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Human volition: towards a neuroscience of will

Nature Reviews Neuroscience volume 9, pages 934946 (2008) | Download Citation

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Abstract

The capacity for voluntary action is seen as essential to human nature. Yet neuroscience and behaviourist psychology have traditionally dismissed the topic as unscientific, perhaps because the mechanisms that cause actions have long been unclear. However, new research has identified networks of brain areas, including the pre-supplementary motor area, the anterior prefrontal cortex and the parietal cortex, that underlie voluntary action. These areas generate information for forthcoming actions, and also cause the distinctive conscious experience of intending to act and then controlling one's own actions. Volition consists of a series of decisions regarding whether to act, what action to perform and when to perform it. Neuroscientific accounts of voluntary action may inform debates about the nature of individual responsibility.

Key points

  • A voluntary action is a motor act, the occurrence, form and timing of which are generated internally rather than by an immediate external stimulus.

  • Voluntary actions involve a characteristic network of brain motor areas, including the basal ganglia, the pre-supplementary motor area and the parietal lobes.

  • The computations that are performed by this network can be divided into three types of decisions: whether to act, what action to perform and when to perform it.

  • Neural preparation of voluntary action is accompanied by a particular subjective experience that is best described as 'conscious intention'. Conscious intention provides a predictive experience of current actions and contributes to the sense of controlling our actions and, through them, the world around us.

  • Clearer cognitive models of the information processing that is involved in voluntary actions, and new neural data about the brain areas that perform these processes, are making voluntary action amenable to scientific study for the first time.

  • Advances in understanding voluntary action provide the starting point for a neuroscientific approach to one of the fundamental aspects of being human. This will in turn allow better understanding of failures of volition in both neurological and psychiatric illnesses.

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Acknowledgements

Writing of this article was supported by generous grants and Fellowships from The Leverhulme Trust, The Royal Society and the Economic and Social Research Council.

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  1. Institute of Cognitive Neuroscience, University College London, London, WC1N 3AR, UK.  p.haggard@ucl.ac.uk

    • Patrick Haggard

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https://doi.org/10.1038/nrn2497

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