Humans aren’t the only lonely species. Monkeys may be lonely too.

Eliza Bliss-Moreau

More than two decades of research demonstrates that people who have more social connections do better—in terms of their general health, ability to recover from illness, and longevity (for a classic, oft cited study, see here; for a review, here; for popular press coverage and a lovely long read on human loneliness, here). Perhaps unsurprisingly, it’s not just the number of people you’re connected to that matters for your well-being. Whether people’s social relationships meet their social needs also has critical importance for health outcomes  regardless of how many social connections they have (for reviews of this literature see here, here, and here). That is, it’s possible to be well-connected socially and still feel totally alone in the world. It is also possible to have very few social relationships but not feel lonely at all.

Exciting new evidence illustrates that we humans might not be the only ones to experience loneliness—rhesus macaque monkeys may as well. As part of an interdisciplinary team, Dr. John Capitanio examined the social behavior of adult male macaques at the California National Primate Research Center and identified three different patterns. Some monkeys engaged in a lot of social interactions with other males, adult females, and younger monkeys. Other monkeys did not engage in a lot of social interactions at all. What’s critical some of these “lowly social” monkeys seemed fairly content with their lot in life—they went about their daily business without trying to build new relationships.

Housing&Enrichment©K.West-CNPRC,039The other lowly social monkeys did seem to care about their lot in life, however. They often physically approached adult females and younger animals, presumably in an effort to initiate an interaction. Similarly, the monkeys would walk by those animals to see what they were doing, even when trying not to engage with them. The fact that these behaviors were observed with adult females and younger monkeys suggests that these “lonely” adult male monkeys may have been looking for easy social relationships (because of how macaque societies are structured, relationships between adult males can be challenging). This heightened social interest persisted when evaluated 1.5 years later. In other words, there were monkeys who appeared to chronically desire social relationships but did not manage to make them happen—a potential monkey homologue of human loneliness. What’s more, as Capitanio points out, these lonely monkeys may be better models for human loneliness than previous animal models because the phenomenon emerged spontaneously in the context of large naturalistic social groups, rather than as a result of experimentally separating animals.

In and of itself, the finding that nonhuman animals might have the capacity to be lonely is an interesting one. It suggests that experiencing a mismatch between one’s social realities and one’s social desires is evolutionarily old, raising questions about what function loneliness might have served for our ancestors.

But perhaps more importantly, animal models of human psychological phenomena, such as a monkey model of loneliness, are critical to understanding the biological processes that contribute to them. Nonhuman primate (e.g., monkey) models are particularly important for understanding human function and dysfunction because we share so many biological and social features. Monkey models allow for precise experimental control (e.g., the ability to manipulate social environment, diet, sleep-cycles, etc.), intensive long-term longitudinal studies (i.e., the ability to track and evaluate many individual animals over the course of their entire lives), and the development of causal biological models. Understanding biological mechanisms is critical for developing effective early interventions and treatments for deleterious psychological experiences. Studying lonely monkeys may therefore unearth the biological and social processes that can be harnessed to help lonely humans in the future.

Photo: Adult male rhesus monkey at the CNPRC eating a zucchini. Photo Credit: Kathy West, CNPRC.

Early Explorations of the Final Frontier: The Human Brain

Eliza Bliss-Moreau

Yesterday, that National Institutes of Health (NIH) announced the awarding of $46 million as part of the new BRAIN Initiative (Brain Research through Advancing Innovative Neurotechnologies).  The BRAIN Initiative is a multi-agency funding program aimed at developing the technologies necessary to map the functions of the brain. We’ve learned a lot about the brain over the last century, but there’s so much more to learn that many neuroscientists consider the brain “the final frontier”.  Dr. Francis Collins, Director of the NIH, has likened the BRAIN Initiative to President Kennedy’s race to the moon. In a world of discovery where we use methods like optogenetics, positron emission topography, magnetic resonance imaging, DREADDs (designer receptors exclusively activated by designer drugs), electrocorticography (which we’ll discuss in future posts) to understand how areas and circuits of the brain work and how they contribute to emotion, it’s easy to forget how far the neuroscience of emotion has come in the last half-century or so.  And, of course, it’s also easy to forget how far we have to go.

The goal of today’s post is to take a *very* brief walk back down memory lane to remember whence we’ve come (circa early 20th century) and the lessons from the pioneers of the neuroscience of emotion that we should carry with us as we continue to explore the brain.

Before we could look into the human brain using neuroimaging, our knowledge of how the human brain functioned was largely made possible by people with diseases or injury. In some cases, people got tumors that required surgery.  When the tumor was removed, a given brain area was disturbed.  Changes in the person’s behavior following surgery were therefore logically linked to the damage. Sometimes people had strokes or aneurysms that damaged the brain.  Sometimes people had injuries that damaged the brain (e.g., Phineas Gage).  In yet other cases, surgery was performed on the brain to alleviate epilepsy or psychological illness. One important point to keep in mind is that regardless of the cause of damage, studies of these sorts were not studies of the healthy, normal human brain; they were studies of the diseased or injured brain.  It wasn’t until different sorts of neuroimaging or recording techniques arrived on the scene as methodological tools that we were able to evaluate the healthy human brain.

Damage that occurred because of a tumor, a stroke, or injury most often crossed multiple anatomical areas somewhat randomly.  This made it challenging to conclude which psychological functions were generated by which brain areas. But damage that occurred to alleviate illness was typically targeted, or what neuroscientists call “focal”. Studying people with this sort of damage allowed the pioneers of emotion neuroscience some of the first glimpses into the role of particular brain areas in the generation of emotions. By combining observations from the clinic with animal studies in which comparable brain damage was made or in which regions of the brain were electrically stimulated (which will be discussed in a future post), the neuroscience of emotion was propelled forward.

These early emotion neuroscientists—men like Cannon, Papez, and MacLean—used what their fairly rudimentary tools (by modern standards) to reveal some truths about emotion that still ring true today:

Emotions don’t live in particular areas of the brain but rather came to be via distributed circuitry throughout the whole brain. The expression, experience, and perception of emotion are made possible by slightly different circuitry.  Emotion comes to be in part via the activity in the peripheral nervous system—that is, we “feel” emotions in our bodies.  Certain brain areas are “hubs” of activities—central areas much like bus terminals in a big city where lots of signals arrive and are subsequently transmitted to other areas for further processing.

For examples classic early papers see here, here, here, and here.

Over the years, these important messages that stand the test of time (and modern methods) were often lost in attempts to localize particular emotions to particular neural regions.  [The most pervasive of the localization hypotheses is that the amygdala is the locus of fear.  The hypothesis is so pervasive and the evidence to support it so lacking, that we’ll take on that idea in another full post.] Localization attempts focused on mapping discrete emotions to discrete neural structures, often relying on poor operationalization of emotion related variables.

An early scientist might label a phenomena “rage” without ever defining what rage actually was (By answering questions like: are we talking about the perception of rage? The expression of rage? The experience of rage? How do we tell the difference between rage and anger? If this phenomena is being observed in animals how do we know that it maps on to the human experience of rage?) or indicating a specific way to measure it. Another important, often overlooked point is that changes to emotion observed in these human patients were typically described in diffuse, nonspecific terms—for example a patient’s psychiatry symptoms might have “improved” following surgery.  Improvement in anxiety or depression symptomology, for example, were taken as evidence that particular brain areas removed during psychosurgery were involved in emotion.  Advancement of emotion neuroscience requires carefully defining emotion terms and characterizing emotion phenomena in ways that can be systematically measured.

Despite these caveats, the lessons from early studies of the emotional brain are powerful and not to be ignored as we enter an era of the BRAIN Initiative—careful experimentation and measurement can yield impressive gains in knowledge, even with fairly rudimentary tools.

 Photo credit:

Introduction to the Neuroscience of Emotion Series

Eliza Bliss-Moreau

In the coming months, we will be posting a number of stories on the neurobiology of emotion. Understanding how the brain creates emotion has important consequences for everything from whom we charge with crimes (are crimes that occur due to a brain disorder that changes emotions different from those that are not?) to how we treat depression (is using chemicals that effect the brain a better option than talk therapy?) to the ethics associated with meat production (if pigs have brains capable of emotions, does that change how we treat them as we turn them into meat?).

As neuroscientists in the 21st century, we are equipped with powerful tools to ask questions about emotion. Modern neuroscience techniques are comparable to the methods detailed in science fiction decades ago—we can “see” into the brain of a normal person while they are in a MRI scanner experiencing emotions; we can turn on and off areas of animal brains with a beam of light; we can record activity of single cells in the brain of animals and nerves throughout the body.  The experiments that use these tools and the data that are produced by these tools are complex and often indirect measures of brain function and the emotion produced by brain activity.  Their portrayal in the modern media often does not do justice to their complexity.

Over a series of posts, we’ll explain how different neuroscience methods actually work, how they are used to study emotion, and what the take home messages are about how the brain creates emotions.  We hope to paint a picture of how exciting and challenging research on the brain basis of emotion is, how powerful our existing tools are, and how much we still have to learn.

Neuroscience stories about emotion make the national and international news frequently these days (like this, this, and this, for example). With the abundance of these stories, it’s easy to forget that it wasn’t that long ago that we had very limited tools to study the brain in a living, breathing person or nonhuman animal. [In later posts, we’ll talk about what we’ve learned about emotion from brains that are not in living beings.] Prior to the advent of neuroimaging technology which lets us measure activity in the brain (either electrical activity, blood flow, or the movement of chemicals), most studies of human emotion occurred when people incurred brain damage.

Perhaps the most famous case of accidental brain damage interfering with emotion, is the case of Phineas Gage. Phineas Gage was a railroad worker born in the 1820s.  In 1848, he was working to build a railroad in Vermont when a terrible accident occurred.   He was using a long metal rod and blasting powder to blast rock away at the site.  During one of the blasts, he lost control of the rod and it flew through his head.   The metal rod entered his skull under his left eye and exited out of the top of his head, damaging a large area of frontal cortex in the process (see).  Surprisingly, Gage lived.  But he was never the same again.  Prior to the accident, he was a responsible, upstanding guy.  After the accident he was said to be vulgar, unable to control his behavior, and generally intolerable.  [Although, there’s a fair amount of debate about the extent to which his behavior actually changed on account of poor records, see].  Modern studies of the brain areas damaged in Gage’s case suggest that those areas contribute to the regulation of emotions.

Gage’s case was just one of many that point to a link between particular areas of the brain and the generation and regulation of emotions.  The next post in this series will address what we’ve learned about emotion from other instances in which humans acquire brain damage.  Sometimes damage is created intentionally—typically to treat intractable diseases (like seizure disorders).  Sometimes damage occurs during strokes.  Finally, there are some diseases out there that target specific brain areas and render them nonfunctional.

In addition to exploring what the emotional lives of people with brain damage have taught us about the neuroscience of emotion, we’ll also be answering questions like: How does neuroimaging really work?  What have animal studies of the brain and emotion taught us? What are the biggest and most dramatic misconceptions about the neuroscience of emotion? How do different brain areas work together to create emotions?

If there are other specific topics you would like to see covered, please email one of the founders or leave a comment for us below.

Fido feels?

Eliza Bliss-Moreau

The emotional lives of dogs has become a hot topic as of late and made some big splashes in the media. In a recently published study, Christine Harris and Caroline Prouvost claim that dogs, like humans, experience jealousy.

The researchers tested pet dogs and their owners while their owners interacted with three different objects:  a toy dog that moved and made noise, a jack-o-lantern figure, and a children’s book that made noise.  Owners were instructed to interact with the objects and ignore their dogs.  When owners were interacting with the toy dog (compared to the other objects), their pets were more likely to touch them or the objects, move between the owner and object, and look more at the owner and object.  Dogs also “snapped” more at the animated toy dog than the other objects.  The authors state that these behaviors are “indicative of” jealously.

The report makes three fairly substantial, critical assumptions—two about the nature of emotion and one about how dogs behave with toys.

3210109272_df9c66d773_oThe first assumption is that behaviors map on to emotions in a specific way.  The idea here is that we can know the internal state of an individual based on his or her behavior.  In other words, if behavior X occurs, then emotion Y is present.  This is an intuitive idea that resonates with people.  But, the scientific evidence suggests this is not true. The problem is that there is a substantial amount of evidence that suggests this is not the case, even in humans who can tell us how they feel while they are behaving.  Overt behaviors don’t relate in specific ways to specific emotions.  Physiological patterns (e.g., what your heart is doing during an emotion) don’t relate in specific ways to specific emotions.  And so on.  Sometimes people (and rodents and dogs and monkeys) fight when they’re fearful and sometimes they run away.  Sometimes people smile when they’re happy, sometimes they make no facial behaviors at all, and sometimes people smile when they’re angry.   So particular behaviors aren’t “indicative of” particular emotions.

The second, related, assumption is that behaviors in animals are indicative of emotional states that are human-like.  This logical leap has been made for decades (particularly in studies of fear).  A freezing rat is said to be a fearful rat.  In actually, we have no way of knowing (yet) whether a freezing rat is experiencing human like fear at all.  Freezing is a fairly simple neurobiological reflex.  It’s hard to equate it with human experiences of emotion. Like for example, the experience you might have when you hear that a plane has crashed and your lover was on it, or the feeling you might have when you’re walking down a dark alley and hear heavy footsteps behind you.  Making the assumption that rat freezing is the same as one of those human experiences is a fairly large (and as I and others argue, problematic) logical leap.

The third assumption is that dogs’ behaviors differed with the toy dog because of emotion and not some other psychological state.  But there are a number of other possibilities.  For example, it’s possible that dogs were simply more interested in the toy dog because it was more complex or interesting or because it looked like a dog.  It’s possible that the dogs wished to play with it themselves, or were confused because it emulated a dog without being one.  Since the dogs were never tested with the objects and without the owner, or when the owner was not paying attention to the toy, none of these hypotheses can be excluded.

So, can Fido feel jealous? Possibly.  Humans have selectively breed dogs over thousands of years, creating modern day dog that is particularly responsive to human emotions, gestures, and eye-gaze.  Some of these capacities are unmatched even in our closest genetic relatives—the nonhuman primates.  Dogs also have fairly complex brains that may be capable of the computations needed for a complex socially oriented emotion like jealously.

But, based on this single study alone, the jealously jury is definitely still out.

Informed Consent and Debriefing Matters

(especially for emotion science)

Eliza Bliss-Moreau

I always thought that our first set of posts on Emotion News would be focused on the history of emotion science or a discussion about why the science of emotion matters for Regular Joe or Jane’s daily life. While attending a recent meeting, Kristen and I discussed the “Facebook-“Emotion-Manipulation” Debacle” that was still surging on the internet after more than a week in the news, though, and realized that we had different views about its importance for Emotion Science. So, we figured that we’d make our inaugural blog posts about it, hopefully setting the tone for our blog: emotion science matters for everyone; we don’t always agree on the how or why; and it’s important to have a forum to discuss these issues.

Many of the issues with the study on “emotion contagion” done by Facebook have been reviewed in detail elsewhere. In brief, they range from concerns that the conclusions about emotion spreading via social media are over blown to concerns that the manipulation of emotional information on people’s Facebook feeds was unethical. It would take pages to detail them all, so I’ve decided to focus on one aspect of the ethical complaint: were participants in the Facebook study properly informed of the experiment?

Facebook, and others, have argued that agreeing to their data use policy constitutes “informed consent”. Informed consent is the permission that scientists get from people to conduct and experiment with (or on) them (or the permission that clinicians get to provide medical treatment in a hospital or clinic setting). Rules vary a bit from institution-to-insitution and nation-to-nation but in general, informed consent procedures typically give people an idea of what they’re getting into—a general overview of the experimental study or procedure, some information about its purpose, and almost always the explicit option to end participation at any time without any consequence. Informed consent information is required to be clearly written and in common language. In cases where there might be concern about potential participants’ understanding the consent information, scientists are typically required to discuss all of the information with them.

To be clear, informed consent is not associated with all data. The panels of people that review the ethical implications of studies, called Institutional Review Boards, sometimes wave the requirement for informed consent when the impacts of the study are deemed to be minimal, where sensitive data will not be collected, or where the procedures are deemed to be comparable to things that people would normally do on a day-to-day basis, among other reasons. Further, as people in the digital age, we generate a lot of data—we click around on the internet, information about our salaries and demographics is recorded by the government, even information about our health ends up in digital archives. Scientists can typically use these data troves to test their hypotheses. Access to data sources is typically granted via an institution (either the college or university or agency at which the scientists works or the one that holds the data), but as an individual who has generated data points, you may never be informed about a specific hypothesis test being done on “your” data. The question is whether the Facebook study fits into any of these categories of research. Some argue yes, some argue no.

Informed consent is almost always required in cases where scientists are substantially manipulating some aspect of human experience. And that is what Facebook claims to have done (although the jury is out about whether or not their claims represent a substantial manipulation of experience). Given that, it is not clear that the data usage policy is sufficient to be an actual informed consent.

Users of Facebook agree to a data usage policy which basically says that Facebook can use the data you generate (posts, likes, comments, and so on) as they wish. Many users agreed to the data usage policy well before the actual experiment and it’s likely that many did not read it completely. While the latter issue is the problem of individuals, there is growing concern that many usage policies (called End User License Agreements or EULAs) are actually too long to read—like you would have to spend, literally, months reading them. If companies are creating EULAs that are literally too long to read knowing that people are not reading them, do they count as informed consent? Further, because data usage agreements may have been completed long before the experiment, we didn’t know when the experiment would take place and therefore had no ability to opt out (which could have been as easy as not opening Facebook during the experiment).

While we typically focus on the informed consent procedures that happen before people complete experiments, how people are informed about the experiments after their data has been collected also counts. In emotion science, it is sometimes, even often, the case that we don’t tell the whole truth and nothing but the truth during informed consent procedures. We might tell you that you’ll be listening to music and then complete a few questionnaires about who you are when we are actually using the music to induce a positive or negative mood and measuring whether your mood changes with the questions. We might even tell you a completely made up story about what you’re doing and why (called a “cover story”). These procedures are used because what you know about a study can actually bias how you respond. But, at the end of the study, we come clean in what is called a “debriefing”. We give you more information about the study and why you completed the procedures that you did and even why a cover story was required. Some debriefings also give participants an option to have their data removed from the archive once they know the true purpose of the study. Publishing a paper full of findings, like Facebook did, does not constitute a debriefing.

The primary success of the Facebook study may be that it has gotten scientists and the public talking about these issues. Since the dawn of the internet, we’ve been creating a lot of data. As the cost of storing that data falls, collection of and long term archiving of that data becomes possible. It’s time to think seriously about how we inform people about how their data is being used and what sorts of ethical principles will guide the design of large internet studies in the future. Especially, if we plan to manipulate emotions.