The aim of this thesis was to study the effects of emotions, through the induction of an emotional state, on the writing processes, spelling performances and working memory capacities in children in school context. More specifically, in relation to the model developed by Ellis and Ashbrook (Resource Allocation Model of Cognitive Interference, 1988) and subsequently modified by Ellis and Moore (1999), the thesis that the cognitive resources available could vary depending on the emotional state of the participant was supported. The influence of emotions (positive, negative and neutral) was tested on the exercise of writing text, dictation and on phonological working memory, in 4th and 5th graders.The results showed that negative emotions were responsible for variations in the length of text and the use of vocabulary in the writing processes (experiment 1), and also of a decrease in performances in phonological working memory (Experiment 3). In contrast, the induction of a positive or negative emotion was responsible for a disturbance in terms of orthographic processes resulting in an increase in the number of spelling errors during dictation (experiment 2 ). In conclusion, it was showed that emotions could have a disruptive effect on some complex cognitive processes in children. In addition, this work also allowed questioning the effect of school activities on the affective states in 3rd and 5th graders (experiment 4). It has been shown that the affective states varies greatly according to the age of children and activity practiced (listening to a text and dictation), but also that the initial affective states were correlated with performances in dictation.
