Madness Explained

by Richard P. Bental

  Mentalizing or ToM skills are usually assessed by means of tests in which the individual is required to infer that someone else holds a false belief about the world. A simple example used with children is the so-called ‘Sally–Ann’ test in which a story is enacted with two dolls, Sally and Ann, who are shown with two boxes, one of which contains an object. In the story, Sally leaves the room, and Ann switches the object from one box to the other. The child who is being tested is then asked to say in which box Sally looks for the object when she returns. In order to answer this question correctly it is, of course, necessary to understand that Sally’s belief about the world when she returns is at variance with reality. Ordinary children begin to pass this kind of test during their fourth year of life (although they may show evidence of more rudimentary mentalizing skills – for example, the ability to direct the gaze of others, or to distinguish between pretend and reality – as young as 2 years of age).36 In autistic children, the development of mentalizing skills is severely delayed, and perhaps permanently impaired, even though they may perform normally on other types of tests.37

  It is possible to draw two important conclusions from these findings. First, the terrible consequences of the autistic person’s inability to understand the minds of others demonstrates how important social cognition is in everyday life. Second, the fact that many autistic children score relatively normally on conventional IQ tests suggests that at least one type of social cognition may be relatively independent of the kind of gross cognitive abilities usually measured by psychologists investigating psychosis.

  Uniquely Human

  Many psychologists have proposed that the human mind’s specific ability to deal with social information reflects the evolution of specific mental modules dedicated to this purpose. On this view, there may be, for example, brain modules dedicated to recognizing faces, detecting the emotional states of other people, guessing their intentions, and predicting what they will do. This view is taken by many researchers studying autism, mainly because of the striking evidence that ToM skills can be severely impaired in individuals of average or above average intelligence.38

  In fact, evidence that the mind is organized in this way is far from clear cut. The American philosopher Jerry Fodor has suggested several criteria that might be used to identify modular information-processing systems. He has argued, for example, that they are unconscious, respond quickly and in an obligatory fashion (predetermined inputs lead to predetermined outputs), develop in a characteristic sequence in the child, are neurologically localized (that is, implemented by dedicated neural circuits), and deal with only specific types of information.39 However, many of these characteristics are true of acquired skills that have been practised to the point of becoming automatic. For example, champion chess players often choose moves intuitively, without being aware of the mental processes that guide their decisions. As the ability to master chess no doubt depends on the individual’s level of cognitive development, it is likely that children learning chess from an early age will develop their skills in a characteristic sequence. Moreover, functional neuroimaging studies have shown that specific areas of the brain ‘light up’ as grand masters progress through a game.40 Despite these observations, it obviously would be a mistake to assume that the human brain has evolved a chess-playing module.

  A more serious problem for extreme versions of modularism concerns the relationship between genes and brain circuits.41 Presumably, the modular architecture of the brain is determined genetically. However, as I completed this chapter, the latest estimate of the number of genes in the human genome (calculated as the Human Genome Project came towards an end) was 30,000, whereas there may be up to 100,000,000,000,000 synapses in the human brain. For this reason, it is simply not plausible that neural circuits are precisely predetermined by the genetic code. Of course, this argument does not imply that there can be nothing module-like in the human brain – modules may develop without the precise genetic specification of specific circuits. However, it does suggest that the development of the neural circuits responsible for social cognition, whether or not they are ultimately organized into discrete modules, must depend on complex interactions between the developing individual and the environment. In later chapters of this book, we will see that this observation has some important implications for our understanding of the origins of psychosis.

  Perhaps the human faculty that has the best claim to being modularized is language. As we have already seen, there is extensive evidence that specific regions of the brain are involved in generating and understanding speech. Moreover, the fact that language is a species-specific ability strongly suggests that the development of this ability is genetically controlled.42 Even so, the environment also plays an obvious role. Children grow up to speak the language they hear from their care-givers rather than the language of their ancestors. Children who are not exposed to the speech of others as their brains develop grow up to be, tragically, severely linguistically and intellectually disabled in later life.43

  The ability to speak has a profound effect on all other aspects of the human mind, and therefore must be considered when we attempt to understand the role of cognition in psychosis. When thinking about the function language plays in human life, it is only natural to regard it as a means by which information is passed from one individual to another. Psychologists who have speculated about the origins of language have usually assumed that the advantages thereby conferred provided the major selection pressure for language evolution.44 For example, it has been argued that language evolved because it enabled our ancestors to cope with the complex relationships entailed by our membership of large social groups.45 Another, not incompatible suggestion is that our rapid specialization for language was fuelled by some kind of evolutionary arms race.46 The ape-like ancestor who can say to another something like, ‘Hide behind that rock over there, jump out with your stick and attack the intruder as he passes by!’ is clearly going to have better survival prospects than one who lacks this skill. However, even this simple example suggests that language also has an intellectual function. By framing problems in a verbal form we can organize our ideas, and plan what we are going to do.

  When I was young, it was commonly said that talking to oneself was the first sign of madness, but a case can be made for asserting the opposite. I think all readers will be aware of the internal dialogue that runs through the mind from the moment of waking until sleep resumes. Talking to ourselves, we debate events, plan actions, issue chastisements to ourselves when things go wrong and exclaim inwardly with delight when things go well. While it is certainly not the case that the stream of consciousness is entirely verbal, for much of the time our thoughts are dominated by words.

  The intellectual function of language was recognized in the early years of the twentieth century by the Russian physiologist and psychologist Ivan Pavlov. Pavlov argued that this use of words has conferred on human beings mental powers that separate us from other species. Because we can think in words, we are to some extent free from being controlled by the simple conditioning processes that dominate the behaviour of non-human animals.* Building on this idea, his student Lev Vygotsky studied the way in which communicative speech is transformed into verbal thought. Unfortunately, because he died of tuberculosis at the age of 37 in 1934, and because Stalin suppressed his work, Vygotsky’s observations did not become known to Western child psychologists until the early 1960s.

  In his now famous book Thought and Language,47 Vygotsky summarized the relationship between language and thought at different stages of child development as follows:

  1) In their… development, thought and speech have different roots. 2) In the speech development of the child, we can certainly establish a preintellectual stage, and in his thought development, a prelinguistic stage. 3) Up to a certain point in time, the two different lines grow independently of each other. 4) At a certain point these lines meet, whereupon thought becomes verbal and speech rational.

  Vygotsky stu
died the different ways that children make use of language, in order to discover the psychological processes involved in this merging of the lines of thought and speech. He observed that the growing child first learns to produce and understand speech in the context of his relationship with caregivers. During this stage, the child and adult are constantly issuing instructions or asking questions of each other so that, for the child, the whole process of speaking becomes bound up with attempts by the two parties to control each other’s actions. Later, towards the end of the second year of life, children discover that they can instruct themselves by speaking aloud about what they are doing. (This is often preceded by a period in which they ask questions of their parents and then immediately answer for themselves.)48 At this stage, children spend a lot of time talking to themselves out loud (a phenomenon known as private speech) and language becomes a powerful mechanism for self-regulation. Finally, at about the age of 4 years, social and private speech become differentiated from each other. Children of this age learn the neat trick of talking silently to themselves, resulting in inner speech that is inaudible and undetectable to others.

  During the 1920s, Jean Piaget disagreed with this account because he was reluctant to believe that the private speech of 2-year-olds had an intellectual function. Piaget believed that young children talk out loud when on their own because they are too egocentric to realize that no one is listening to them.49 However, observational studies of children have consistently supported Vygotsky’s contention that the young child who talks when on his own is communicating effectively with the person who really matters – himself.50 Moreover, recent studies by American developmental psychologist Laura Berk have confirmed that children who can use private speech effectively when learning new skills acquire those skills most quickly.51

  By adulthood, inner speech has lost many of the characteristics of social speech, and become a highly condensed form of silent verbal activity. When using inner speech, we rarely have to state the subject of our thoughts, because it is already known to us. Elements of speech that allow propositions to be linked meaningfully together so that they appear coherent to the listener (known to linguists as cohesive ties) become redundant. At the same time, inner words expand their symbolic function and develop multiple and complex associations. Although the measurement of this kind of thinking is fraught with difficulty,52 studies in which immediate recollections of inner speech have been compared with the full expression of the same thoughts have suggested that one minute of inner speech can equal up to 4000 words of overt speech.53

  As we spend much of our time talking about ourselves to ourselves, inner speech is an important vehicle of self-awareness.54 It tends to be evoked in social situations that are personally challenging or emotionally arousing. In some circumstances during adult life, we may lazily forget the habit of silent speech acquired during childhood, and speak out loud. This may happen if we have a particularly demanding task to perform (I have been intermittently mumbling to myself while writing this book), when we are under stress, or when we think we are alone (anyone doubting this should stand by a roadway intersection and watch unaccompanied drivers talking to themselves as they wait for traffic lights to change). However, even when we speak silently to ourselves, there is a neuromuscular echo of the time in childhood when we could only speak aloud. Surprising though it may seem, when we think in words, our lips and speech muscles are active.

  The idea that activity in the speech muscles accompanies verbal thought is almost as old as the idea of inner speech itself. The American behaviourist J. B. Watson tried to measure this activity in the 1920s, but his efforts failed because he had inadequate equipment (he experimented with comical devices that used wires and pulleys connected to suction caps fastened on the lips). The invention shortly afterwards of a device, known as an electromyogram (EMG), which directly measures electrical activity in the muscles, soon led to the unequivocal detection of subvocalization, as this silent activation of the speech muscles is now called. In a typical electromyographic study, electrodes are attached to the lips and larynx in order to measure electrical currents in the muscles beneath the skin. Sometimes electrodes are also attached to non-speech muscles (for example, the pectorals) in order to ensure that any increase in muscle activity is limited to those involved in speech. The participant in the experiment is then asked to perform various mental tasks. Countless EMG experiments conducted in the past fifty years or so have demonstrated that subvocalization* accompanies virtually any kind of mental process that requires us to think in words.55 (Interestingly, both psychological and EMG studies have shown that deaf people who have acquired sign language use inner speech in the form of silent signs. As they think, microcurrents are detectable in their finger muscles.)56

  Not surprisingly, in adults subvocalization is particularly evident when we think about ourselves, or when we are ruminating about matters that are emotionally important to us.57 As we have seen, it is precisely these circumstances that most readily elicit inner speech.

  The Brain and its Self

  I want to conclude this brief tour of the human mind by considering a topic that, until recently, has been regarded as more the province of philosophers than psychologists. Indeed, to any hard-nosed biological scientists reading this book, ‘the self’ may still seem a vague and almost metaphysical concept. However, we will see that it can be subjected to scientific analysis.

  In a commendably concise attempt to shed light on the nature of the self, the American social psychologist Roy Baumeister has made the following observation:

  Providing a satisfactory definition of the self has proven fiendishly difficult. It is what you mean when you say ‘I’. Most people use ‘I’ and ‘self’ many times each day, and so most people have a secure understanding of what the self is – but articulating that understanding is not easy.58

  It would be wrong, therefore, to regard the self as a thing, as supposed by Cartesian dualists. It is instead a set of ideas, pictures, or beliefs (or, to use a generic term, mental representations) about who we are. Some of these representations are explicit and available for contemplation, but others are implicit and take the form of vague assumptions or ‘schemas’. Like most mental representations, the self has fluid boundaries and overlaps with other kinds of thoughts and feelings, which is why it defies precise definition. When we talk about or imagine ourselves, we can generate verbal descriptions of our attributes, talents and deficiencies; remember defining moments in our lives; consider how we match or fail to match our moral, social and material aspirations; contemplate the quality of our relationships; compare ourselves to other people; and imagine how those other people see us. Each of these activities evokes one or more aspects of the self but none encompasses the self in its entirety. To borrow a metaphor from the philosopher Dan Dennett, the self is the centre of narrative gravity, which, like the centre of gravity of a physical body, cannot be isolated and touched, but around which our memories, the stories we tell about ourselves, and the decisions we make, all revolve.59

  The pivotal role of the self in human cognition is demonstrated by a deceptively simple phenomenon, known as the self-reference effect. Our ability to remember information depends on how we ‘encode’ information when we encounter it. For example, if we look at a list of words, we can pay attention to whether they are written in upper- or lower-case letters (feature encoding) or what the words actually mean (semantic encoding). In general, we will tend to recall more of the information if we pay attention to its meaning. However, it seems that people are most likely to recall information later if they encode it according to its relevance to the self.60 For example, if we are asked to fill in a questionnaire about our own personality characteristics, and we are then given a surprise memory test of the items on the questionnaire, we will tend to remember the questions we answered ‘yes’ to. The brain, it seems, prioritizes the processing of information that is perceived to be important to the self.

  Because we do not arrive in the
world knowing who we are and how we are different from other people, it is pretty obvious that there must be a developmental story to tell about the self. Some child psychologists have traced its origins to the first few weeks of life, when the infant initially learns to distinguish between himself and his caregiver during ‘proto-conversational’ exchanges that precede the emergence of language.61 Once we can speak, we acquire increasingly elaborate descriptions of the self, some of which we learn from what we are told about ourselves by significant others, and some of which we tell ourselves as we contemplate our triumphs and disasters. Alongside these descriptions, we accumulate memories of what has happened to us and the things that we have done. This stored reservoir of knowledge about the self is the bedrock from which all other aspects of the self are derived. It allows us to define our individual identity (‘I am a slightly overweight family man with a good sense of humour’); our membership of groups of like-minded people (‘I belong to the tribe of clinical psychologists’); claim our rights (‘I want my medical colleagues to acknowledge the wisdom of my views about madness’); plan our future achievements (‘I have the skills and motivation to write a book’); and acknowledge our limitations (‘… but not to climb Mount Everest’).