There is a general agreement about the less disruptive effect on memory and the shorter post-treatment confusion after unilateral electroconvulsive therapy (UNI-ECT) as compared with the traditional bifrontotemporal ECT (BI-ECT). However, there are divergent opinions about its therapeutic efficacy.

An intraindividual double-blind cross-over comparison for the anterograde effect on memory of unilateral non-dominant frontofrontal (FF) and temporo-parietal (TP) ECT was performed in connection with the second and third treatment of an ECT-series, the electrode placement being alternated at random. Treatment technique was standardized and seizure duration was measured by means of EEG. Memory functions were tested after treatments by means of four memory tests: the 30 Word-Pair Test, the 30 Figure Test, the 30 Geometrical Figure Test and the 30 Face Test. Three operationally defined memory variables, immediate memory (IMS, 3 hours after ECT), delayed memory (DMS, 3 hours after IMS), and their difference, forgetting, were scored. No differences were found in the mean time of electrical stimulation, in the amount of methohexital and suxamethonium chloride, and in seizure duration between the two treatment groups. No statistically significant differences in any of the memory tests were found. The FF electrode position did not show any advantage compared with the routine TP electrode placement.

An intraindividual, double-blind cross-over comparison of the effects of dominant (D) and non-dominant (ND) temporo-parietal unilateral electroconvulsive therapy (ECT) was performed in connection with the second and third treatment, the type of electrode placement being allocated at random. Four memory tests were used. The 30 Word-Pair Test is an audio-visual verbal recall test, the 30 Figure Test is a mainly visual recognition test with easily verbalized items. The 30 Geometrical Figure Test and the 30 Face Test are nonverbal recognition tests of visual complex and unfamiliar material. Compared with dominant ECT, non-dominant ECT has a more negative influence in the complex non-verbal visual tests, whereas dominant ECT has a more negative effect on verbal memory. In the non-verbal tests, as compared with the verbal ones, the encoding (or learning) is relatively more influenced and the retention (or storage) relatively less. An impairment either of complex apperceptive function or of memory may be responsible for the relatively lower performance in non-verbal tests after non-dominant ECT.

Trials performed do not provide evidence for an antidepressant effect of 5-HTP. L-TP, without interacting pharmaca, does not appear to be a well-documented antidepressant. The only convincing evidence for L-TP as an antidepressant is that L-TP enhances the effect of MAOI.