International audience Despite the intensive study of morphological effects with various on-linetechniques such as masked priming, psycholinguistics did not manage so far to present a consensual framework, and are still divided on the nature and the locus of morphology in the mental lexicon. In this contribution, we propose to focus on three issues related to morphological effects which have not been given the right importance so far: the implications of studying morphology through nonwords, the role of frequency of the lexical items used as materials, and finally the role of a novel variable measuring the influence of formally related but morphologically unrelated word forms on processing, i.e. the pseudo-relatives. The experiment presented here provides evidence in favour of these two variables. We propose a revised model of morphological processing, sensitive to lexical (e.g. frequency) and exo-lexical characteristics of the stimuli (e.g. pseudofamily size), capable to cope with various effects induced by true morphological relatives and pseudorelatives, as well as for surface effects, such as the pseudoderivation effect.