Polarization has become a hot topic following the growth of inter-group animosity and the importance of identity in politics and society, rendering dialogue and democratic consensus difficult. In contrast, the neurophysiological and developmental underpinnings of partisan bias are still relatively unknown. Since Electroencephalography (EEG) allows high temporal resolution measurements of brain activity in response to political stimuli (Event-Related Potentials - ERPs), this Project (part of the IP-PAD project and funded by European Commision) has set its sights on detecting early neuromarkers of partisan bias and discussing how the conditioning may develop. Research in the fields of group dynamics and social prejudice indicate seminal paths of inquiry. For this purpose, survey measures of partisanship strength are expected to accompany levels of intergroup bias in neuronal processing of political media, as measured by ERP amplitude, following the presentation of poster-like images of political leaders and partisans. Meanwhile, self-reported measures of cognitive openness and empathy will both be used along neurophysiological experiments, as to predict reduced intergroup bias, and with developing populations, drawing possible causal relationships for future research and the implications of political communication.