One of the objects of consciousness research is the attention, which has the property of inhibitingirrelevant information and emphasizing the processing of relevant information. It has been proposed thatclaustrum (CLA) determines which information to direct selective attention to in a top-down manner. Amodel in which the CLA regulates attentional selection from higher-order regions to sensory regions wasproposed. The CLA-mediated neuronal connections can be assumed to be a counter stream structure, butreciprocal connections between the CLA and cortical and higher order regions have been identified. In thispaper, we discuss the mechanism of attentional selection