Abstract: This article deals with the processing of subject and object WH-sentences of Brazilian Portuguese (BP). Specifically, it investigates the subject/object asymmetry in this type of sentence, following previous results using self-paced reading technique (OLIVEIRA; MAIA, 2010; OLIVEIRA, 2013). Eyetracking and electroencephalography (EEG) techniques were used as diagnostic tools for real-time linguistic processing. The goal was to find evidence of the modus operandi of the parser during the processing of subject and object syntactic functions in Brazilian Portuguese WH-sentences and verify if there are discrepancies between the techniques. The results allow discerning the levels of representational, algorithmic and implementation analysis, in the direction of the classical proposal of Marr (1982).