September was National Recovery Month. And in September, science writer Megan Ray Nichols reached out. Megan made an infographic about the research on and differences between addiction and habit. It’s really interesting and well-designed! Check out the infographic and the sources below. Continue reading Addiction Vs. Habit: An Infographic
Michael Bishop outlines a network theory of well-being in which well-being is constituted by positive causal networks and their fragments (2012, 2015). ‘Positive’ refers to — among other things — experiences that have positive hedonic tones, the affirmation or fulfilment of one’s values, and success in achieving goals. So according to Bishop’s view, we flourish when certain positive causal networks are robust and self-reinforcing. For example, something good happens to us and that improves our motivation and mood, which then helps us achieve more, which improves our motivation and mood even more, and so on.
Bishop’s network account musters philosophical rigor by providing a systematic and coherent account of wellbeing that satisfies many common sense judgments about well-being. But lots of philosophical accounts can do that. So Bishop’s account does even more. It unifies and makes sense of a huge swath of the science. This provides some reason to think that Bishop’s account is superior to its competition.
So what’s this got to do with exercise and neuroscience?
I am largely persuaded by Bishop’s arguments for the network account of well-being, so I will skip my criticism of the project. Rather, I will add to it. Specifically, I will show how well is makes sense of the neuroscience. While I will not be able to review all of neuroscience, I can accomplish a more modest goal. I can review one part of neuroscience: the effect of exercise on the brain.
There is a wealth of evidence suggesting that regular physical activity and exercise forms an important part of one’s positive causal network of well-being by, among other things, increasing positive affect (Harte, Eifert, and Smith 1995), increasing confidence (Klem, Wing, McGuire, Seagle, and Hill 1997), reducing stress, relieving depression (Blumenthal et al 1999; Motl et al 2005) and preventing more than a dozen chronic diseases (Booth, Gordon, Carlson and Hamilton 2000; see also Biddle, Fox and Boutcher 2000 for a review of relationships between exercise and well-being). The mechanisms for all of these results are not entirely clear. But neuroscience is providing, in broad strokes at least, some clues about the mechanisms that can explain, in part, why exercise produces a series of positive effects in a well-being network (e.g., Meeusen 1995, Farooqui 2014).
The Positive Effects in the Brain
Let’s start with how exercise produces direct positive effects in the brain. Firstly, exercise and regular physical activity directly improve the brain’s synaptic structure by improving potentiating synaptic strength (Cotman, Berchtold, Christie 2007). Secondly, exercise and regular physical activity strengthen systems that underlie neural plasticity—e.g., neurogenesis, the growth of new neural tissue (ibid., Praag et al 2014). These changes in the brain cause “growth factor cascades” which improve overall “brain health and function” (ibid.; Kramer and Erickson 2007).
Now consider how exercise has indirect positive effects in the brain by producing ancillary positive circumstances. Generally speaking, “exercise reduces peripheral risk factors for cognitive decline” by preventing—among other things—neurodegeneration, neurotrophic resistance, hypertension, and insulin resistance (ibid.; see also Mattson 2014). By preventing these threats to neural and cognitive health, exercise is, indirectly, promoting brain health and function.
Positive Causal Networks
It requires no stretch of the imagination to see how these positive effects will reinforce positive causal networks and thereby increase well-being. Even so, I will do you a favor by trying to demonstrate a connection between exercise, the brain, and the larger network of well-being.
We have already seen how exercise results in, among other things, increased plasticity. And increased plasticity results in improved learning (Geinisman 2000; Rampon and Tsien 2000). Also, the increased plasticity that results in improved learning can produce other positive outcomes: increased motivation, increased opportunities for personal relationships in learning environments, etc. (Zelazo and Carlson 2012, 358). Further, increased motivation and social capital can — coming full circle — result in further motivation (Wing and Jeffery 1999).
That right there is what we call a self-reinforcing positive causal network or positive feedback loop. And that, according to Bishop, is how we increase well-being (see figure 1).
This causal model shows how the neuroscience we just discussed implies a causal network. The nodes and causal connections in this model show how well-being is a matter of positive causal networks.
3. What about Ill-being?
Obviously, I’ve only mentioned the neuroscience of well-being. But if we want to promote well-being, then we also have to decrease ill-being, right? Right. And once again, the network theory of well-being will fit nicely with the research on ill-being. For example, the research on emotion regulation (see Livingston et al 2015) implies some causal networks that can inhibit ill-being. The same can be said of the research about using deep brain stimulation in treatment-resistance depression (Bewernick et al 2010; Lozano et al 2008; Mayberg et al 2005; Neuner et al 2010).
4. A Concern: Fitness
You might object by positing that Bishop’s theory of well-being will not fit neuroscience as well as it fits positive psychology. This objection can be dismissed in a few ways. Here are two ways.
First, we can safely accept that Bishop’s network theory of well-being will not fit neuroscience as well as it fits positive psychology. After all, Bishop’s network theory was designed to fit positive psychology, not neuroscience. It’s hardly a fault for a theory to not do what is was not intended to do.
Second, neuroscience is a larger domain than positive psychology. So of course it is harder for a theory to fit it. Allow me to explain. As the domain of discourse increases in scope, it becomes increasingly difficult for us to find a theory that fits all of it. So, because neuroscience is a larger domain than positive psychology, the challenge of providing a theory that fits neuroscience is always more difficult than providing a theory that fits positive psychology. So the fitness objection doesn’t necessarily reflect badly on Bishop’s theory. It might only reflect a difference between positive psychology and neuroscience.
Let me summarize. I mentioned a few cases in which Bishop’s theory of well-being can unifies and makes sense of neuroscience. Then I proposed a few more cases in which Bishop’s theory might do the same. And then I addressed a skeptical worry about the project I propose. So Bishop’s theory of well-being can accomplish even more than Bishop intended.
Kouider et al have recently reported that infants’ cortical activity (when viewing faces) is isomorphic to that of adults who consciously perceive faces. They conclude that conscious perception develops between 5 and 15 months of age. After reading their paper, I want to consider a different conclusion. Perhaps Kouider et al didn’t find a marker of conscious perception. Maybe they found a marker of unconscious perception.
I will be at the University of Utah presenting a paper at the Intermountain Philosophy Conference tomorrow entitled “Neurobiological Correlates of Philosophical Belief & Judgment: What This Means for Philosophy.” An abstract is below. The conference website is here.
It is becoming increasingly common to find journals publishing articles that demonstrate psychological correlates (e.g. Adelstein, Deyong, Arvan) and biological correlates (e.g. Harris, Hsu, Stern) of various self-reported beliefs and judgments. It is perhaps most common to find articles reporting the correlates of political beliefs and judgments (e.g. Amodio, Arvan, Hatemi, Kanai, Tost). This paper sets out to show that philosophical beliefs are also worth experimental attention. But that is not all: I hypothesize that variations in peoples’ biology—perhaps their neurobiology in particular—could correlate with variations in their proclivity towards or aversion to particular philosophical beliefs and judgments. In the first section of the paper, I lay out what we might expect to learn about our philosophical beliefs from our neurobiology. Before I conclude that philosophical beliefs (or philosophical cognition) are worthy of experimental attention, I mention some philosophical and methodological concerns and some objections to the suggested research. I am careful to note along the way that while many of the conclusions reached by this research could be illuminating, we none of it should be devastating to philosophy. That is not to say that the research wouldn’t inspire some methodological reform (e.g., whether and how philosophers appeal to intuition or exploit certain language), but it would by no means “end” philosophy.
A couple month’s ago, I was at a conference where Anthony Jack proposed a very interesting theory: maybe we have two neural systems (Task Positive Network [TPN] and Default Mode Network [DMN]) that produce conflicting intuitions about some age-old philosophical puzzles. These conflicting intuitions lead us to get stuck when thinking about these puzzles (e.g. the hard problem of consciousness, the explanatory gap, or qualitative consciousness) are the result of conflicting intuitions (Jack et al 2013).
I was struck by Jack’s presentation for two reasons: (1) I was presenting a poster with a similar motivation at the same conference and (2) I have long been interested in a biological examination of (academic) philosophers.
This link is a poster about philosophers’ brains that I presented at the Towards a Science of Consciousness Conference in Tuscon—I gave a talk based on this poster at University of Utah. Use the link to see a full-size PDF that will allow you to zoom ad nauseum without the blurriness—vector graphics are so cool!
We should not be surprised if some of the differences between philosophers views correlate with differences between philosophers’ brains. I list a handful of neurobiological differences that already correlate with philosophical differences among non-philosophers. It’s not obvious what we should glean from the possibility that philosophers’ brains could differ as a function of their views. After all, it might be that studying certain views changes our brain. That would not be surprising or concerning, really. But if it were the other way around — e.g., that structural/functional differences in brains predisposed us towards some views and away from other views — then that might be concerning. What if academic philosophy is just an exercise of post hoc rationalization of the views that philosophers’ brains are predisposed toward? Of course, it’s entirely possible that causation works in both directions. But even that could be concerning because that is compatible with self-reinforcing feedback loops. For instance, perhaps we are neurally predisposed to certain views, so we study those views which further predisposes us toward that view (and away from its alternatives). But these questions are getting ahead of the evidence. Hopefully, the neuroscience of philosophy will provide some answers. Until then, check out the poster to see what questions the research has already answered.