P8.12 Effects of neurofeedback on EEG alpha power and attention span
Objectives: We used online interference by repetitive transcranial magnetic stimulation (rTMS) to evaluate whether the lateral parietal cortex (PC) is involved in Eureka effect, as suggested by neuroimaging data. Methods and Results: Thirty nine healthy volunteers were included in the study. Ten Hz rTMS of the right and left PC was delivered at the intrapatietal sulcus using an optically tracked neuronavigational system. An intensity of 90% resting motor threshold was employed. RTMS of the PC did not affect recognition of degraded pictures representing objects and animals when displayed 2 s after the presentation of their undegraded version (learning phase) However, rTMS delivered over either right or left PC simultaneously to the undegraded image presentation, disrupted identification of the degraded version of the same pictures when displayed 30 minutes after the learning phase. In contrast, recognition of degraded images was unaffected by rTMS over the vertex or by sham rTMS, or when rTMS of either PC was delivered 2 s after the presentation of the undegraded image. In a control experiment aiming to investigate whether the effect of rTMS of the right PC was related to the semantic nature of the visual stimuli, we found that delayed identification of degraded pictures was affected to the same extent when images representing animals or faces were used. Conclusions: Findings strongly support the hypothesis that both PC at the level of the intraparietal sulcus play a pivotal role in the Eureka effect particularly in consolidation processes. This involvement was likely supracategorial. Data contribute to elucidate the neural network underlying rapid perceptual learning.
Clinical Neurophysiology