Archive for the 'Neuroscience' Category

Aug 23 2022

Do We Need a New Theory of Decision Making?

Published by under Neuroscience

How people make decisions has been an intense area of study from multiple angles, including various disciplines within psychology and economics. Here is a fascinating article that provides some insight into the state of the science addressing this broad question. It is framed as a meta-question – do we have the right underlying model that properly ties together all the various aspects of human decision-making? It is not a systematic review of this question, and really just addresses one key concept, but I think it helps frame the question.

The title reflects the author’s (Jason Collins) approach – “We don’t have a hundred biases, we have the wrong model.” The article is worth a careful read or two if you are interested in this topic, but here’s my attempt at a summary with some added thoughts. As with many scientific phenomena, we can divide the approach to human decision making into at least two levels, describing what people do and an underlying theory (or model) as to why they behave that way. Collins is coming at this mostly from a behavioral economics point of view, which starts with the “rational actor” model, the notion that people generally make rational decisions in their own self-interest. This model also includes the premise the individual have the computational mental power to arrive at the optimal decision, and the willpower to carry it out. When research shows that people deviate from a pure rational actor model of behavior, those deviations are deemed “biases”. I’ve discussed many such biases in this blog, and hundreds have been identified – risk aversion, sunk cost, omission bias, left-most digit bias, and others. It’s also recognized that people do not have unlimited computational power or willpower.

Collins likens this situation to the Earth-centric model of the universe. Geocentrism was an underlying model of how the universe worked, but did not match observations of the actual universe. So astronomers introduced more and more tweaks and complexities to explain these deviations. Perhaps, Collins argues, we are still in the “geocentrism” era of behavioral psychology and we need a new underlying model that is more elegant, accurate, and has more predictive power – a heliocentrism for human decision-making. He acknowledges that human behavior it too complex and multifaceted to follow a model as simple and elegant as, say, Kepler’s laws of planetary motion, but perhaps we can do better than the rational actor model tweaked with many biases to explain each deviation.

Continue Reading »

No responses yet

Aug 08 2022

The Psychology of FOMO

Published by under Neuroscience

One of the many unintended consequences of social media is what is popularly referred to as FOMO – fear of missing out. People see all the wonderful things people are doing and buying in their social media profiles, and fear that they are missing out on the good life, or the latest trend, or perhaps some investment opportunity. This is the social media equivalent of “keeping up with the Joneses”. FOMO results from a basic human psychological tendency, to determine our own happiness by comparing ourselves to some relative standard, whether that’s our neighbors, our social group, or what we see on TV or on people’s Facebook pages.

This phenomenon also interacts with another, that we determine our happiness relative to our own current state, meaning that we habituate to our current situation. Functionally what this means is that if we want to remain happy we constantly need more – more than we have now, and more that other people have. The habituation phenomenon was humorously depicted in the video game, Portal 2 (an excellent game, highly recommended if you like video games). The main antagonist is an AI that is programmed to run the player through various testing scenarios. Each time the player completes a test the AI gets the silicon version of a dose of dopamine, but the digital Nirvana is short-lived and it has to run another test to maintain the good feeling. But it rapidly habituates to this feedback, with shorter and less intense reward meaning it has to test faster and harder.

This is essentially how humans function as well. We are never content. We cannot remain happy by standing still. We need whatever other people have, and we need more than we currently have. This lines up with research into happiness. Making more money does make people happier, up to the level where basic needs and security are met (in the US this is now about 75k per year). Some researchers frame this not as money making people happy, but rather not having enough money to meet basic needs is stressful and makes people unhappy. Beyond this basic level, increasing income does not correlate with happiness. Whether you make 75 thousand a year or 75 million a year does not matter. Further, everyone thinks that they would be happy if they just made 20% more than they currently make – regardless of how much that is. We habituate to our current situation and then think we need a little more to be happy.

Continue Reading »

No responses yet

Aug 02 2022

Political Ideology and the Brain

Published by under Neuroscience

Political neuroscientists are trying to answer a basic question – what is the relationship between political ideology and brain function? Actually this is a horrifically complex question, but we are making some incremental progress, and a recent study adds a new layer of information. But let me first back up and give some thoughts on the entire enterprise.

Obviously political ideology is a brain phenomenon, in the way that all cognitive function is a brain phenomenon. But there are interesting deeper questions. How much of political ideology is learned or absorbed from the environment, and how much is a function of our genetic neurological predisposition (nature vs nurture)? The number one predictor of political ideology is the ideology of one’s parents. But this, of course, cuts both ways – we inherit genes from our parents, but they also dominantly affect the environment of our childhood. Twin studies (looking at the political ideology of twins separated at birth) suggest that political ideology is at least partly genetic. So unsurprisingly the answer is that genetic and environmental factors are likely working together to influence political ideology.

Another layer to consider is how we define political ideology? For studies based in the US, a typical liberal vs conservative scale is used. But we have to ask – is American liberal vs conservative politics fundamental to human psychology, or is it a particular cultural manifestation that may only indirectly relate to basic cognitive function? Perhaps, in other words, we’re looking in the wrong place, where the lighting is good but not necessarily where the phenomenon is really located. All research that looks for neuroanatomic correlates suffers from this fundamental question. If we look for the neuroanatomical correlates of depression, for example, we have to ask what depression is, and if it is a foundational phenomenon or an epiphenomenon. Is it a fundamental property of neurological functioning, or just a manifestation of a deeper neurological functioning?

Continue Reading »

No responses yet

Jul 25 2022

The Alzheimer’s Research Fraud Case

Published by under Neuroscience

We are still relatively early in the investigation of possible fraud or misconduct relating specifically to amyloid beta (Aβ) in Alzheimer’s disease, so consider this all preliminary. However, independent analysis does allegedly find some highly suspect data in a series of images used in publications by one particular researcher, Sylvain Lesné of the University of Minnesota.  Science magazine has done a good review of what we know at this time. I will quickly review the status of this investigation and what the whole episode means for scientific research in general, and Alzheimer’s research in particular.

For background, Alzheimer’s disease (AD) is a complex neurodegenerative disease and the major cause of dementia, a chronic loss of global cognitive function, especially memory. AD has been extremely frustrating from a scientific and medical point of view. While there is a great deal of research and it has made impressive progress in understanding the pathophysiology of the disease, we remain without a single coherent “smoking gun” cause of the disease. The problem is (as with other neurodegenerative diseases) that there is a lot happening when brain cells age and die. The trick has been to not only identify markers of AD in the brain, but to understand what role those markers play in the disease. Specifically, are they driving the disease, or are they just a consequence of it?

In medicine there are two main ways to test a causal hypothesis for a correlational marker – can we transfer the disease by transferring the marker, and can we cure the disease by treating the marker? That last question is the ultimate goal of medical research, to find a cure, or at least a disease-modifying treatment. If we can prevent, slow down, stop the progression, or even reverse AD by interfering with one aspect of the disease, then that aspect is likely what’s driving it. But also – we have effective treatments, and everyone is happy.

This is where AD research gets very frustrating. Despite having many pathological clues to follow, researchers have been unable to close the loop – to find a disease-modifying treatment based on our basic science knowledge of AD. This leads to a lot of head-scratching and debate – is AD caused many by the build up of toxic proteins, by impaired neuronal function, by inflammation, or something else? One of the prominent theories of AD is that a major contributor to the disease is a build up of toxic protein, specifically amyloid beta (Aβ). But the Aβ theory has not led to a cure, which has led to many Aβ skeptics in the Alzheimer’s research community.

Continue Reading »

No responses yet

Jul 22 2022

Overconfidence and Opposition to Scientific Consensus

There has been a lot of research exploring the phenomenon of rejection of established science, even to the point of people believing demonstrably absurd things. This is a complex phenomenon, involving conspiracy thinking, scientific illiteracy, group identity, polarization, cognitive styles, and media ecosystems, but the research has made significant progress unpacking these various contributing factors. A recent study adds to the list, focusing on the rejection of scientific consensus.

For most people, unless you are an expert in a relevant field, a good first approximation of what is most likely to be true is to understand and follow the consensus of expert scientific opinion. This is just probability – people who have an understanding of a topic that is orders of magnitude beyond yours are simply more likely to have an accurate opinion on that topic than you do. This does not mean experts are always right, or that there is no role for minority opinions. It mostly means that non-experts need to have an appropriate level of humility, and at least a basic understanding of the depth of knowledge that exists. I always invite people to consider the topic they know the best, and consider the level of knowledge of the average non-expert. Well, you are that non-expert on every other topic.

This is also why humility is the cornerstone of good scientific skepticism and critical thinking. We are all struggling to be just a little less wrong. As a science enthusiast we are trying to understanding a topic at a generally superficial technical level. This can still be a very meaningful and generally accurate understanding – just not technically deep or rigorous. It’s one thing to say – yeah, I get the basic concept of quantum computers, how they work, and why they can be so powerful. It’s another to be able to read and understand the technical literature, let alone contribute to it. Often people get into trouble when they confuse their lay understanding of a topic for a deep expert understanding, usually resulting in them becoming cranks.

Continue Reading »

No responses yet

Jun 30 2022

Is Music Universal?

From a neurological and evolutionary perspective, music is fascinating. There seems to be a deeply rooted biological appreciation for tonality, rhythm, and melody. Not only can people find certain sequences of sounds to be pleasurable, they can powerfully evoke emotions. Music can be happy, sad, peaceful, foreboding, energetic or comical. Why is this? Music is also deeply cultural, with different cultures independently developing forms of music that are very different from each other. All human cultures have music, so the question is – to what extent are the details of musical appreciation universal vs culturally specific?

In Western music, for example, there are minor and major scales, chords, and keys. This refers to the combinations of notes or intervals between them. Music in a minor key tends to evoke emotions of sadness or foreboding, while those in a major key tend to evoke happiness or brightness. Would anyone from any culture interpret major and minor key music the same way? Research suggests that major and minor emotional effects are universal, but a recent study casts a little doubt on this conclusion.

The researchers looked at different subpopulations of people in Papua New Guinea, and both musicians and non-musicians in Australia. They chose Papua New Guinea because the people there share a common musical tradition, but vary in their exposure to Western music and culture. The experiment was simple – subjects were exposed to major and minor music and were asked to indicate if it made them feel happy or sad (the so-called emotional “valence”). Every group had the same emotional valence in response to major and  minor music – that is, except one. The one group that had essentially no exposure to Western culture and music did not have the same emotional reaction to music.

Continue Reading »

No responses yet

Jun 27 2022

Flu Vaccines Associated With Reduced Alzheimer’s Risk

Published by under Neuroscience

A recent large population-based study shows a significant reduction in the risk of developing Alzheimer’s disease (AD) in older adults who received one or more flu vaccines. This follows previous studies showing a similar protective effect for other adult vaccines, and raises interesting questions regarding possible mechanisms.

AD is a degenerative neurological disease which is the most common cause of dementia, which is a syndrome of chronic global cognitive impairment. The prevalence of AD is about 6.5 million people in the US. The risk of developing AD increases with age, with 10.7% of those 65 and older being affected. AD is more than just having dementia, it is a specific disease that can only be confirmed at this time by looking at the brain. There are pathological changes including plaques and tangles. Imaging can also reveal diffuse cortical atrophy (shrinkage of the brain). Electroencephalogram typically shows slowing, indicating reduced cortical activity. There are many markers of AD that can be identified in the blood or spinal fluid, but none are good enough to be used in routine clinical evaluation.

The causes of AD are complex and not yet fully understood. In brief, a lot of stuff happens on the way towards brain cells dying but it’s hard to known which stuff is driving the process and which are a result of the process. It therefore has been difficult to device treatments to slow or prevent progression. For my entire career as a neurologist it seemed as if we were getting close to a significant clinical breakthrough, but we’re still waiting. Tremendous progress has been made, but nothing that amounts to a disease-modifying treatment.

Prevention before the disease becomes clinically apparent would be ideal. We know that controlling blood pressure and other markers of cardiovascular health are extremely important in reducing the risk of AD. We also know that physical exercise is important, as well as keeping mentally active. Sometimes, however, it is difficult to separate preventive measures that actually delay or slow the onset of AD vs those that mask the onset through creating a higher baseline of cognitive function. Regardless, all of the above are good lifestyle choices.

Continue Reading »

No responses yet

Jun 17 2022

In-Group Cognitive Bias

Published by under Neuroscience

Human nature (and it’s pretty clear that we do have a nature) is complex and multifaceted. We have multiple tendencies, biases, and heuristics all operating at once, pulling us in different directions. These tendencies also interact with our culture and environment, so we are not a slave to our biases. We can understand and rise above them, and we can develop norms, culture, and institutions to nurture our better aspects and mitigate our dark side. That is basically civilization in a nutshell.

In fact, many scientists believe that humans also domesticated themselves – applied selection pressures that favored people who were less aggressive, more pro-social. It’s hard to prove this is true, but it does make sense. As civilization took hold, people whose temperament were better suited to that civilization would have a survival advantage.

Psychologists, however, have long documented that pro-social behavior in humans is a double-edged sword, because we only appear to be pro-social toward our perceived in-group. Toward those who we believe to be members of an out-group the cognitive algorithm flips. This is referred to as in-group bias, and also as “tribalism” (not meant as a knock against any traditional tribal culture). Negativity toward a perceived out-group can be extreme, even to the point of dehumanizing out-group members – depriving them of their basic humanity, and therefore any moral obligation to them. That appears to be how our brains reconcile these conflicting impulses. Evolutionary forces favored people who had a sense of justice, fairness, and compassion, but also needed a way to suspend these emotions when our group was fighting for its survival against a rival group. At least those groups with the most intense in-group loyalty, and the ability to brutalize members of an outgroup, were the ones that survived and are therefore our ancestors.

Increasingly neuroscience can investigate the neuroanatomical correlates of psychologically documented phenomena. In other words, psychologists show how people behave, and then neuroscientists can investigate what’s happening in the brain when they behave that way. A recent study looks at one possible neural mechanism for in-group bias. They recruited male subjects from the same university and then imaged their brain activity while they retaliated in a game against targets from their university and targets from a rival university. The researchers used rival universities, rather than more deeply held group identities (such as nationality, race, religion, political affiliation) to avoid undue stress on the subjects. Yet even with what they considered to be a mild group identity, the subjects showed greater activity in the ventral striatum when retaliating against out-group targets than in-group targets.

Continue Reading »

No responses yet

May 26 2022

How Memories Are Linked

Published by under Neuroscience

Memory research, both at the psychological and neurological level, is fascinating, partly because memories are so essential to who we are. We often don’t perceive the underlying mechanisms by which memories are formed, stored, and recalled, but they dramatically affect our mental life. Further, being aware of how our memories work is a critical part of neuropsychological humility – human memory is not perfect, it’s not like a tape recorder, it is a dynamic and flawed process. For example, different aspects of a memory and different memories are linked together, but these connections can be jumbled. We may fuse the detail of one memory to another, alter details completely, and even remember things that happened to someone else as if they happened to us.

This is partly because memory did not evolve to be a perfect recorder of our life experiences, but rather to create a meaningful and adaptive narrative of our past. One critical component of the adaptive nature of memories is that our brains can link different memories together, because they apparently have a meaningful connection. A recent study tries to elucidate one aspect of this process, and as a result may have turned up a clinically useful bit of information.

For a little background, our brains function as massively parallel processors. One of their core functions is to make associations between different things – when we remember one thing that triggers other memories, including details about the original memory but also other memories. Our brains are association machines. This is not only intrinsic to how we remember but how we think. Much of literature, storytelling, metaphor, and creativity derives from association. How does this work at a neuronal level? It’s safe to say that it’s complicated, but the researchers were trying to elucidate one tiny piece of the picture.

Continue Reading »

No responses yet

May 23 2022

EVs and Range Anxiety

Demand for electric vehicles (EVs) is increasing, but still there is lingering hesitancy to make the switch to EVs. Sales of EVs have been increasing geometrically over the last decade, with global sales reaching 6.6 million in 2021, compared to 66.7 million total vehicles sold. While this trend is encouraging, there is still a long way to go and the global warming clock is ticking. So what barriers remain to more complete adoption of EVs?

Up front cost is still an issue, but this has been largely mitigated by the availability of more EV options that are in the range of comparable internal combustion engine (ICE) vehicles. Also the total cost of owning an EV is cheaper. According to a 2020 analysis:

For all EVs analyzed, the lifetime ownership costs were many thousands of dollars lower than all comparable ICE vehicles’ costs, with most EVs offering savings of between $6,000 and $10,000. While new EVs were found to offer significant cost savings over comparable ICE vehicles, the cost savings of 5- to 7-year-old used EVs was found to be two or three times larger on a percentage savings basis.

That was also before the recent spike in gasoline prices, and such spikes are not rare and likely to happen during the course of owning an EV. I wrote recently about the local health benefits of reducing pollution. I own an EV and I can also attest to other practical benefits. The driving performance is excellent, better than any ICE car I have driven. I can “fill up” at home and never have to take the car to a gas station. There is also limited routine maintenance – no oil changes or all the other things that go with an ICE. Because of regenerative braking the brake pads also last much longer. The tires are really the only thing that require attention. It is simply a superior car-owning and driving experience, and the money saving is nice.

Continue Reading »

No responses yet

« Prev - Next »