Throughout this chapter, we have focused very much upon abnormalities of volitional experience: the plights of those who have (verifiably, objectively) lost control of their limb movements and those people who experience a disordered ‘sense’ of control, albeit in the presence of relatively preserved movement (at least in terms of its objective appearance). We have seen that human subjects, agents, may be deprived of both their motoric control and their sense of agency (their ‘authorship’ of action). Relatively complex behaviours may arise unbidden (via ‘anarchic hands’) or under the ‘influence’ of ‘external forces’, as when a patient with schizophrenia moves her hand but feels as if she is subject to the play of ‘cosmic strings’.

What may we conclude? Well, at the very least, we might conclude that no account of human action (and, therefore, human moral responsibility) is ever complete in the absence of a subjective report, a ‘view from within’, provided by the agent. Just because behaviours may ‘appear’ purposeful does not mean that they are. Some quite complex behaviours can emerge without their conduit's ‘consent’. So, when we wish to apportion responsibility, we are not merely identifying an organism, a set of bones and joints, muscles and nerves that ‘conveyed’ the pattern of movement to the environment; we are saying something important about ‘its’ underlying volitional processes: the symmetry pertaining between desires and deeds, intentions and actions.

Anarchic and alien motor phenomena of the kinds that we have described seem to arise from structural or functional abnormalities located in several distributed, but no less specific, brain regions, and seem to constitute impairments of agency, mediated via at least two mechanisms:

1. A disinhibition of ‘lower’ motor centres giving rise to relatively stereotypic and contextually inappropriate motor routines (as occurs following medial frontal and callosal lesions); in other words, the kinds of movements that might have ‘given Dr. Strangelove away’;

2. A disturbance in the perception of voluntary movement, so that control of movement (agency) is attributed to an alien entity (phenomena associated with right parietal lobe lesions and epilepsy, and focal hyperactivity in the context of schizophrenia).