The value of electroencephalographic recordings during eserine treatment for overdosage with anticholinergics is discussed, based on the results obtained in 6 cases. The results were spectacular in three cases, and a partial improvement was noted in one other case (suicide attempts with overdoses of atropine compounds), but only a slight effect was observed in two patients (with overdose of neuroleptics). Three points have to be underlined concerning the E.E.G. recordings: --eserine did not cause supplementary E.E.G. changes;--with eserine, the paroxystic abnormalities observed during overdoses of atropine compounds and amitriptyline rapidly disappear;--with mixed overdoses (atropine, barbiturates, or minor tranquillizers), eserine has no effect against non-anticholinergic products. Therapy with eserine, however, is still limited in its indications because of its short period of activity, its side-effects, and the possible risks of cardiac or convulsant complications.