Influences of perinatal dioxin load to visual motion and oddball stimuli examined with an EEG and MEG analysis

Objective With MEG and EEG the effect of perinatal dioxin load of 38 healthy 7- to 12-year-old children was studied to assess possible disturbances of visual development. Methods Latencies and amplitudes of the motion (N2 with subcomponents) and oddball responses (N200 and P3b) were analysed after age correction. Results With increasing load, latencies increased and the amplitudes of the oddball components tended to be reduced. The latency increase between the high- and low-loaded children was about 13 ms (P < 0.004) and the oddball response showed an amplitude decrease of 12% (P = 0.009). Conclusions It may be concluded that, during the end-80s/early-90s, exposure to background levels in industrialized regions seems to have resulted in small underdevelopment or damage to visual motion processing and visual cognition. Significance Since dioxin pollution by incinerators still exists in many regions in developing countries and also still, although at a smaller scale, in the industrialized world, perinatal loads of similar magnitude and possibly more as measured in this study may occur and as a consequence might affect the developing brain.