This article presents a reflection about the different types of phenomenological properties of mental states, also known as qualia. With the objective of identifying the role of qualia in cognition, the qualitative nature of phenomenology is discussed. It is proposed that knowing is a process by which new forms are given to experience through the progressive elucidation of its qualitative properties. Second, the characteristics of two different types of qualia and their roles in cognition are analyzed. A first type, with intrinsically cognitive characteristics, is associated with emotions and other similar states that participate as a center of thought, as a result of their accessibility to self-consciousness. A second type, consisting of perceptual qualia or sensations, corresponds to consciously inaccessible phenomena, and thus plays a representational role that does not depend on its specific qualitative characteristics.