What causes bad moods? Why do we sometimes slip into angry fits and melancholy torpors? In general, happy moods have easy explanations – we know why we’re elated. But a bad mood often seems to arrive out of the blue, a gloomy weather pattern that settles in from everywhere all at once. All of a sudden, we find ourselves pissed off without a good reason, which only makes us more pissed off.
[...]
A brand new paper, published in the Journal of Consumer Research, extends this link between self-control and anger, even as it complicates the ego-depletion model. In a series of clever studies, the Northwestern psychologists David Gal and Wendy Liu demonstrate that the exertion of self-control doesn’t just make it harder for us to contain our own anger – it also make us more interested in watching anger-themed movies, or thinking about anger-related information, or looking an angry facial expressions. In other words, acts of self-control haven’t just exhausted the ego – they actually seem to have pissed it off.
My favorite experiment involved movies. Two hundred and thirty nine subjects were given a choice between a virtuous apple and a hedonistic chocolate bar. (A slim majority chose the apple.) Then, they were offered a selection of movies to watch, from Anger Management (an anger themed film) to Billy Madison (a non-anger themed film.) Interestingly, students were significantly more likely to choose the angry films if they’d first chosen the apple. And it wasn’t just films: another experiment found that people who exercised financial restraint – they chose a gift certificate for groceries over one for spa services – were more interested in looking at angry faces.
What’s driving this effect? Gal and Liu argue that the preference for angry stuff is not simply a result of ego depletion. Instead, they speculate that self-control is inherently aggravating. Perhaps choosing the apple annoys us because our goals have been thwarted – we really wanted the candy bar – or maybe we’re pissed because we feel that our sense of autonomy has been diminished. (If we weren’t so constrained by societal norms and expectations, we would have gorged on chocolate.) The point is that the labor of self-control directly inspires our tendency towards anger, and not indirectly via a worn down prefrontal cortex.
Two hundred and thirty nine subjects were given a choice between a virtuous apple and a hedonistic chocolate bar.
This exemplifies a fallacy that is almost ubiquitous in psychological experiments, and runs right through this paper. The subjects were not offered a choice between a virtuous apple and a hedonistic chocolate bar. They were offered a choice between an apple and a chocolate bar (or of declining either). Personally, I eat about 10 to 20 times (by weight) as much apples as chocolate, because that it what it pleases me to do. Likewise, a choice between groceries and spa services is not a choice between restraint and indulgence. Besides which, any subject smart enough to look at what the offered transaction actually is (which surely includes everyone on LessWrong?) will have the sense to choose the voucher for something they would be spending money on anyway, making it exactly equivalent to being given that sum of money to direct in any they wish. (I see from the paper that they were not actually offered a voucher, but the chance to win one in a raffle. I suppose that keeps the experimental costs down. I wonder if any prizes were actually awarded?)
The fallacy being committed here is of attributing to a stimulus an imagined response of your subjects. To this way of thinking, apples are "virtuous", chocolate is a "temptation", and a spa session is a "luxury". None of these things are true. How the subjects respond to these offers depends on their own purposes, whose existence experimental psychologists generally ignore. They prefer to imagine that they are reaching into the heads of people, tweaking knobs and reading dials. This is pseudoscience and superstition.
Inevitably, the results are the usual statistical mush.
self-control is inherently aggravating
Thanks for pointing it out (by science!)-- a lot of people who wish to perfect their personality should know it. I didn't consciously know it, but developed a mental discipline of acknowledging anger in my tormented teens anyway. People who hold intuitive ideals about "perfection of humanity/personality" should learn neuroscience, lest they suppose that things they ought to do (control themselves) must bring happiness. They may be confused when they experience that anger, and either conclude that they are born sinful/defective, or selfish/negative emotions are to be done away with to achieve perfection.
I really want say: It's OK to feel hurt if you didn't get what you want, even if that's because you did what you should/must. Those who try to make humans completely ethical/self-controlled are turning us into something not human.
But what did I just say? Surely that's an excuse for being impulsive? I want what I want, and I don't want to be called unethical for that. And that humanness part -- if doing whatever you end up deciding by taking "liking, wanting and learning" into account seems to be functional in the past, in meatspace, can't it be utterly disastrous when we have access to Singularity-level power? Shouldn't we sever the lower impulses and go with ethics instead? (But is it, um, fun?) I don't know what should I feel...Hope the one that comes up with FAI first is not going to program it to value ethics strictly above fun...
Very good post. The difference between liking and wanting is also discussed in Are Wireheads Happy?, which probably merits a link somewhere in the post (perhaps the "pleasure electrodes" portion).
I hadn't read Yvain's post before, thanks. It's very relevant. I've linked it under self-help implication #1.
More serious brain injuries associated with more life satisfaction
Psychologists investigating the well-being of patients with an acquired brain injury (ABI) have documented a curious phenomenon, whereby the more serious a person's brain injury, the higher their self-reported life-satisfaction.
[...]
Perhaps the most curious finding was that participants who'd sustained more serious injuries tended to report being more satisfied with their lives. This association was mediated by the social and identity factors - that is, participants who'd sustained a more serious injury also tended to identify more strongly as a survivor, and to have more social support and improved relationships.
David Pearce commented on this post on Facebook:
As an illustration of how much we still don't know: The mu-opioid receptor agonist remifentanil induces acute dysphoria irrespective of its analgesic properties.
Selective activation of the mu opioid receptors by a full mu opioid receptor agonist is the closest recipe we have for pure bliss without desire. But this activation needs to be in the ultimate hedonic hotspots of nucleus accumbens and posterior ventral pallidum. What is the gene expression profile of these cells? Why are they so special?
and more importantly, how do I wirehead using them instead of the aforementioned wanting cells.
Unfortunately, the interaction between these components is extraordinarily complex, and many puzzles remain.
This seems pretty important regarding CEV?
What about if I don't want to do something, don't like to experience doing it but feel that I am morally obligated to do it? In what category does such a drive fall, or is one just confused in that case? It seems to me that it also has to do with pleasure, but a solely negative incentive. One might feel worse not doing it but one won't feel good either. For example, if you kick the fat man onto the rails facing the Trolley problem you'll feel bad but maybe not as bad as if you didn't do it. Or is such thinking not part of the wanting/liking/learning system at all? The problem with this is, what is it that CEV is going to extrapolate, wanting/liking or what we think we ought to want? It seems that Yudkowsky only advocates CEV if it turns out that humanity decides to do what it ought to do and not what it might on some other level want to do:
...generic procedures meant to prevent CEV from running if 80% of humanity turns out to be selfish bastards... (Eliezer Yudkowsky 14 February 2011 06:43:09 AM)
An example would be what humanity wants to do with the limited resources in the universe versus what it ought to do with them. What if it turns out that humanity wants to waste all resources to support a single galactic civilisation for a few billion years rather than 100 times as many beings for as long as physically possible but with a reduced average amount of pleasure?
So is the SIAI going to extrapolate our reward system or high-level ethical decision making? Decision-utility versus experience-utility?
This post was a pleasure. Now I know how you got so wise on this subject - your number one source is Kent Berridge.
The scientific approach to self-help suggests that a better understanding of who we are can help us achieve happiness and other goals. Most centrally, it will be helpful to understand our brains, because it is our brains that generate happiness and goals.
In particular, I'd like to explore the neuroscience of pleasure and desire. Today's post covers the neuroscience of pleasure; the next post will cover the neuroscience of desire. After each post I'll consider some of the implications for self-help. In a later post, I'll consider how this research can inform the pursuit of Friendly AI.
The last decade has seen the arrival of affective neuroscience: the study of the neural mechanisms behind emotion, including pleasure and desire.1 Most questions remain unanswered, and experts disagree on many specifics,2 but there are some things we can state with confidence. We begin with the reward system in the brain.
The reward system consists of three major components (image)3:
Unfortunately, the interaction between these components is extraordinarily complex, and many puzzles remain.5
I'll share two examples of our ignorance. First: pleasure electrodes. For decades, it was thought that electrical stimulation of certain structures caused pleasure, because rats and humans would self-administer this stimulation hundreds or thousands of times each hour if allowed to do so.6 But a careful reading of the transcripts reveals the causation of wanting, not liking. Sometimes, the cause was even an unpleasant nervousness.7 Though, there are a few exceptions where liking was produced.8
Second: dopamine. For decades, experts thought dopamine was 'the pleasure chemical'.9 But this is probably false.10 Lack of dopamine does not impair 'liking' reactions.11 And in humans, perceived pleasure is not reduced by loss of dopamine.12 Dopamine has a big role in wanting, instead.13
Today we focus on 'liking' or pleasure.
Thoughts and sensations are not intrinsically pleasurable. Rather, the reward system must paint them with a 'hedonic gloss' to make them 'liked'.14 Food and sex are reliably pleasurable for obvious Darwinian reasons.15 These 'fundamental pleasures' use the same brain structures as 'higher-order pleasures' like social pleasures, art, money, and altruism.16
The basic structures which produce pleasure are shared by other mammals (for Darwinian reasons), and other mammals exhibit liking processes in the brain.17 It's not clear how similar their subjective experience of pleasure is to our own, though. Humans do have unique cognitive, representational and 'savoring' capacities,18 among others.
Much research concerns 'hedonic hotspots' in the brain. A hedonic hotspot might be a necessary cause of pleasure (pleasure doesn't occur without it; e.g. the ventral pallidum), a sufficient cause of pleasure (if activated, pleasure occurs; e.g. the nucleus accumbens), or it may code for pleasure (its activation correlates with pleasure, but might be either a cause or effect of pleasure, or both; e.g. the orbitofrontal cortex and ventral pallidum). A substrate may play multiple roles, or it may code without causing, or it may be a sufficient cause without being a necessary cause.19
We know thousands of specific things about pleasure and the reward system, but we don't yet understand pleasure on a systems level. We don't know how to integrate these thousands of bits of information into a cohesive theory of how pleasure works.
Many have tried, of course. Here is Tim Schroeder's attractively simple theory of pleasure:
To be pleased is (at least) to represent a net increase in desire satisfaction relative to expectation; to be displeased is to represent a net decrease in desire satisfaction relative to expectation. Intensity of pleasure or displeasure represents degrees of change in desire satisfaction relative to expectations.20
But this is too simple. Though pleasure often results from experiencing more satisfaction than expected, there are many other sources of pleasure,21 and pleasure can occur in animals that lack representational capacities or expectations, for example anecephalic infants and animals with most of their brains removed.22
Among neuroscientists, there are many overlapping theories of pleasure, which are often not mutually exclusive.23 Rather than survey them all, let me jump to the self-help advice: what can brain science teach us about pleasure and how to get more of it?
The neuroscience of pleasure is most useful when designing new drugs or performing neurosurgery, but there are a few self-help recommendations we can draw from the field:
This is a short list, but additional self-help recommendations can be gleaned after we build on this knowledge to discuss the neuroscience of desire, which we will cover next.
1 LeDoux & Phelps (2000); Berridge (2003a); Davidson et al. (2003); Damasio (2004); Rolls (2005); Feldman & Wager (2006); Kringelbach (2005); Kringelbach & Berridge (2009a, 2009b).
2 Kringelbach et al. (2009).
3 Berridge & Kringelbach (2008); Berridge et al. (2009); Berridge (1996); Berridge & Robinson (1998); Pecina et al. (2003); Camerer (2006); Kringelbach & Berridge (2010b). Some experts will talk as if there is no such thing as unconscious pleasure (Kringelbach et al. 2009), but this is only a manner of speaking adopted to respect the folk understanding of conscious pleasure, for they acknowledge the same unconscious hedonic processes that other researchers do (Winkielman & Berridge 2004; Winkielman et al. 2005; Schooler & Mauss 2009). Likewise, though ever researcher may not use the liking / wanting / learning scheme, I haven't found any major expert who disagrees with the minimal factual claims presupposed by that scheme. Experts agree that pleasure, motivation, and learning are distinct components of the reward system in the brain.
4 The neural processes that apply the 'hedonic gloss' to sensations and cognitions seem to be a particular pattern of excitation of neurons in a hedonic hotspot in the ventral pallidum (Tindell et al. 2005; Aldridge & Berridge 2009), though other brain structures may play a role as well, in particular the nucleus accumbens (Smith et al. 2001), the orbitofrontal cortex (Kringelbach 2009), and perhaps the perigenual anterior cingulate cortex (Schroeder 2004, ch. 3). Commonly measured 'surface' pleasure reactions are (1) subjective report in humans, and (2) particular facial expressions in human adults, human infants, chimpanzees, and rats (Smith et al. 2005). See videos here.
5 Baldo & Kelley (2007); Balleine & Kilcross (2006); Balleine et al. (2007); Beaver et al. (2006); Burke et al. (2009), Di Chiara & Bassareo (2007); Evans et al. (2006); Everitt & Robbins (2005); Izard (2007); Kuhn & Koob (2010); Panksepp (2007); Salamone et al. (2007); Schultz (2006); Stoeckel et al. (2008); Van Leijenhorst et al. (2010); Volkow et al. (2006); Voon et al. (2010); Wise (2006); Kringelbach & Berridge (2010a).
6 Delgado (1969); Heath (1972); Sem-Jacobsen (1976).
7 Berridge (2003b); Pecina et al. (2006); Smith et al. (2009).
8 Morgan et al. (2006).
9 Hoebel et al. (1999); Shizgal (1999); Wise & Bozarth (1985).
10 Smith et al. (2009); Berridge (2007); Robinson & Berridge (2003).
11 Berridge & Robinson (1998); Berridge et al. (1989); Robinson et al. (2005); Pecina et al. (1997).
12 Sienkiewicz-Jarosz et al. (2005); Brauer et al. (2001); Leyton et al. (2005); Leyton (2009).
13 Berridge (2007).
14 Frijda (2006, 2009); Aldridge & Berridge (2009); Ryle (1954).
15 Cabanac (2009); Kringelbach (2005, 2009); Rolls (2005); Schulkin (2004).
16 Kringelbach (2005, 2009); Pecina et al. (2006); Small et al. (2001); Gottfried (2009); Kahneman et al. (2004).
17 Steiner et al. (2001); Berridge (2000); Kringelbach (2008, 2009); Smith et al. (2009); Calder et al. (2007).
18 Barrett et al. (2007); Frijda (2006); Frijda & Sundarajan (2007); Gilbert & Wilson (2007).
19 Berridge & Kringelbach (2008); Smith et al. (2009).
20 Schroeder (2004), p. 94.
21 Smith et al. (2009); Kringelbach & Berridge (2009b).
22 Steiner (1973); Steiner et al. (2001); Goltz (1892); Miller & Sherrington (1915); Grill & Norgren (1978). It must be noted that my summary is a bit unfair to Schroeder: Schroeder is offering a theory only of conscious pleasure, which may indeed require the representational capacities unneeded for unconscious 'liking.' Still, it remains the case that there seem to be many other causes and implementations of pleasure than representations of a positive difference between actual desire satisfaction and expected desire satisfaction. But Schroeder's theory is not, as far as I can tell, decisively falsified by the data.
23 See Dickinson & Balleine (2009) for a comparison of theories. Some leading theories are: the somantic marker hypothesis by Damasio (1996), the hedonic interface theory by Dickinson & Balleine (2009), the common currency theory of Cabanac (1992), and the multiple-components theories of Berridge, Kringelbach, and others: see Berridge & Kringelbach (2008); Kringelbach (2008).
24 Smith et al. (2009); Tindell et al. (2005); Smith et al. (2007); Berridge et al. (2009).
25 Smith et al. (2009); Dickinson & Balleine (2009).
26 For example, Damasio (1994), p. 263.
27 Burke et al. (2009); Aldridge & Berridge (2009).
28 Berns et al. (2006).
29 Gard et al. (2006).
30 Green et al. (2009).
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