The psychology of self is the study of either the cognitive and affective representation of one's identity or the subject of experience. The earliest formulation of the self in modern psychology forms the distinction between the self as I, the subjective knower, and the self as Me, the subject that is known. Current views of the self in psychology position the self as playing an integral part in human motivation, cognition, affect, and social identity. Self following from John Locke has been seen as a product of episodic memory but research upon those with amnesia find they have a coherent sense of self based upon preserved conceptual autobiographical knowledge. It is increasingly possible to correlate cognitive and affective experience of self with neural processes. A goal of this ongoing research is to provide grounding and insight into the elements of which the complex multiply situated selves of human identity are composed. The 'Disorders of the Self' have also been extensively studied by psychiatrists.