Abstract

Higher-order representation (HOR) theories posit that the contents of lower-order brain states enter consciousness when tracked by a higher-order brain state. The nature of higher-order monitoring was examined in light of current scientific knowledge, primarily in experimental perceptual psychology. The most plausible candidate for higher-order state was found to be conceptual short-term memory (CSTM), a buffer memory intimately connected with a semantic engine operating in the medium of the language of thought (LOT). This combination meets many of the requirements of HOR theories, although falling short in some significant respects, most notably the inability of higher- order states to represent more than a small fraction of the information contained in primary states, especially in vision. A possible way round this obstacle is suggested, involving the representation of visual detail by means of ensemble concepts.