Hood, Bruce - Supersense

Okay, so you’re an expert now. Try to say the colour of the word in the next list as fast as you can.

Did you make any mistakes? Maybe not, but I bet you had a problem and were much slower. The act of reading triggers the impulse to utter the word as read, but if the word conflicts with the correct answer, that response has to be ignored in order to state the colour. On the other hand, naming a colour is not automatically triggered by reading. So saying the word needs to be suppressed or inhibited in order to make the correct response. This is why inhibition is necessary for planning and controlling behaviour: it enables you to avoid thoughts and actions that get in the way of achieving your goals.

Finally in order to benefit from all this executive function, we need to evaluate our performance. As we saw earlier, adaptive behaviour can help us learn from past successes and mistakes. Remember Damasio’s frontally damaged patients in chapter 2 who were unable to play the gambling game successfully? They lacked the necessary evaluation of the hidden rules controlling the rewards. The system that learns from the past and helps us to make decisions about the future includes the DLPC. One of the main neurotransmitter systems of the DLPC is . . . yes, that’s right . . . dopamine. This may all be too convenient and simplistic, and it may be my supersense of connectedness at work, but there does appear to be a coherent pattern emerging.

We now think that brain changes in the DLPC have important implications for child development and advances in reasoning. 49Control of behaviours, thoughts, reasoning, and decision-making – in short, just about every aspect of higher intelligence that humans possess – is dependent on the executive functions of the DLPC. As we develop into adults, we become increasingly more in control of our urges, and that requires the activity of the DLPC. For example, do you remember falling objects? Which falls faster, a heavy object or a lighter one? We intuitively think that heavier objects should fall faster and are surprised if they don’t. When adults learn that this belief is wrong, measurements of their brains while they think about the problem reveal that their DLPC is active. 50When adults reason about the Linda problem from chapter 3 and consider whether she is more likely to be a bank worker or a feminist, their DLPC is active trying to suppress the tendency to go for the most obvious intuitive answer. 51Even when they give the correct answer, the old childish naive theories are still active and must be suppressed. Bad ideas don’t go away. They hang around and have to be ignored!

However, like many functions of the human body, there is a progressive decline in executive functions towards old age Many of the popular mind puzzles, like Sudoku or the current fad for ‘brain training’ computer games, tap into DLPC abilities. When they claim that they can measure how old your brain is, they do this by comparing your performance on tasks dependent on the DLPC to the normal range that can be expected for people of different ages. That’s because DLPC function changes with age.

One consequence of the loss of DLPC control in an adult is reverting back to behaving and thinking like a young child. Whenever this system is impaired through ageing, damage, or disease, the ability to remember, inhibit, plan, and evaluate is compromised. We forget things. We all know elderly relatives who seem to become socially embarrassing in their lack of control. Planning a trip becomes a chore. We may lose the ability to make rational, balanced judgements and leave all our inheritance money to ‘that nice lawyer who has been ever so helpful’. Old age does not guarantee wisdom.

THE CRUELLEST DISEASE

For all too many of us entering old age, there can be a much more devastating and progressive slide into decline as we lose DLPC functions. Alzheimer’s disease is often considered the cruellest of diseases. The change in personality is the most distressing aspect of the illness. Someone you have spent your life knowing and loving turns into a complete stranger who needs the attention and care of a small child. Alzheimer’s is a neurodegenerative disorder, which means that it primarily destroys the higher functions that control behaviour and thinking. It starts off with absentmindedness. Then there are unprovoked violent outbursts, and inappropriate behaviour can alert family members that things are not quite right. The problem with diagnosing the onset of Alzheimer’s is that as we age we all change in our personality. We can become forgetful, disinhibited, grumpy, and so on, but Alzheimer’s disassembles the individual to the extent that he or she becomes unrecognizable to family and friends.

Recently, research on Alzheimer’s has provided unexpected evidence for the supersense. Before adults with Alzheimer’s reach a state of advanced decline, they display signs that the mind never truly abandons childish ways of reasoning. 52For example, when asked, ‘Why are there trees?’ ‘Why is the sun bright?’ or ‘Why is there rain?’ patients give answers just like young children. They say trees are for shade, the sun is bright so that we can see, and rain is for drinking and growing. They have gone back to the teleological thinking of the seven-year-old we saw in chapter 5. They also become animists again, attributing life to nonliving things like the sun. It’s not the case that they have forgotten everything they know. 53Rather, the errors they make reflect the intuitive theories of children. Dementia shows that intuitive thinking is not abandoned but suppressed by the higher centres of the brain as we grow into adults. When that ability to inhibit is lost, the intuitive theories reappear.

BEING IN TWO MINDS

Psychologists have come to the conclusion that there are at least two different systems operating when it comes to thinking and reasoning. 54One system is believed to be evolutionarily more ancient in terms of human development; it has been called intuitive, natural, automatic, heuristic, and implicit. It’s the system that we think is operating in young children before they reach school age. The second system is one that is believed to be more recent in human evolution; it permits logical reasoning but is limited by executive functions. It requires working memory, planning, inhibition, and evaluation. This second reasoning system has been called conceptual–logical, analytical–rational, deliberative–effortful–intentional–systematic, and explicit. It emerges much later in development and underpins the capacity of the child to perform logical, rational problem-solving. When we reason about the world using these two systems, they may sometimes work in competition with each other. The rational system is slow and ponderous. It’s not very good at coming up with snappy decisions. Also if you preoccupy your rational system with problem-solving that uses up your executive functions, then the intuitive mechanisms can run amok. That’s why people under stress and time constraints often default to the intuitive system that is more effortless. When this happens we make all sorts of supersense judgements.

The supersense we experience as adults is the remnant of the child’s intuitive reasoning system that incorrectly comes up with explanations that do not fit rational models of the world. One might assume that those prone to the supersense and belief in the paranormal are lacking in rational thought processes, but that would be too simplistic. Studies reveal that the two systems of thinking, the intuitive and the rational, coexist in the same individual. There are, in effect, two different ways of interpreting the world. In fact, when we measure reliance on intuition, no relationship has been found with intelligence. Intuitive people are not more stupid. 55They are, however, more prone to supernatural belief. One recent study found that mood is an important factor in triggering supernatural beliefs in those who score more highly on measures of intuition. 56For example, happy, intuitive adults are more likely to sit farther away from someone they believe is contaminated, a response that reflects the psychological contamination we described in chapter 7. They are also less able to throw darts at pictures of babies; this measure reflects the sympathetic magical law of similarity by which objects that resemble each other are believed to share a magical connection. Even though individuals may not be consciously aware of the thought processes guiding such behaviour, these effects reveal a deep-seated notion of sympathetic magical reasoning. The supersense lingers in the back of our minds, influencing our behaviours and thoughts, and our mood may play a triggering role. This explains why perfectly rational, highly educated individuals can still hold supernatural beliefs.