 Some advocates of the biased competition view emphasize the particular importance of the top-down biasing signals that the theory postulates (e.g., Beck and Kastner, 2009, p. 1156), taking the source of these signals to be the true locus of attentional selection. Others suggest that the biased competition theory is better understood as a theory that refuses to identify any such locus, and that it should instead be read (as suggested in Duncan’s original presentation of the theory, (Duncan 1996)) as attributing the selectivity of attention to the totality of an integrated competition, involving processes of various sorts at various levels, any part of which can bias any other (Mole, 2011, §6.7, 2015).