I think all cognitive psychologists should know about the major ape language studies, including work with Washoe, Nim, Chantek, Sarah, Lana, Sherman & Austin, Kanzi, Ai, Panzee and Panbanisha, Alex, Ake, and others. Cognitive psychology in all its topic areas is intimately tied to language, and how we process linguistic information. This includes communication theory, and many other areas. Thus, a fully informed cognitive psychology must include knowledge of what we know about what nonhuman animals can (and cannot) do by way of learning aspects of human language. I would include also in this a broader understanding of basic animal communication systems, because those also involve cognitive processes shared with humans in some ways (e.g., perception, classification, discrimination, etc.). In addition, these animals studies describe how one can use the abilities of special animals to ask unique questions about the role of language in other cognitive processes.