The mind and brain sciences began with consciousness as a central concern. But for much of the 20th century, ideological and methodological concerns relegated its empirical study to the margins. Since the 1990s, studying consciousness has regained a legitimacy and momentum befitting its status as the primary feature of our mental lives. Nowadays, consciousness science encompasses a rich interdisciplinary mixture drawing together philosophical, theoretical, computational, experimental, and clinical perspectives, with neuroscience its central discipline. Researchers have learned a great deal about the neural mechanisms underlying global states of consciousness, distinctions between conscious and unconscious perception, and self-consciousness. Further progress will depend on specifying closer explanatory mappings between (first-person subjective) phenomenological descriptions and (third-person objective) descriptions of (embodied and embedded) neuronal mechanisms. Such progress will help reframe our understanding of our place in nature and accelerate clinical approaches to a wide range of psychiatric and neurological disorders.

Introduction The relationship between subjective conscious experience and its biophysical basis has always been a defining question for the mind and brain sciences. But, at various times since the beginnings of neuroscience as a discipline, the explicit study of consciousness has been either treated as fringe or excluded altogether. Looking back over the past 50 years, these extremes of attitude are well represented. Roger Sperry (1969), pioneer of split-brain operations and of what can now be called ‘consciousness science’ lamented in 1969 that ‘[m]ost behavioral scientists today, and brain researchers in particular, have little use for consciousness’ (p. 532). Presciently, in the same article he highlighted the need for new technologies able to record the ‘pattern dynamics of brain activity’ in elucidating the neural basis of consciousness. Indeed, modern neuroimaging methods have had a transformative impact on consciousness science, as they have on cognitive neuroscience generally. Informally, consciousness science over the last 50 years can be divided into two epochs. From the mid-1960s until around 1990 the fringe view held sway, though with several notable exceptions. Then, from the late 1980s and early 1990s, first a trickle and more recently a deluge of research into the brain basis of consciousness, a transition catalysed by – among other things – the activities of certain high-profile scientists (e.g. the Nobel laureates Francis Crick and Gerald Edelman) and by the maturation of modern neuroimaging methods, as anticipated by Sperry. Today, students of neuroscience – for the most part – feel able to declare (or deny) a primary interest in studying consciousness. There are academic societies and conferences going back more than 20 years and scholarly journals dedicated to the topic. Above all, there is growing a body of empirical and theoretical work drawing ever closer connections between the properties of subjective experience and the operations of the densely complex neural circuits, embodied in bodies embedded in environments that together give rise to the apparent miracle of consciousness. We cannot yet know whether today’s students will find the solution to the ‘problem of consciousness’ or whether the problem as currently set forth is simply misconceived. Either way, there is much more to be discovered about the relations between the brain and consciousness, and with these discoveries will come new clinical approaches in neurology and psychiatry, as well as a new appreciation of our place as part of, and not apart from, the rest of nature.

Declaration of conflicting interests

The author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article. Funding

I am grateful to the Dr Mortimer and Theresa Sackler Foundation which supports the Sackler Centre for Consciousness Science. I also acknowledge support from the Wellcome Trust (Engagement Fellowship) and the Canadian Institute for Advanced Research, Azrieli Programme on Brain, Mind, and Consciousness.