but tend to wax and wane with each new generation, often morphing into different forms while keeping the nonsense at their core. FC has had a resurgence recently due to a popular podcast, The Telepathy Tapes (which I wrote about over at SBM). Janyce had this to say:

I’ll be continuing to post critiques about the Telepathy Tapes–especially since some of their followers are now claiming that my student was telepathic. Their “logic” (and I use that term loosely) is that during the picture message passing test, she read my mind, knew what picture I saw, and typed that instead of typing out the word to the picture she saw.

I shouldn’t be surprised by their rationalizations. The mental gymnastics these people go through!

They’re also claiming that people don’t have to look at the letter board because of synesthesia. According to them, the letters light up and the clients can see the “aura” of each color. Ridiculous. I haven’t been able to find any research that backs up this claim. Nor have I found an expert in synesthesia who is willing to answer my questions about this condition, but I’m assuming that, if synesthesia is a real condition, it doesn’t work the way the Telepathy Tapes folks are claiming it does.

For quick background, FC was created in the 1980s as a method for communicating to people, mostly children, who have severe cognitive impairment and are either non-verbal or minimally verbal. The hypothesis FC is based on is that at least some of these children may have more cognitive ability than is apparent but rather have impaired communication as an isolated deficit. This general idea is legitimate, and in neurology we caution all the time about not assuming the inability to demonstrate an ability is due purely to a cognitive deficit, rather than a physical deficit. To take a simple example, don’t assume someone is not responding to your voice because they have impaired consciousness when they could be deaf. We use various methods to try to control for this as much as possible.

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