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Authors: Bruce Hood

Tags: #Science, #Life Sciences, #Neuroscience

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BOOK: The Domesticated Brain
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Other animals also live in groups and exhibit a host of social skills for working out what others are thinking, but these abilities are mostly restricted to situations where there is a potential fight or conflict. Most non-human primates are opportunists, only on the lookout for situations where they can take advantage of other members for either food or sex or to establish a better position in the dominance hierarchy. There are examples where chimpanzees will help others, but these are mostly situations where there is the potential for some personal gain.
50
In contrast, people will sacrifice personal gain for others. They will even spontaneously help strangers who they will never meet again. The capacity for altruism seems to be characteristically human. Examples of animal altruism are rare and restricted to those species that exhibit strong codependence, such as marmosets. In these cases, it is strategically in their interests to be promiscuously prosocial to increase their likelihood of breeding.
51

Humans may be opportunists too, but all societies are held together by tacit assumptions of reciprocity and moral codes to prevent individuals taking advantage. These are the rules we abide by. Some of these codes are enshrined as laws. We enter into social contracts where we submit to authority or the state on the assumption that those who abide by the rules will benefit, whereas those who violate or break
them will be punished. Members who benefit from these social arrangements do not even have to be family. Indeed, when you think about it, much human sharing of resources is altruistic – doing good deeds for the benefit of others who remain anonymous without necessarily benefiting ourselves.

No other animal on the planet behaves as altruistically as we humans do. Of course, there are some species, such as worker ants and bees, that make the ultimate sacrifice for the good of the nest or the hive when it comes under attack, but they do so because they are genetically closely related to those that benefit. Evolution has programmed their brains to be self-sacrificial. Humans are different. We cooperate with others because it makes us feel good. It is the thought of helping that is the reward, because we feel connected to the group. These feelings are the emotions that motivate us to be prosocial towards our fellow man (or woman) and fuel the drive towards altruistic collaboration, cooperation and ultimately human culture. However, we are not slavish drones that automatically bend over backwards to help anyone; we are always on the lookout for those who are trying to cheat the systems of reciprocity. We are inclined to lend a hand but we will seek retaliation if we believe we have been wronged. In order to make these sorts of decisions we have to have brains that are sophisticated enough to interpret others in terms of their motives, their goals and their affiliations.

What makes the human brain different?

For many animals, the problems of living long enough to reproduce were basic and immediate – how to navigate the
world to find food, avoid harm and so on. Solitary animals figure these out for themselves because this is how they have evolved. Other animals that live in groups evolved the capability for coordination and cooperation for mutual benefit. For them, the environmental pressures they had to adapt to were not only physical, geographical or climate-based but also social. In a group, there would have been multiple potential mates competing to pass on their genes. This led to the evolution of social behaviours that increased the likelihood of successful breeding within a group.

This increase in social skills is considered one of the reasons that primate brains grew larger and why our species in particular have become the most skilled at interacting and learning from others. But then the human brain began to shrink again with the birth of large civilizations, when we started to live together more peacefully. It could be that humans went further than all other social animals by developing culture – the ability to communicate, to share ideas and knowledge, to engage in ritualistic symbolic activity and develop rules about how to behave for the benefit of the group. We had to learn to live together in greater harmony as our numbers started to increase. We needed to learn to become diplomatic. While physical environments tend to be static, social environments by comparison are constantly changing and providing considerable feedback, which in turn changes the dynamic of the interaction. In short, expertise in social interactions required considerable processing power and flexibility.

To enable humans to do this, we developed long childhoods to provide sufficient time and resources to ensure that
our offspring were educated in the skills necessary for harmonious social living. Why else would humans have evolved into the species that spends the longest proportion of their lives dependent on adults? This amount of time was an evolutionarily big commitment for both parents and their offspring. With domestication came wisdom passed down the generations. We may have taught our own children some basics, but there was more to learn from the group. Our ability to communicate meant that our children could learn more about the world they needed to negotiate by listening to others without having to rediscover everything from first principles. But to benefit from that, the most critical knowledge they learned during childhood was how to be liked and valued by others – in other words, how to behave.

According to available records, the youngest child convicted and executed for a crime in England was John Dean, aged around eight years. He was hanged in Abingdon for setting fire to two barns in the nearby town of Windsor in 1629. At the time, the age of criminal responsibility was seven years, at which point children were considered to be little adults. Indeed, this is how they were often portrayed in paintings from that period.

In Van Dyck’s (1637) portrait of the children of Charles I, they look like miniature adults. Charles II, the boy in the painting, is only seven years old, yet he is shown with the posture of an adult, with feet crossed in a casual lean against the wall. The portrait reflects the prevailing attitude of the time that children simply lacked the wisdom of experience and that with training they would become acceptable to society. Like empty vessels, they needed to be filled up with information and instructed how to behave.

John Locke (1632–1704), the English philosopher, captured this view of the child as a blank canvas:

Let us then suppose the mind to be, as we say, white paper void of all characters without any ideas. How comes it to be furnished? Whence comes it by the vast store which the busy and boundless fancy of man has painted on it with an almost endless variety? Whence has it all the materials of reason and knowledge? To this I answer, in one word, from EXPERIENCE.
1

Figure 1: Children depicted as ‘Little Adults’

Locke described the infant’s mind as a ‘
tabula
rasa
’ or blank slate. Not only was the infant’s mind considered empty, it was one that was faced with the daunting task of making sense of a complex and confusing new world of sensations and experience that the American psychologist William James
would later describe in 1890 as a ‘blooming, buzzing confusion’.
2

However, Locke’s blank slate view is not plausible, nor is the newborn’s world completely confusing as James imagined. As the Prussian philosopher Immanuel Kant
3
(1724–1804) pointed out, blank slates would not work unless they were already set up to detect the structures of the world. There has to be some organization built in in order to determine what constitutes a pattern in the first place. Consider how complicated vision would be without some pre-existing knowledge. You cannot begin to understand the world around you unless you have some inkling of what you are looking for. In order to perceive the world, you need to distinguish objects from backgrounds and determine where one object begins and another ends. We rarely consider these as problems because vision is so effortless. It is only when you try to build a machine that can see that the difficulty becomes all too obvious.

In 1966, Marvin Minsky, one of the pioneers of artificial intelligence, is said to have asked one of his undergraduate students at MIT to ‘spend the summer linking a camera to a computer and getting the computer to describe what it saw’. Presumably Minsky thought that the problem was easy enough that it should take the duration of a summer vacation for a student to solve. That was almost fifty years ago and thousands of professional scientists are still working on how to make machines see like humans.

Back in the 1960s, artificial intelligence was a new field of science that promised us a labour-saving future where robots clean the house, wash the dishes and basically perform all the mundane chores humans hate to do. Since then we have witnessed remarkable developments in computing and technology and there are certainly very smart vacuum cleaners and dishwashers. But we still have not been able to build a robot that perceives the world like a human. They may look human but they are unable to solve some of the simplest problems we take for granted, ones that most babies master before their first birthday.

Another reason why the blank slate cannot be true is because it turns out to be physiologically wrong. Our senses are pre-configured in anticipation of the sorts of signals that we can expect as babies. We do not have to learn to distinguish different colours, or that a boundary between brightness and darkness corresponds to an edge. If you measure from brain cells that react to sensation in unborn animals before they have had any experience of the external world, they will already respond to features that they have not yet encountered.Human newborns will show immediate preferences for
some patterns before they have had any time to learn them, so their world is not totally confusing. These early capabilities show that there is considerable formatting in the newborn’s brain that enables them to make sense of experiences.

Figure 2: Spot the difference

Like a computer that you buy from a store, the brain already comes with an operating system installed. What you eventually store on it really comes down to what you do with it. Biology and experience work together to generate a developing mind, adapted to the external world. That process is one of discovery as each child goes about decoding the complexity of the world around them by using the tools that evolution has bestowed upon them.

Getting wired up

The brain of any animal is as complex as it needs to be to solve the world problems that the creature has evolved to accomplish. In other words, the more versatile an animal’s behaviour, the more sophisticated their brain.
4
This versatility comes from the capacity to learn – storing memories as patterns of electrical connectivity in the specialized brain cells that alter in response to experiences. In the human adult, the brain is comprised of an estimated 170 billion cells, of which 86 billion are neurons.
5
The neuron is the basic building block of the brain’s communication processes that support thoughts and actions.

BOOK: The Domesticated Brain
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