RETRODUCTIVE REASONING IN A PROPOSED SUBTYPE OF PARTIAL SEIZURES, EVOKED BY LIMBIC KINDLING

This analysis provides a specific example of the generally applicable process of creative delineation of a novel pattern while searching for an explanatory hypothesis for puzzling observations. In so doing, the neglected retroductive form of inference or abduction was used. Centr al to such a process is the delineation of a specific ''generative mec hanism'' capable of uniting and explaining heretofore unexplained phen omena. Herein the neurophysiologically known mechanism of limbic seizu re ''kindling'' is offered as a unifying explanation for a dozen bizar re phenomena, proposed as a new subtype of partial seizures, ''Limbic Psychotic Trigger Reaction.'' This new syndrome has been proposed over 15 years in 17 male social loners. Upon encounter with an individuali zed stimulus, which revived in memory prior moderately hurtful experie nces, these men suddenly committed motiveless, unplanned acts with fla t affect, transient psychosis and autonomic arousal, showing no quanti tative impairment of consciousness and so without memory loss for thei r perplexing homicidal acts (13 cases), firesetting (3 cases), or bank robbery (1 case). Events occurred in three phases reminiscent of seiz ures: (1) aura-like puzzlement, (2) transient ictus with a limbic rele ase of predatory or defensive aggression (circa 20 min.), and (3) post ictal inefficient actions, implicating a transient frontal lobe system dysfunction secondary to the limbic hyperactivation. The 17 men were of diverse backgrounds, but all without history of prior violence or s evere emotional trauma. Seven of 17 had some abnormal brain tests at s ome time during their lives and eight known histories of typically ove rlooked closed-brain injury. Brain damage may facilitate seizure ''kin dling'' but has been traditionally observed in mammals and in a few hu mans without such damage.