emotions

Discrete versus dimensional models of emotion?

Eliza Bliss-Moreau
Eliza Bliss-Moreau

Over the last number of months as an Associate Editor at Emotion, as well as a reader of the literature, I have seen an increasing number of scholars refer to “discrete emotion models” and pit them against “dimensional emotion models” in order to set up a primary hypothesis and its alternative.  This is a false dichotomy.  My challenge as an editor is that I have not been able to find a singular “quick read” piece of writing in the literature articulating why a discrete versus dimensional contrast doesn’t make sense (although there are longer papers on this that do make this point such as this, this, this, and this – if you know of others that are near and dear to you, send them my way).  I did a quick – entirely nonscientific – review of papers with the keyword “emotion” and “discrete or dimension or dimensional” published in 2017 and 2018 and there is some evidence that this is a problem in the published literature as well.  My first take was “I should write a manuscript about this”, and I may, ultimately. My goal here, however, is not to call people out for this analytical problem per se but to provide an explanation as to why pitting discrete emotion models against dimensional emotion models is logically problematic, so that folks can fix it if it is in their writing (or thinking) or not make it in the first place. I don’t see any way around that goal if I were to undertake writing a manuscript which would require appropriate scholarly referencing.  So, writing a blog post seemed like a good option.

The problem
There are lots of theories and models of emotion that focus on discrete emotions – how they come to be, their outputs, their functions, and so on.   They vary widely in their hypotheses about all of those features of emotion. But there is no dimensional theory of emotion.  Dimensions  – typically valence and arousal –  are characteristic of affect [i], not emotion.  According to a number of the major theories in our field, affect is thought either to be the causal foundation of emotion or one of the most important components of emotion.  Saying that affect is a causal foundation or critical component of emotion is very different, however, from saying that affect is emotion – and so, theories of emotions which recognize differences between affect and emotion are not reductionist about emotions.  According to these theories, whatever else emotion is, it is something “more” than just affect. It is therefore a mistake to talk about theories of emotions as if they are dimensional.  As a result, there is no way to pit “discrete emotion models” against “dimensional emotion models” because a) there is no dimensional emotion model, only dimensional affect models and b) emotion theories that hypothesize that multiple dimensions of affect underlie emotions in some way or another frequently hold that these emotions can be separated into distinct types and kinds, and therefore are, metaphysically speaking, discrete entities.

The background
It goes without saying that there are many different theoretical and methodological approaches to the study of emotion. Over the last decade or so, two types of theories have dominated discussion and study (despite both being around for much longer) – what we call the Classic View of Emotion (CVE) [ii] and Theories of Constructed Emotion (TCEs).  I use this terminology with very specific intentions, not just as shorthand labeling to differentiate my writing from that of other scholars.

The CVE says that emotions are precipitated by events and then produce a stereotypical set of outputs in the face, voice, autonomic/peripheral nervous system, behavior, and, or brain.  There is a predictable mapping between the types of events that cause emotions and specific emotions. Further, each emotion is thought to have some sort of specific pattern of physiological and behavioral outputs. Because of this, to understand the emotion state of another individual, an observer (who could be the self) can “read” the outputs and, because the relationship between the outputs at the emotion causing them is mapped, infer the identity of the emotion causes the relevant outputs.

The interesting unit of analysis from the CVE can be at any step of the process – the event that causes the emotions, the process by which the effects of the event are translated into the emotion, the phenomenological experience of the emotion, the process by which the emotion generates to the outputs, the type of outputs generated by the emotions.  CVEs stipulate that some special set of, or number of, emotions cannot be reduced to more fundamental or basic parts. This belief is reflected in the moniker of one type of CVE – “basic” emotion theory.

“Basic” emotion theories typically stipulate that a small set of emotions (e.g., 5 or 6) are unique kinds.  This means that they are held by the theory to be fundamental or basic [iii], irreducible, and have a modular neurobiological architecture [iv].  These theories sometimes stipulate that more “complex” emotions (e.g., guilt) may be built via combinations of basic emotions, but even those more emotions must follow the event–>emotion–>output schema according to this theory (a view articulated here, for example). Basic emotion theories argue that relationships between events, emotions, and outputs is biologically hardwired and evolutionarily conserved; these assumptions have guided investigation into the neurobiological basis of emotion (e.g., in nonhuman animals, and in humans) and evolutionary emergence of emotion (for example).

Basic emotion theory is arguably the dominant theory that embodies a CVE, but it is not the only theory, hence my use of “CVE” and not “Basic Emotion Theory” (or something similar) to name this perspective.  For example, most appraisal theories embrace a CVE insofar as they evaluate the specific pattern of cognition (called appraisals) that people make following events that lead to emotion – that is the process by which the event translates to emotions.

CVEs do say there are discrete emotions, whether they stipulate that a small set of emotions is biologically basic and hardwired or focus on the process by which an event precipitates an emotion or even the numbers of discrete emotions that exist.  The unit of analysis is typically specific, discrete emotions and these emotions are thought to be the source of the lion’s share of variance in outputs.  These are the theories, I believe, that scholars think they are referring to when they discuss “discrete emotion models” because of their emphasis on specific emotions (like happiness, sadness, fear, disgust, elation, and so on). Further, CVEs do not typically discuss or evaluate the importance of valence and arousal – the dimensions of affect.

Valence and arousal are the dimensions of affect, which, according to TCEs forms the basis of discrete emotions.  TCEs stipulate that emotions are not hardwired modules. Instead, TCEs say that each emotion is a causal by-product of a complex interaction of more basic parts, and that these parts can vary dramatically depending on age, behavioral context, cultural context, conceptual knowledge, and any number of other important physiological and cognitive factors [v].  Nevertheless, TCEs still recognize that emotions are discrete things. TCEs differ to some degree in the ingredients that they think are critical for the emergence of discrete emotions – hence Theories of Constructed Emotion and not Theory of Constructed Emotion.  But all TCEs hold that affect is a critical ingredient.

Affect is a state that is characterized by some degree of valence (hedonics, pleasantness to unpleasantness) and arousal (physiological activation) and can, but need not be, felt consciously.  People can report on their affect (“I feel good” or “I feel bad”) or, people can report on their emotions and affective information can be extracted from those reports (e.g., one characteristic of happiness is a good or pleasant feeling). That is, affect can be organized according to dimensions (valence and arousal). That is the case because discrete emotions are organized in a systematic way with regards to valence and arousal.  Happiness?  Positive valence, just slightly activated/aroused.  Depression?  Negative valence, very deactivated.  Fear, anger, disgust?  Very negative, very activated/aroused, and so on.

TCEs say that affect is an essential component of emotion, but they do not say that affect is emotion – and so they do not reduce emotion to affect. According to TCEs, a discrete emotion has affective components, but the affective states that are components of emotions are not alone sufficient to determine the identity of the emotion of which they are part. For example, there are a slew of negative, high arousal emotions which share a negative, high arousal affective state but are not the same emotion – think anxiety, disgust, anger, and fear.  The same affective state can thus be part of a number of discrete emotions depending on the context, what the person knows about emotion, past experiences, the language the person speaks, social norms, and so on.  As a result, it does not follow to say that emotions, according to TCEs, are (or can be described by) dimensions. Scholars guided by TCEs, just like those guided by CVEs, study discrete emotions – but they may be equally likely to study the various other ingredients that go into cooking up emotions, including affect.

Why does the distinction between discrete emotions and the dimensions of affect matter?
It is important to be clear about whether we are testing hypotheses about emotions (which nearly everyone agrees are discrete entities) or testing hypotheses about affect (which everyone agrees can be analyzed as falling into at least two continuous but bounded dimensions), or testing hypotheses about some combination of the two–for example, when we ask whether (discrete) emotions or (degrees of the dimensions of) affect capture more of the variance in a given situation. Keeping this distinction in mind can help us develop strong, testable hypotheses about the nature of emotion.

For example, the goal of my lab is to understand some of the biological mechanisms that generate the emotions – and we do that work largely in nonhuman animals.  While there is huge debate about the nature of nonhuman animal emotions, I have argued that affect is species nomothetic – at least in mammals who share a similar central-to-peripheral nervous system structure.  If this is the case, and if a given behavioral or physiological phenomenon is driven by affect and not discrete emotions, then we can hypothesize that it has a homolog in nonhuman animals.

Another issue in the nonhuman animal literature that appears regularly is that scientists will make strong claims about animals’ abilities to perceive emotion stimuli when they are actually testing an affect hypothesis.  For example, in a recent study, when goats were shown pictures of human faces generating behaviors typically associated with anger and those typically associated with happiness, goats spent more time investigating the “happy faces”.   The take home message, amplified by the media, was that a) goats understand human emotions or “goats can read human emotions” and b) “goats prefer happy people”.  That may very well be true, but given the experiment as conducted, there’s actually no way to determine whether goats prefer happy people or simply pleasant, neutral arousal people compared to negative, high arousal people.   It’s entirely possible that when a happy face was compared to a serene face, goats might opt for serenity.  If this was the case, one starts to build an argument that their choice has nothing to do with valence at all (let alone emotion), but rather arousal – lower arousal faces might be favored.

The hope
What CVE and TCE theorists, as well as scientists studying discrete emotions and the dimensions of affect, all have in common is the goal of understanding the mechanisms that generate and subserve emotions. My hope is that remaining clear about the difference between a hypothesis that is about discrete emotions versus a hypothesis that is about the dimensions of affect will speed those discoveries.

 

 

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[i] Thus, there is a dimensional theory of affect.  Valence and arousal aren’t the only dimensions that have been proposed to organize affect, but they are the dimensions that consistently appear in analyses of self-reports of emotion experience and judgements of emotion stimuli.  Jim Russell’s 1980 paper is a classic on this .  Here’s a resource of a broader discussion of affect.  And here’s a recent paper which proposed additional dimensions of affect.

[ii] As far as I know this labeling originated with Lisa Barrett and a version of it (the Classical View) is used throughout her book, How Emotions Are Made.

[iii] For examples of modern articulations of basic emotion theory see: here, here, here, here, and here.

[iv] There are lots of ways that a phenomenon can be modular, for example if the same stimulus or event produces a single emotion, then that Stimulus-Response link is modular.  When framed as a neuroscience argument, modularity has typically been interpreted as their being discrete neural and biological circuity for each emotions – such that emotions have, as Lisa Barrett calls them in here book, “fingerprints” in the brain (as well as voice, face, etc.).

[v] For a historical review of Theories of Constructed Emotion.  For an edited volume on Theories of Constructed Emotion (note that many of the chapters appear to be accessible on the authors’ websites).

We Are Not Born Alone

Tom Hollenstein
Tom Hollenstein

Relationships are good for us. For years, correlational study after correlational study has reported better health and mental health, longer life, less stress and negative emotions, and more happiness and positive emotions for those with good relationships compared to those with poor and/or few relationships.

As an example, consider an upcoming deadline at work that you worry you will not be able to meet, potentially resulting in dire consequences for your company and/or your job. Anxiety. Stress. The better you are able to manage that anxiety, the more likely you are to be able to focus and complete the task. If you are alone, both at home and at work, then the regulation of this stress is all on you. If you have good relationships both at work and at home, there are people to support you, encourage you, and help you feel less anxious.

How does this work?

The prevailing explanation is that relationships add benefits to individuals. Our default, or baseline, is as a solitary individual. This solitary baseline can then be enhanced by close relationships. Have one good relationship? That’s great. Have two? That’s even better. Have great relationships at home, work, and in the community? That’s the best. Let’s call this the Law of Added Positives: psychologically and biologically, good relationships provide extra positives to minimize individuals’ negatives.

However, according to Social Baseline Theory, based on evolution, neuroscience, and emotion advanced by James Coan and colleagues, the Law of Added Positives is not the way things work. In fact, they seem to work in reverse.

For millions of years, humans have been born into environments that included other people. Life begins with strong physical attachments to a mother that become5621007786_aa441a3deb_o strong emotional attachments to her and a group of (often related) others. Those that bonded and worked together for common solutions thrived; those that fought and worked against each other did not. An isolated individual was and remains an anomaly, someone unlikely to have the resources – resources that are as much psychological (e.g., emotional) and biological (e.g., neurological) as material. (e.g., food) – to survive and reproduce.

That is, our baseline or default circumstance is social.

Human biological systems evolved for – and now expect – a social environment where existential risk is distributed (i.e., safety in numbers) and survival efforts are shared. Fight the bear by yourself and you will expend a lot of energy and are less likely to survive; be one of a group fighting off the attacking bear, each individual using less energy with a greater likelihood that you survive. Less energy and greater chance of survival – that is what evolution is all about.

So how does this translate to modern day humans and the relationships-health connection? First consider some preliminary evidence provided by Proffitt and colleagues.

  1. Perception of effort is biased by energy cost/benefit. People perceive hills as steeper and distances as farther away when they are wearing a heavy backpack compared to when they are not. This is taken as evidence that neurobiological systems automatically adjust the perception of difficulty based on the energy required.
  2. Social proximity reduces perception of energy costs. If your friend is standing next to you with a heavy backpack, you will perceive the hill as less steep and the distance as not as far. Just being near someone else lightens the load.
  3. The closer the relationship, the greater the effect. It is not merely the presence of any other human being that indicates load sharing. Your best friend has a bigger effect on your perception of incline and distance than a new acquaintance.

So, if you’re facing that deadline at work alone, it may make the task seem more difficult and less possible.

Coan and colleagues developed Social Baseline Theory based on this and other evidence but tested it more directly, by looking at threat processing in the brain. They conducted a hand-holding fMRI study with three conditions: no hand holding, holding the hand of a stranger, and holding the hand of their partner. Participants received a mild ankle shock on 20% of trials in which they saw a threat cue on a screen. Threat-related brain activity was greatest in the alone condition, less in the stranger condition, and the least in the partner condition. Like the backpack studies, those with the least amount of threat-related brain activity had the highest quality relationships with their hand-holder. Other studies have shown this effect as well.

Instead of relationships adding some extra positives, as the Law of Added Positives would assume, those with the most load sharing were the most efficient at processing threat, requiring the least energy. As social connection and therefore load sharing, diminished, more energy for neural activation was required to deal with the threat. Maybe the law is one of Added Negatives.

Perhaps the greatest implication of Social Baseline Theory is the way that we conduct psychological, especially emotional, research. In an effort to minimize extraneous variables, much of what we have come to understand about human thoughts and feelings and behavior has come from experimental isolation – a single human alone in a room in front of a computer. The assumption has been that the individual is the fundamental unit of analysis and when we include other people it is to enhance or diminish whatever capacities were witnessed in isolation. Perhaps what we have revealed is human functioning at its least efficient, most taxing, and least natural.

Photo credit: https://flic.kr/p/9yH8Mm Shared via a Creative Commons license.

Pride and Guilt: Affective Keys to Sustainability

Lisa Williams

Lisa Williams

By most accounts, the 2015 Paris COP21 Summit in December was a success. Member nations committed to restricting global warming to no more than 2°C, and ideally only 1.5°C, above pre-industrial levels – largely by cutting greenhouse gas emissions. While such nation-level commitment is of utmost import, slowing or curbing the negative effects of climate change will also require people to take actions themselves. A body of recent research highlights how emotions might play a pivotal role in motivating such actions.

Empirical findings point to two specific emotions that might be at the heart of pro-environmental action: pride and guilt. Pride arises from engaging in socially-valued behaviors and reinforces doing them. Guilt, on the other hand, stems from performing socially-sanctioned behaviors and dissuades doing them.

It appears that the simple anticipation of pride or guilt carries the potential to shape pro-environmental behavior. Specifically, anticipated pride from engaging in sustainable behavior and guilt from not doing so promotes intentions to engage in sustainable consumption.1,2 As such, it appears that it would require no more than thinking about the pride one would feel after buying an electric car or the guilt over choosing to not install solar panels to bring about sustainable choices.

There is also promise that pride and guilt can be leveraged to promote sustainability at the group level. In one study, when guilt was elicited by thinking about the in-group’s responsibility for environmental damage, individuals endorsed efforts to redress the damage.3 Pride elicited by thinking about the in-group’s responsibility for environmental protection led individuals to endorse further environmental protection.

We have insight into why pride and guilt have these effects. Once feeling guilty or proud, individuals feel more responsible for their choices,4,5 thus increasing the likelihood that they take it upon themselves to make better choices. More generally, both pride and guilt promote self-control,6 which is key if individuals want to change entrenched past patterns of behavior.

Whether at the individual or group-level, felt in the moment or anticipated in the future, or via responsibility or self-control, it is clear that pride and guilt carry the power to lead us to engage in actions that benefit the environment. If we set personal sustainability targets, pride and guilt will provide the impetus to stick to them.Earth marble

The challenge, then, becomes how to capitalize on pride and guilt to maximize positive environmental behavior. Research in the context of voting behavior suggests that something as simple as the threat of publicizing individuals’ (in)action can be the spark to bring about these socially-oriented emotions, and, in so doing, behavioral change.7 In fact, I’d suggest that pride and guilt may underlie the success of the Neighbourhood Scoreboards Project,8 which investigated the effect of posting energy usage and ranking on the facades of houses in a neighborhood in Sydney, Australia. Simple outcome: a 2.5% drop in energy consumption.

 

References:

1 Onwezen, M. C., Antonides, G., & Bartels, J. (2013). The Norm Activation Model: An exploration of the functions of anticipated pride and guilt in environmental behavior. Journal of Economic Psychology, 39, 141–153.

2 Onwezen, M. C., Bartels, J., & Antonides, G. (2014). The self‐regulatory function of anticipated pride and guilt in a sustainable and healthy consumption context. European Journal of Social Psychology, 44(1), 53–68.

3  Harth, N. S., Leach, C. W., & Kessler, T. (2013). Guilt, anger, and pride about in-group environmental behavior: Different emotions predict distinct intentions. Journal of Environmental Psychology, 34, 18–26.

4 Antonetti, P., & Maklan, S. (2014). Feelings that make a difference: How guilt and pride convince consumers of the effectiveness of sustainable consumption choices. Journal of Business Ethics, 124(1), 117–134.

5 Antonetti, P., & Maklan, S. (2014). Exploring postconsumption guilt and pride in the context of sustainability. Psychology and Marketing, 31(9), 717–735.

6 Hofmann, W., & Fisher, R. R. (2012). How guilt and pride shape subsequent self-control. Social Psychological and Personality Science, 3(6), 682–690.

7 Panagopoulos, C. (2010). Affect, social pressure and prosocial motivation: Field experimental evidence of the mobilizing effects of pride, shame and publicizing voting behavior. Political Behavior, 32, 369–386.

8 Vande Moere, A., Tomitsch, M., Hoinkis, M., Johansen, S., & Trefz, E. (2011). Comparative Feedback in the Street: Exposing Residential Energy Consumption on House Facades. Proceedings of 13th IFIP TC13 Conference on Human-Computer Interaction (INTERACT ’11), Part I, LNCS 6946, Springer: 470-488.

 

Photo credit: https://www.flickr.com/photos/70626035@N00/14327910926 licensed via Creative Commons

Understanding the Early-Life Origins of Extreme Anxiety—Role of the Amgydala

Alex Shackman
Alex Shackman

The internalizing disorders—anxiety and depression—are a major human blight. According to the World Health Organization and National Institute of Mental Health, depression is responsible for more years lost to illness and disability than any other medical condition, including such familiar scourges as diabetes and chronic respiratory disorders. Anxiety disorders are the most common family of psychiatric disorder in the United States and rank sixth as a worldwide cause of disability. These disorders, which commonly co-occur, also impose a substantial and largely hidden burden on the global economy: hundreds of billions of dollars in healthcare costs and lost productivity each year. Unfortunately, existing therapeutic approaches are inconsistently effective or, in the case of many pharmaceutical approaches, are associated with significant side effects. Not surprisingly, the internalizing disorders have become an important priority for clinicians, economists, research funding agencies, and policy makers.

The internalizing disorders generally have their roots in the first three decades of life and there is clear evidence that children with a fearful, shy, or anxious temperament are more likely to suffer from anxiety disorders, major depression, or both as they grow older. As a postdoctoral fellow in Ned Kalin’s lab at the University of Wisconsin and, more recently, as the director of my own lab at the University of Maryland, I’ve used a range of tools and techniques to understand the brain systems that contribute to extreme anxiety early in life. Building on a tradition that dates back to pioneering studies at Wisconsin by Harry Harlow, Karl Pribram, and others, much of the work that I conducted as a postdoc used nonhuman primates to model and understand key features of childhood anxiety. Young rhesus monkeys are useful for deciphering the brain circuits that underlie childhood anxiety. Owing to the relatively recent evolutionary divergence of humans and Old World monkeys (~25 million years ago), the brains of monkeys and humans are biologically similar. Similar brains endow monkeys and children with a common repertoire of social and emotional behaviors, which makes it possible to measure anxiety in monkeys using procedures similar to those used with kids. Another virtue of working with monkeys is the opportunity to collect high-resolution measures of brain activity (using positron emission tomography or PET) while the animals freely respond—hiding in the corner, barking, and so on—to naturalistic threats, such as an unfamiliar human ‘intruder’s’ profile. This would be difficult or impossible to do in children and, somewhat surprisingly, has rarely been attempted in adults (most human imaging studies use fMRI, which requires that the subject remain dead still throughout the scan).

Large-scale brain imaging studies, each including hundreds of young monkeys—in humans terms, roughly equivalent to children and teens—show that anxious individuals respond to signs of potential threat with heightened activity in a number of brain regions. For present purposes, I’ll focus on the contribution of the amygdala, a small, almond-shaped region buried beneath the temporal lobe of the brain (the red regions in the accompanying animation).

Collectively, these studies teach us that amygdala activity systematically differs across individuals. Some individuals show chronically elevated activity; others consistently show much lower levels. Notably, elevated activity is associated with exaggerated reactions to potential danger: Monkeys with higher levels of metabolic activity in the amygdala tend to show higher levels of the stress hormone cortisol and to freeze longer (in an attempt to evade detection) in encounters with the human intruder. Like many other qualities that distinguish one individual from another, work by our group demonstrates that amygdala activity is:

1. Consistent over time and context: We can think of amygdala activity as a trait, like personality or IQ.

2. Heritable: Amygdala activity partially reflects the influence of genes. Parents marked by higher levels of amygdala activity are more likely to have offspring with this trait.

Of course, like any brain imaging study, it’s important to remember that these results do not let us to claim that the amygdala causes anxiety. From this perspective, it is reassuring that mechanistic work in monkeys and rodents demonstrates that it does: selective lesions and other biological manipulations of the amygdala sharply reduce (but do not entirely abolish) anxiety (see for example this very recent rodent study). This is consistent with observations of a handful of human patients with near-complete amygdala damage. For example, one relatively well-known patient (identified as ’SM,’ to protect her identity), has normal intellect, but reports a profound lack of fear and anxiety in response to scary movies, haunted houses, tarantulas, and snakes.

According to Justin Feinstein, Ralph Adolphs, and other researchers who have studied SM over the past two decades,

“She has been held up at knife point and at gun point, she was once physically accosted by a woman twice her size, she was nearly killed in an act of domestic violence, and on more than one occasion she has been explicitly threatened with death…What stands out most is that, in many of these situations, SM’s life was in danger, yet her behavior lacked any sense of desperation or urgency. Police reports…corroborate SM’s recollection of these events and paint a picture of an individual who lives in a poverty-stricken area replete with crime, drugs, and danger…Moreover, it is evident that SM has great difficulty detecting looming threats in her environment and learning to avoid dangerous situations.”

This and other evidence—spanning a range of species, populations, and measurement tools—indicates that anxious individuals’ exaggerated distress in the face of potential danger reflects hyper-reactivity in a brain circuit that includes the amygdala. Systematic differences in amygdala activity and connectivity first emerge early in life and can foretell the future development of anxious and depressive symptoms in humans. These and other observations suggest that enduring differences in amygdala function contribute to key features of childhood temperament, like shyness, and confer increased risk for the development of internalizing disorders, particularly among individuals exposed to stress or trauma. More importantly, this work lays a solid, brain-based foundation for developing better strategies for treating or even preventing these debilitating illnesses.

To learn more about the emotional disorders, please visit the Anxiety & Depression Association of America (ADAA) website, which features a number of useful videos, fact sheets, and other resources for patients, clinicians, and researchers.

Photo credit: The amygdala animation was generated by Life Science Databases, obtained from Wikimedia Commons, and is freely used under a Creative Commons license.

 

The emotional potency of peers during adolescence

Leah Somerville
Leah Somerville

If you had to choose one event that epitomizes your experience as a teenager, what would it be? For me, I immediately think of that moment at the school dance while I was dancing with my middle school crush to November Rain by Guns n Roses. Our slow dancing skills were passable during the first part of the song, but then the tempo picked up … and let’s just say, we were not very smooth at adapting our dancing styles. Although I hope (for your sake) that the same thing didn’t happen to you, I’d bet that whatever memory you do conjure when you think back to your own adolescence is socially and emotionally charged.

It turns out that my adolescent experiences were completely typical of most adolescents—social experiences take on heightened emotional and motivational importance during adolescence as compared to other stages of life. In a study we conducted, we wanted to see how sensitive adolescents were to even the simplest, most innocuous social provocation: being looked at by a peer. During our study, we measured brain activity with functional magnetic resonance imaging in tandem with physiological arousal (measured with the skin conductance response—how much sweat is secreted on the skin during emotional events). We observed that even the simple act of being looked at by a peer was enough to induce heightened emotion reports, physiological responses, and brain activity in adolescents (when compared to adults and younger children). For instance, we saw biased activity in regions of the brain important for representing the emotional value of stimuli and in brain regions involved in thinking about ourselves (to read more, see here). All of these findings add up to the general conclusion that adolescents are highly attuned and reactive to their social environments – even very subtle ones – and that this fact influences a variety of their daily choices and feelings.

IMG_2298

The author of this post at age 13 showing off her spiral perm.

What’s interesting about these findings is that they seem not to be unique to human adolescents. The term ‘adolescence’ is a sociocultural construct that refers only to humans, defined by simultaneous physical and psychological change that ends when an individual takes on adult roles in society (adolescence is most often defined as the approximate ages ~13-17 years). However, some aspects of biological changes during this age range, including hormone changes that define puberty, occur in other mammals as well. Some surprising results have arisen from the study of pubertal-linked changes in social behavior in non-human mammals. Pubertal rats enjoy ‘social play’ (kind of like wrestling) more frequently than adult rodents, and also seek out more novel and potentially thrilling experiences. Perhaps most intriguingly, rodents undergoing puberty also approach potential rewards (in this case, consuming alcoholic beverages) more when in social groups. Whereas adult mice spent the same amount of time consuming alcoholic substances when alone and with peer animals, juvenile animals in the pubertal stage spent more time consuming alcohol when in a cage with familiar peer animals. And it wasn’t just a motivation to consume the tasty cocktail before others got to it – they each had their own sipper.

What lessons can we learn from our furry friends about adolescence and the social potency that characterizes this age range? It is often assumed that peers take on heightened importance in adolescence due to overt concern about social status. However, it seems unlikely that such complicated, strategic motivations would drive rodents to behave differently around peers. This raises a second possibility, that there are “undercover” or non-deliberate ways that adolescents are influenced by social contexts. We believe that adolescents’ brains are biased to assign importance to social information, which imbues social settings with an extra boost in power to shape their feelings, motivations, and decisions. Although more research needs to be done to address questions like “why” and “how”, I guess that’s why I’m still mildly embarrassed by my tragic bout of dancing (and simultaneously thankful I grew up before the days of smartphone cameras).