Humans identify and call each other by specific names. So far this advanced cognitive behavior has only been identified in a few other species, dolphins, elephants, and some parrots. Interestingly, it has never been documented in our closest relatives, non-human primates – that is, until now. A recent study finds that marmoset monkeys have unique calls, “phee-calls”, that they use to identify specific individual members of their group. The study also found that within a group of marmosets, all members use the same name to refer to the same individual, so they are learning the names from each other. Also interesting, different families of marmosets use different kinds of sounds in their names, as if each family has their own dialect.

In these behaviors we can see the roots of language and culture. It is not surprising that we see these roots in our close relatives. It is perhaps more surprising that we don’t see it more in the very closest relatives, like chimps and gorillas. What this implies is that these sorts of high-level behaviors, learning names for specific individuals in your group, is not merely a consequence of neurological develop. You need something else. There needs to be an evolutionary pressure.

That pressure is likely living in an environment and situation where families members are likely to be out of visual contact of each other. Part of this is the ability to communicate at long enough distance that will put individuals out of visual contact. For example, elephants can communicate over miles. Dolphins often swim in murky water with low visibility. Parrots and marmosets live in dense jungle. Of course, you need to have that evolutionary pressure and the neurological sophistication for the behavior – the potential and the need have to align.

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I am not the first to say this but it bears repeating – it is wrong to use the accusation of a mental illness as a political strategy. It is unfair, stigmatizing, and dismissive. Thomas Szasz (let me say straight up – I am not a Szaszian) was a psychiatrist who made it his professional mission to make this point. He was concerned especially about oppressive governments diagnosing political dissidents with mental illness and using that as a justification to essentially imprison them.

Szasz had a point (especially back in the 1960s when he started making it) but unfortunately took his point way too far, as often happens. He decided that mental illness, in fact, does not exist, and is 100% political oppression. He took a legitimate criticism of the institution of mental health and abuse by oppressive political figures and systems and turned it into science denial. But that does not negate the legitimate points at the core of his argument – we should be careful not to conflate unpopular political opinions with mental illness, and certainly not use it as a deliberate political strategy.

While the world of mental illness is much better today (at least in developed nations), the strategy of labeling your political opponents as mentally ill continues. I truly sincerely wish it would stop. For example, in a recent interview on ABC, senator Tom Cotton was asked about some fresh outrageous thing Trump said, criticism of which Cotton waved away as “Trump Derangement Syndrome”.

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Gotta love the title of this paper: “A critical hit: Dungeons and Dragons as a buff for autistic people“. Dungeons & Dragons (D&D) is a tabletop roleplaying game where a small group of people each play characters adventuring in an imaginary world run by the dungeon master (DM). (That explanation was probably not necessary for the majority of readers here, but just to be thorough.) The game has just celebrated its 50th anniversary, which was even commemorated by official US stamps.

The game certainly has a very different reputation today than it did in the 70s and 80s. Back then it was seen as the exclusive domain of extreme geeks and nerds, mostly males who needed a distraction from the fact that they had no chance of finding a girlfriend. This was never true, but that was the reputation. In the 80s things got even worse, with D&D being tied to the “satanic panic” of that decade. The game was blamed, mostly by fundamentalist religious groups, for demon worship, witchcraft, and resulting in suicides and murder. I still remember when the school board in our town had a debate about whether or not the game should be banned from school grounds. The adults having the conversation had literally no idea what they were talking about, and filled the gaps in their knowledge with their own vivid imaginations.

In reality D&D and similar roleplaying games are perfectly wholesome and have a lot of positive attributes. First, they are extremely social. They are especially good for people who may find social interactions challenging or at least very demanding. While roleplaying you are in a social safe-space, where you can let aspects of your personality out to play. The game is also mostly pure imagination. Other than a few aids, like dice for random outcome generation, maps and figures, the adventure takes place in the minds of the players, helped along by the GM. The game can therefore help people develop social connections and social skills, and to learn more about themselves and close friends.

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Often times the answer to a binary question is “yes”. Is artificial intelligence (AI) a powerful and quickly advancing tool or is it overhyped? Yes. Are opiates useful medicines or dangerous drugs? Yes. Is Elon Musk a technological visionary or an eccentric opportunist? This is because the world is usually more complex and nuanced than our false dichotomy or false choice simplistic thinking. People and things can contain disparate and seemingly contradictory traits – they can be two things at the same time.

This was therefore my immediate reaction to the question – are AI companions a potentially healthy and useful phenomenon, or are they weird and harmful? First let me address a core neuropsychological question underlying this issue – how effective are chatbot companions, for just companionship, or for counseling, or even as romantic partners? The bottom line is that the research consistently shows that they are very effective.

This is likely a consequence of how human brains are typically wired to function. Neurologically speaking, we do not distinguish between something that acts alive and something that is alive. Our brains have a category for things out there in the world that psychologists term “agents”, things that are acting on their own volition. There is a separate category for everything else, inanimate objects. There are literally different pathways in the brain for dealing with these two categories, agents and non-agents. Our brains also tend to overall the agent category, and really only require that things move in a way that suggest agency (moving in a non-inertial frame, for example). Perhaps this makes evolutionary sense. We need to know, adaptively, what things out there might be acting on their own agenda. Does that thing over there want to eat me, or is it just a branch blowing in the wind.

Humans are also intensely social animals, and a large part of our brains are dedicated to social functions. Again, we tend to overcall what is a social agent in our world. We easily attribute emotion to cartoons, or inanimate objects that seem to be expressing emotions. Now that we have technology that can essentially fake human agency and emotion, this can hack into our evolved algorithms which never had to make a distinction between real and fake agents.

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If either of the two presumptive nominees for the major political parties in the US are elected in November they will be the oldest person ever to be inaugerated as president. What implications does this have? As a neurologist who sees patients every workday of various ages, evaluates them, and explicitly investigates the effects of aging on their function, I have some thoughts.

The first thing to realize is that aging affects different people differently. Especially once people get north of 40 you start to see significant and growing divergence in how well people age, in terms of their health and various aspects of functioning. I have seen many patients in their 90s who are completely sharp and fully functional or have just specific issues to deal with, but are overall healthy. I have also seen patients in their 50s who are wrecked and suffering from various aspects of declining health.

This divergence is partly due to the luck of genetics, and partly due to lifestyle. Some people have a chronic illness that dramatically affects their aging. Others may have suffered an injury with long term effects that get more challenging with age. While others have engaged in one or more poor lifestyle choices and have paid a heavy toll. Chronic alcohol use disorder, for example, can be devastating, adding years or decades to one’s apparent age. Smoking also takes its toll.

For these reasons, what we can say about a person based upon just a number is actually quite limited. We can make statistical comments, but that’s all. Even there, we can only describe what is typical, but there are exceptions. There are, for example, so-called “super agers” who do not develop the typical brain changes that most people do with age.

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This is a great scientific question because it challenges how we ask and answer scientific questions. Are animals conscious? This is a question discussed in a recent BBC article that piqued my interest. They eventually get to a question that they should have opened with – how do we specifically define “consciousness”? We can’t answer questions about an alleged phenomenon unless we know what it is. Ideally we would have an operational definition, a list of inclusion and exclusion criteria that need to be met to fit the definition.

So I am going to start with this question – how do we define consciousness? I think there are at least two different contexts here. In medicine we use the term to refer to different states in people. We know, from our own experience, that humans are conscious, and from one point of view we define consciousness as what humans experience. We assume other fully functioning humans are conscious because we are, and there is no reason to think that other beings with brains similar to our own have a fundamentally different phenomenon driving their behavior. In fact part of consciousness is a theory of mind, which is the ability to think about what other beings think and feel.

So when we talk about consciousness in humans the question revolves around the health and functioning of the brain. Someone might be unconscious, or comatose, or vegetative. We label these as “disorders of consciousness”. We might also discuss consciousness in the context of healthy altered states, such as sleeping. Here we do have very specific technical definitions, based upon neurological examination. However, even here our definition is being challenged by new technology, such as functional MRI scanning, which may shows signs of subtle consciousness in someone who does not show signs on exam.

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We are rapidly entering the era of neuromodulation – using electrical and magnetic fields in order to increase or decrease the activity of specific regions and circuits in the brain. Such treatments are already shown to be effective in treating some Parkinson’s symptoms, depression, OCD, migraines, and other neurological and psychiatric conditions. Computational models of brain anatomy and the connectome have dramatically increased the utility of neuromodulation. We are still on the steep part of the curve, and it will be interesting to see how far this modality goes in the next 10-20 years.

But there is one technical challenge – reaching the deep brain structures where many of the potentially targeted conditions can be found. The problem is that any electrical or magnetic field has to go through the more superficial brain tissue to get to the deeper structures. The current solution to this problem is to use invasive techniques, such as placing wires in the brain. So called “deep brain stimulation” is now done routinely, using guided stereotactic techniques, but a non-invasive way to accomplish the same goal could lead to a dramatic increase in the utility of neuromodulation.

Researchers have now published a proof of concept study looking at what they call transcranial temporal interference stimulation (tTIS).  The idea of tTIS is actually rather simple – it exploits the phenomenon of interference. Waves, regardless of what kind of waves they are, display certain core behaviors, one of which is interference. Wave are basically additive. If a peak hits a peak you get a bigger peak. If the peak of one wave coincides with the trough of another wave, the two waves will cancel each other out. This is how noise cancelling headphones work, for example.

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One of the most difficult situations that a person can face is to have a loved-one in a critical medical condition and have to make life-or-death medical decisions for them. I have been in this situation many times as the consulting neurologist, and I have seen how weighty this burden can be on family members. Advanced directives are helpful, but they cannot predict every possible situation or anticipate every medical nuance, so still, decisions have to be made.

One thing is also clear – the better we are able to predict outcomes, the easier decision-making becomes. Uncertainty is the most difficult aspect of choosing, for example, whether or not to withdraw life-saving interventions. For this reason there has been a lot of research trying to help do exactly that – predict outcomes in various situations of neurological injury, so at least family members can make the most informed decision possible.

But one thing that doctors do not have, as we are fond of saying, is a crystal ball. We cannot say what an individual’s outcome will be, only make statistical statements based on predictive variables. Still, statistics can be extremely helpful.

A recent study adds to the literature addressing this question. They look at the outcomes of 146 adults with severe traumatic brain injury admitted to an ICU. They looked at whether or not there was withdrawal of life-sustaining treatment (WLST) and compared the characteristics of both groups. Not surprisingly, those who were WLST + were older on average and had more severe injury. The researchers also looked at those who were WLST – (did not have withdrawal of life-sustaining treatment) and tracked their outcomes.

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I have not written before about Havana Syndrome, mostly because I have not been able to come to any strong conclusions about it. In 2016 there was a cluster of strange neurological symptoms among people working at the US Embassy in Havana, Cuba. They would suddenly experience headaches, ringing in the ears, vertigo, blurry vision, nausea, and cognitive symptoms. Some reported loud whistles, buzzing or grinding noise, usually at night while they were in bed. Perhaps most significantly, some people who reported these symptoms claim that there was a specific location sensitivity – the symptoms would stop if they left the room they were in and resume if they returned to that room.

These reports lead to what is popularly called “Havana Syndrome”, and the US government calls “anomalous health incidents” (AHIs). Eventually diplomats in other countries also reported similar AHIs. Havana Syndrome, however, remains a mystery. In trying to understand the phenomenon I see two reasonable narratives or hypotheses that can be invoked to make sense of all the data we have. I don’t think we have enough information to definitely reject either narrative, and each has its advocates.

One narrative is that Havana Syndrome is caused by a weapon, thought to be a directed pulsed electromagnetic or acoustic device, used by our adversaries to disrupt American and Canadian diplomats and military personnel.  The other is that Havana Syndrome is nothing more than preexisting conditions or subjective symptoms caused by stress or perhaps environmental factors. All it would take is a cluster of diplomats with new onset migraines, for example, to create the belief in Havana Syndrome, which then takes on a life of its own.

Both hypotheses are at least plausible. Neither can be rejected based on basic science as impossible, and I would be cautious about rejecting either based on our preexisting biases or which narrative feels more satisfying. For a skeptic, the notion that this is all some kind of mass delusion is a very compelling explanation, and it may be true. If this turns out to be the case it would definitely be satisfying, and we can add Havana Syndrome to the list of historical mass delusions and those of us who lecture on skeptical topics can all add a slide to our Powerpoint presentations detailing this incident.

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When I use my virtual reality gear I do practical zero virtual walking – meaning that I don’t have my avatar walk while I am not walking. I general play standing up which means I can move around the space in my office mapped by my VR software – so I am physically walking to move in the game. If I need to move beyond the limits of my physical space, I teleport – point to where I want to go and instantly move there. The reason for this is that virtual walking creates severe motion sickness for me, especially if there is even the slightest up and down movement.

But researchers are working on ways to make virtual walking a more compelling, realistic, and less nausea-inducing experience. A team from the Toyohashi University of Technology and the University of Tokyo studied virtual walking and introduced two new variables – they added a shadow to the avatar, and they added vibration sensation to the feet. An avatar is a virtual representation of the user in the virtual space. Most applications allow some level of user control over how the avatar is viewed, but typically either first person (you are looking through the avatar’s eyes) or third person (typically your perspective is floating above and behind the avatar). In this study they used only first person perspective, which makes sense since they were trying to see how realistic an experience they can create.

The shadow was always placed in front of the avatar and moved with the avatar. This may seem like a little thing, but it provides visual feedback connecting the desired movements of the user with the movements of the avatar. As weird as this sounds, this is often all that it takes to not only feel as if the user controls the avatar but is embodied within the avatar. (More on this below.) Also they added four pads to the bottom of the feet, two on each foot, on the toe-pad and the heel. These vibrated in coordination with the virtual avatar’s foot strikes. How did these two types of sensory feedback affect user perception?

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