Research and Advanced Education
Social Cognition and the Laboratory run by Diana Prata
The way we behave and the way we feel things, the ties we build with others, or the coldness with which we move about in society, are all features of a single species: the human species. This is the very species that is able to stand for the best causes and create the most magnificent works of art, while being capable of decimating parts of its own existence. Experiencing fear, euphoria, pleasure, or not feeling anything at all, are all emotions lodged in the same origin. We often say we have a feeling about others, as we react differently according to the empathy or suspicion that is aroused in us. None of this is supernatural or magical, but all chemical and due to the sum of 86 billion neurons that shape the human body's most mysterious organ: the brain.
Weighing a little over a kilo and fitting in the palm of your hand, its texture is that of a sponge with gelatine. When we are awake, the energy the brain generates is equivalent to that of a 20-watt light bulb while using up around 20% of the overall calories we burn daily. The brain tissue does not feel pain because it does not comprise such receptors; rather, it merely activates other structures in the body to feel pain. If we were to travel inside the brain, we would find that the neurons communicate with one another because they have synapses connecting them, totalling 10 trillion in all. Geographically divided into 7 different areas (brainstem, cerebellum, occipital lobe, parietal lobe, frontal lobe, temporal lobe, hippocampus and amygdala), today there are areas that arouse greater interest; we know, for example, that the hippocampus can grow according to the learning we foster in ourselves. Today, we also know that, in the hippocampus, we can create new neurons and synapses over the course of our lives. Age does not destroy everything, as there are capabilities in our brain that improve over time, such as the wealth of our vocabulary, or the ability to manage conflicts and emotions.
But where do the explanations to all these chemical manifestations in the brain come from?
Since the dawn of time, even in primary animals such as earthworms and insects, some neurons formed a reward system that enabled them to survive. Rewarding experiences were coded as releases of dopamine. Throughout evolution, there emerged species that felt the need to live in groups for protection, predation, creating offspring, etc.; the response to such a need appeared in the form of oxytocin.
Diana Prata, a neurobiologist, researcher and Group Leader at the iMM, heads her own laboratory comprising a team of 10 people, while studying that chemical formula in the human and animal brain.
Diana, please tell us about oxytocin and what your study focuses on.
My study is focused on understanding how oxytocin works with the dopamine system, as the latter, in turn, is strongly associated with reward. When animals started getting into groups, oxytocin started to play a role in social cognition. Of course, at that time, the dopamine and reward system already existed, and so, since nature always “uses” what already exists in order to “invent” a new function, we believe that oxytocin will use the reward system to “tell” the animal that a good social interaction with someone is socially rewarding (for instance, receiving a smile or help). Thus, we will learn who those that help us are and where to find them, thereby creating affiliation. Whereas dopamine shows reward in sweet things, in warmth, in satiety, we feel that oxytocin, while interacting with dopamine, will code rewards in the social dimension.
Oxytocin can be quantified in the blood or in saliva, as well as in the cerebrospinal fluid via a lumbar puncture; however, this is highly invasive. To understand the molecule's actions in the brain, what we do is, we base ourselves on the momentary manipulation of the levels of oxytocin, for the time being in males only, as there is less fluctuation in the level of this hormone over the course of a month, and we then observe their behaviours and brain activation. It is the correlation between that administration, the behaviour and the observation of the different brain activation, particularly in the area of the amygdala and the striatum (non-circuit centre of reward), which have characterised the role of oxytocin in social cognition.
And what happens when oxytocin is administered?
At the moment, the effect of the administered dose, which is half of what is given to women who are unable to breastfeed, lasts from thirty minutes to one hour, causing cognitive changes. It has been shown that intranasal oxytocin prompts greater cooperation, in more quickly resolving a couple's discussion and with more constructive words, and a better identification of the emotions of others based on vision. But for now, these are initial studies still calling for replication to be substantiated, and which do not provide absolute guarantees.
We are now starting to realise that oxytocin has psychological effects, one of which, quite proven, is that it is relaxing. Oxytocin is released by our brain when we touch or are touched, or massaged, when we hug or when we look people in the eye, or in social situations, for example, when a mother is taking care of her baby, and, indeed, all these situations are relaxing. There are those who maintain that oxytocin is also released in order to provide relaxation in situations of stress, both to oneself and to other people, and facilitates approaching others. For example, if a person is experiencing stress, or fear, the release of oxytocin in his/her brain will help bring them closer to someone, to a group of friends, for potential help. In turn, the other person will also feel less repulsiveness and greater motivation for being approached, even if it is someone in a stressful situation, when oxytocin levels are higher. Supporting this idea that oxytocin reduces fear, there is the well-established discovery that inhaling oxytocin reduces the activation of the brain's amygdala (which typically codes fear and repulsiveness), when in the presence of a frightened face. It is thought that this is how oxytocin enables closeness and, therefore, affiliation, especially facilitating mutual assistance between individuals of the same social group, and, in the most extreme and critical case for survival (and genetic replication), between mother and child.
So can we say that oxytocin plays a social role?
We are taking the first steps to try to understand this social role, namely how oxytocin regulates the behaviour of social closeness. Here, we have two aspects: one involves closeness with a new person, leading to affiliation with that person, if such closeness is rewarding (as I've mentioned, we believe such learning depends on the dopamine system). As we have also seen, closeness is important for help; for instance, a mother who has seen her baby showing fear is not supposed to flee, but to calm and soothe; moments of mother-baby contact are clearly accompanied by a greater release of oxytocin, in order to, it is thought, counteract contagion by fear and repulsiveness. Afterwards, with the continued positive interactions facilitated by oxytocin and dopamine together, we believe a growing affiliation is further strengthened. However, there is a second aspect involved in the action of oxytocin, the “other side of the coin.” While, when a person is part of our group (and typically no group is more cohesive than a mother and her child), oxytocin causes effects of closeness, it is also true that oxytocin can entail more “aggression” towards people from external groups, in situations of competition or scarcity of resources. Getting back to the mother-child relationship, such “enhanced” defensive behaviour makes sense for protecting the child. Supporting this idea are laboratory studies involving neuro-economic games in which adults choose to compete or cooperate. In these, the administration of intranasal oxytocin has been shown to enhance competition (more than usual) with members of an external group, versus those in the same group. That is, the effect of a greater release of oxytocin in the brain on the closeness-related behaviour depends on the social context, when faced with an individual that threatens us or who needs our help.
Fear, then, is also a very underlying idea. If we often train the brain to fear-related situations, does it learn to react differently?
Fear activates an instinctive response from our sympathetic autonomic nervous system, which is: fight, flight or freeze, where, in a dangerous situation, the animal chooses one of these 3 strategies for its survival. This will depend on the type of aggression and on the type of animal. What we call instinct is such an automatic response from the brain that we do not assume it as a conscious action. However, the brain is plastic up to a certain point, and the fears of flying, spiders or speaking in public, for instance, can be treated. Using cognitive-behavioural therapy, for example, psychologists try to get people to understand what type of thoughts are behind their fear, and then, equip them with strategies for reinterpreting those situations. The behavioural therapy of exposure is focused on de-sensitisation: the person is gradually exposed closer to the stimulus that induces fear, and, upon learning, through positive reinforcement, that there is no danger, over time his/her brain will no longer associate the stimulus with a threat, while no longer inducing a physiology typical of fear (the aforementioned "fight, flight or freeze")
Seeing a face that is showing fear can also elicit fear in the other person, through emotional contagion. We've already seen that this fear was reflected in an activation of the brain amygdala, and that it was reduced through increased oxytocin levels in the brain.
A observação de uma cara com medo pode, também, suscitar medo na outra pessoa, por contágio emocional. Já vimos que este medo se refletia numa ativação da amígdala cerebral, e que era reduzido pelo aumento dos níveis de oxitocina no cérebro.
And when we show empathy toward someone, that is not supernatural, but oxytocin working…
Empathy has been shown to be modulated by oxytocin. There are 2 types of empathy: the cognitive type, the one I study, the one a person uses when attempting to uncover what the other is thinking, feeling or intending to do. And then there is emotional or affective empathy, which is that of contagion: for instance, crying being triggered by seeing someone else crying.
Regarding the former type of empathy, there is a very well-known test where we have to guess what is behind 36 photos of eye expressions: for example, envy, panic, satisfaction, etc. In a study with a placebo, oxytocin was given to people one day, and not the next day. When the test was conducted under the effect of the oxytocin, their identification of emotions improved significantly. This makes sense because, with regard to closeness to or affiliation with someone, it is crucial to understand the intention, thoughts and emotions of others. We need to know, to infer, whether or not that person is trustworthy, for both protection's sake and for helping others. Oxytocin is thought to play a role in cognitive empathy, which is an important cognitive process in behaviours of closeness and affiliation.
When envisioning the study of oxytocin for treating neuronal diseases, what does this tell us?
For instance, with schizophrenia, the initial idea was to treat more particular symptoms, as the focus was always to relieve psychoses and delusions caused by the disease, but that approach neglected to integrate schizophrenics into society, before and after the condition. Social training as a form of therapy, possibly using oxytocin as a spray, to improve the relationship with others and confidence, has yet to be implemented. The same goes for depression, bipolar disorder, drug addiction, or Alzheimer's disease. And in all of these, the part of the social dimension is, in fact, still being neglected. I believe oxytocin as a nasal spray and used as a continuous treatment, over a certain period of time, can be beneficial.
If we validate the behaviour-oxytocin-symptoms relation, then we can also use a spray-free therapy, that is, only through behaviours, for example: hugs, dancing, massages, games between people and other social activities. This is because we would have a biological validation that these behaviours stimulate the oxytocin system and that this, in turn, when remedied in patients, improves behavioural symptoms. And we don't have to think of these techniques merely as treatment, as they, too, can help with the prevention, for instance, of social isolation, which increases stress conducive to schizophrenia, for example, while reducing activity in the elderly, which, in turn, is conducive to dementia. Periods of chronic stress inherent to migration, urbanism, and traumatic events, are believed to stimulate schizophrenia, though the person's genetic background has a major influence.
People suffering from a disorder, who look less at others, undergo changes to the oxytocin adjustment system, in genetic terms. This is consistent with the idea that oxytocin is crucial to empathy, closeness and affiliation. What's more, there are clinical tests showing an improvement in the symptoms of autism when administering intranasal oxytocin, such as an increase in the period of time autistic people can look other people in the eye, along with a greater understanding of the feelings and intentions of others (cognitive empathy). In autistic children, this has been noticed in recent clinical tests, although the ideal dosage and duration are yet to be determined.
In short, in terms of treatments involving the manipulation of the oxytocin system, we still have many open possibilities, including some recent ones that are very promising, as is the case with autism. We need to keep on testing, replicating and consolidating, so as to arrive at safe and effective solutions.