Jackson's law

   The eponym Jackson's law refers to the British neurologist John Hughlings-Jackson (1835-1911). It involves the notion that a loss of mental functions due to disease retraces in reverse order the evolutionary development of the brain. Jackson hypothesizes that the loss of 'higher' cerebral functions may be brought about by a retrograde evolutionary process called dissolution. The concomitant loss of normal functioning is referred to by him as 'negative symptomatology' and the release of phenomena from the brain's more 'primitive' centres as 'positive symptomatology'. Thus he argues that hallucinations and other positive symptoms might well originate from the normal activity of the brain's 'lower' (i.e. evolutionary 'older') centres. Jackson's law proved an eminent source of inspiration for the "perceptual release theory and for related hypothetical models for the mediation ofhallucinations.

   References

   Hughlings-Jackson, J. (1888). Remarks on evolution and dissolution of the nervous system. American Journal of Psychology, 1, 336-338.