The cultural evolution of mind reading

Background We use “theory of mind” or “mind reading” to understand our own thoughts and feelings and those of other agents. Mind reading has been a focus of philosophical interest for centuries and of intensive scientific inquiry for 35 years. It plays a pivotal role in human social interaction and communication. Mind reading allows us to predict, explain, mold, and manipulate each other’s behavior in ways that go well beyond the capabilities of other animals; therefore, mind reading is crucial to understanding what it means to be human. In many respects, the capacity to read minds is like the capacity to read print: It involves the derivation of meaning from signs, depends on dedicated brain mechanisms, is subject to specific developmental disorders, shows cultural variation as well as cultural commonality, and has both interpretive (reading) and regulative (writing) functions. However, recent studies of mind reading in young infants suggest that, unlike print reading, mind reading develops very early in human ontogeny. Learning to read minds is like learning to read print. The acquisition of explicit mind reading is a slow, effortful process in which a novice develops an important, culture-specific skill through expert tuition. Experts facilitate development by directing the novice’s attention to signs that the novice is on the edge of understanding, as well as by explaining in conversation how these signs relate to their meaning. Advances In nonverbal tests of mind reading, infants’ eye movements have been taken as evidence that infants expect an agent to reach toward a location where he or she believes a desirable object to be hidden, even when the agent’s belief is false. This “implicit” mind reading could indicate that humans genetically inherit the specialized neurocognitive mechanisms used for “explicit,” verbally mediated mind reading in adulthood. However, recent research with adults shows that, unlike explicit mind reading, implicit mind reading does not make demands on executive function. This indicates that, although they may be genetically inherited, the mechanisms that mediate implicit mind reading, whether specialized or general-purpose, are distinct from those controlling explicit mind reading. Furthermore, studies of twins, people with hearing impairments, and children from non-Western cultures, as well as typically developing Western children, suggest that, like print reading, explicit mind reading is culturally inherited. Rather than being constructed by simulation or theory-testing, explicit mind reading is a skill that is passed from one generation to the next by verbal instruction. Most, possibly all, human neurocognitive skills are shaped by culture and many are culturally inherited, but the parallels between mind reading and print reading are extraordinary. In contrast, whereas linguistic communities vary in the ways that they categorize colors, color perception is not culturally inherited in the same way as print reading. Unlike print reading, color perception is rooted in highly specialized, genetically inherited mechanisms that humans share with other species. Though cultural input adjusts these mechanisms, it does not make them into a whole new neurocognitive system. Outlook The cultural evolutionary account of mind reading does not imply that mental states are mere fictions, but it does suggest that any aspect of mind reading—even those relating to knowledge and primary emotions—could show substantial cultural variation. More cross-cultural studies using sensitively translated test procedures are needed to chart extant variation. Similarly, although the cultural evolutionary account suggests that humans do not genetically inherit mechanisms that are specialized for the representation of mental states, it assumes that, as in the case of print reading, many of the neurocognitive raw materials for explicit mind reading are inborn. Therefore, priorities for future research are to identify the genetic “start-up kits” for both implicit and explicit mind reading and to find out exactly how the products of the former contribute to the development of the latter. Our view suggests that, like print reading, mind reading is a culturally inherited skill that facilitates the cultural inheritance of other, more specific skills; mind reading is a cultural gift that keeps on giving. Learning to read minds starts early No parent needs reminding that children are born with a surprising set of abilities. But children still need many hours of guidance and instruction. Heyes and Frith review one particular social cognitive skill: reading the minds of others (or at least working out what other people are thinking and feeling). An unrefined capacity for “mind reading” is present in infants, but teaching is necessary to develop the full-blown capacity seen in adults. The authors draw parallels between learning to read and learning to read minds. Science, this issue p. 10.1126/science.1243091 It is not just a manner of speaking: “Mind reading,” or working out what others are thinking and feeling, is markedly similar to print reading. Both of these distinctly human skills recover meaning from signs, depend on dedicated cortical areas, are subject to genetically heritable disorders, show cultural variation around a universal core, and regulate how people behave. But when it comes to development, the evidence is conflicting. Some studies show that, like learning to read print, learning to read minds is a long, hard process that depends on tuition. Others indicate that even very young, nonliterate infants are already capable of mind reading. Here, we propose a resolution to this conflict. We suggest that infants are equipped with neurocognitive mechanisms that yield accurate expectations about behavior (“automatic” or “implicit” mind reading), whereas “explicit” mind reading, like literacy, is a culturally inherited skill; it is passed from one generation to the next by verbal instruction.