Some characteristics of the information processing paradigm are discussed. Characteristics of fast process research are particularly emphasized. Fast process research deals with elementary information processes, called ‘mechanics’. These processes cannot be revealed by introspective methods, but only by chronometric studies. Attentional research has revealed automatic and controlled mechanics. Only the latter require attention resources for their execution. The functional state of the brain is thought to affect in particular the efficiency of controlled mechanics. Methods used in fast process research and cognitive psychophysiology could be helpful in deciding if behavioural disturbances result from limitations in the nature of the mechanics or in their efficiency.