The Altruistic Brain

How we are Naturally Good

Darwin had already openly proposed that the more cooperative groups would be better equipped to beat the less cooperative ones and that this fact could favour the survival over time of the former. However, compassion, altruism, cooperation and, in general, any prosocial behaviour has been considered an evolutionary puzzle.

A compassionate or altruistic act consists of giving up some of one's own fitness to another individual, and therefore individuals who perform such acts would, in theory, be at an evolutionary disadvantage compared to those who do not.

Over the last few decades, however, mechanisms have been proposed to overcome this 'pitfall', although each of these mechanisms has its limitations. The mechanisms that have received the most attention and credit –though not without disagreement among evolutionary biologists– have been the following: (1) Hamilton's rule, which contains the idea of inclusive fitness or kin selection; (2) reciprocal altruism; (3) indirect altruism; and (4) cultural group selection.

What is interesting about the proposed mechanisms is that, being compatible with each other and varying in relative importance depending on the circumstances (cultural, temporal, environmental and others), they all converge in the sense of favouring prosocial behaviours, so it is logical to think that there must be universal brain mechanisms that favour them.

In the human species, the origin of altruism can be linked to the needs derived from the upbringing of offspring. Women are, among hominids, the most fertile. Under the conditions in which hunter-gatherer groups live, they can produce a young approximately every three years. As Sarah Blaffer Hrdy says in 'Mothers and others', human females, which are the apes that produce the largest, slowest maturing and most expensive babies, are also the ones that reproduce the fastest. Such reproductive rarity is only possible if other members of the group, such as the breeding mate, grandmothers and sisters, but also other people not so directly related to the mother, cooperate in the breeding.

But cooperative parenting could not succeed if the help received by the mother, at least from those outside the family, is not reciprocated or is not expected to be reciprocated. Therefore, the other necessary ingredient is that of reciprocity, which I have mentioned earlier. And once this path begins, direct reciprocity would be followed by indirect reciprocity.

In this context, it is perfectly understandable that the most attractive individuals, the most highly valued by others, would be precisely the kindest, the most cooperative, and in this way these behaviours would have been selected in the groups of our ancestors, certainly of our genus but perhaps also of their Australopithecus ancestors. After all, prosocial behaviours are not the prerogative of humans, although it is true that we are the primates in which such behaviours are most highly developed.

The greatest difficulty, however, lies in explaining pro-social behaviour towards individuals belonging to cultures and peoples with whom we have no relationship. Both sources of ethical behaviour –deontological and consequentialist– ultimately refer to the consideration of all human beings as having the same status and nature and therefore deserving the same treatment.

But the biological, cultural or biocultural mechanisms that explain the selection and survival over time of apparently maladaptive behaviours are one thing, and identifying the neurological bases of these behaviours is quite another, although related. The book I am discussing in this review addresses precisely these aspects, and does so by formulating what the author, Donald W. Pfaff, calls Altruistic Brain Theory (ABT). What follows is a summary of the author's proposals, followed by my personal assessment of his ideas.

Neuroscience starts from the premise that all our social behaviours are products of the mind and that the brain is the organ that produces it.

The human brain is programmed to care for others. Many of our impulses, reactions and abilities are more a product of our nature than of nurture. The innate biology of the brain drives us to be good people. We are wired, according to Pfaff, to behave altruistically.

According to ABT, the human brain processes altruism in five steps:

1. The Central Nervous System mentally reproduces the act that the subject is going to perform towards another person. There is nothing special about this step, as it is characteristic of any process in which actions are planned or an attempt is made to foresee the consequences of something that is going to happen or may happen.

2. The subject imagines the person who will be the target of his or her act. This step is necessary for the subsequent evaluation of the act. In many cases, there is no such person in particular, as the altruistic act is directed at people who are not known. In this case, the person imagined (or visualised) is a generic one.

3. The image of that person is blurred with the image of oneself. When nerve cells are activated and send signals to the face of the other person (real or generic), they excite the neurons whose activity represents the self-image. This process is called "cross-excitation". This step is crucial, as it provides the basis for treating the other person as oneself.

4. Once the act is represented in the brain and the combined image of the other and the self has been formed, neurons in the prefrontal cortex assign a positive or negative value to the act. The valuation of the act involves brain regions that regulate different forms of emotionally significant behaviour. Certain areas of the prefrontal cortex and the amygdala are some of those brain enclaves.

5. The subject decides whether to act or not. According to step 4, if the consequences of the act are positive, he/she acts; if they are not, he/she does not. Neurons in the insula, a poorly known region of the brain, seem to be involved in this step. These neurons respond to states of pleasantness (leading to performance of the prosocial act) or moral unpleasantness (leading to inaction), and are connected to motor control systems in the forebrain involved in the evaluation of the consequences of acts.

Each of the described steps occurs below the level of consciousness and is completed in a tiny fraction of a second. The author describes in detail the neurological processes involved in each of the above steps, and puts them in real-life contexts, using well-known cases of altruism or prosocial behaviour, even to extreme degrees.

According to the author, the neurological processes of prosocial acts are evolutionarily related to those involved in our reproductive instincts towards sex and parental care. In other words, friendly behaviours that evolved to promote reproduction provided the neural substrate that enabled altruistic behaviours beyond the boundaries of the immediate family. Sex and parenthood would have been "the laboratory in which our species learned how to spontaneously give or help, simply because that act was necessary to maintain parent-child relationships, and to keep their helpless infants alive”.

Altruistic acts produce a deep pleasure in the continuum that comes from sexuality. Connection with others is essential to our well-being. We are best in the company of people we know are willing to help us, and we know that they are willing to help us if we are willing to help them.

The community to which we belong is as old as humankind, for we are comforted by the sense of connection and security it provides. Nature designed us to love one another because we are more likely to survive communally.

The author links neuroscientific evidence to the existence of universal ethical principles, such as the Golden Rule, common to virtually all religious faiths and moral philosophies. In this way, he attempts to formulate an ethical universal, which he links to the existence of the aforementioned neurological processes in a cursory manner.

What has been said up to this point is intended to summarize the first part of the book. In the second part, the author sets out how his theory could be used to improve our moral behaviour by removing the obstacles to good behaviour. I found this second part of the book excessively speculative and, perhaps for that reason, of much less interest than the first part. Therefore, I will omit a description of its contents.

The book, however, is not without interest, as it provides valuable information about neurological processes involved in prosocial behaviour, together with a wealth of complementary information. Its main weakness, in my opinion, is that it is not convincing in its assertion of a supposed universal goodness of human beings, a fact that would be supported by the existence of the above-mentioned processes.

The truth is that the neuronal wiring that the author invokes, although it is indeed part of our brain endowment, does not exclude the fact that there are antisocial behaviours and that, on too many occasions, these have very negative effects, completely cancelling out the consequences of prosocial ones. Pfaff argues that when behaviour moves away from this essential goodness, there are two possible reasons for this.

One is that the conditions of deprivation and abuse in the early stages of many people's lives are responsible, through their effects on the central nervous system, for antisocial behaviour. Therefore, he believes that if these conditions were eliminated, it would also lead to the development of kindness in these people. While it is true that antisocial behaviour is often linked to a childhood of abuse and deprivation, it is also true that by no means all antisocial attitudes can be attributed to these factors. Many people with fulfilling childhoods behave like real fiends in adulthood. And the reverse is also true.

The other is that anti-social acts, such as nepotism and other forms of corruption, are often deviant forms of pro-social behaviour. Corruption consisting of favouring family and friends from positions of power would be explained by virtue of the tendency to such behaviours, only directed at those closest to the family or social group.

In my opinion, it is futile –and I think counterproductive– to pretend that the normal or natural state of people is that of goodness, that it is normal to behave well with others in a systematic way.

I tend to think that in human groups there is a diversity of natures and that, depending on the circumstances –environmental, including cultural and social– the behaviours rewarded by natural selection are different. The effect of natural selection –also through cultural and social processes of transmission of patterns and values– is what determines which traits are dominant.

After all, I think it would not make much sense for us to think of opposing categories, with their corresponding intermediate degrees and variability within the same person, such as good and evil, were it not for the fact that such categories reflect in our minds the existence of opposing poles that serve as reference points. The way in which the author of this book conceptualises this subject is, in my opinion, just wishful thinking.

Title: The Altruistic Brain. How We are Naturally Good

Author: Donald W. Pfaff

Ed. by Oxford University Press, 2015.