Let me start with an observation. Some forty years ago linguistics played a central role in cognitive science. For instance, the well-known report of the Sloan Foundation on Cognitive Science (1978) argued that the major fields contributing to the newly established area of cognitive science included philosophy, psychology, computer science, anthropology, neuroscience and linguistics. In answering the question what cognitive science stands for, the report presents language as the prime example of a cognitive system (“What is a cognitive system? This report concentrates on language as a prime example.”; Sloan Foundation report, p. viii). In that era, linguistics was seen as a key player in cognitive science. Although today language is still an important topic at cognitive science and cognitive neuroscience meetings, studies on language-relevant topics are no longer strongly influenced by the developments in linguistics. I consider this to be an unfortunate situation. For one, currently many studies on language in cognitive neuroscience could profit from more linguistic sophistication. Second, linguists could help cognitive (neuro)scientists to be more advanced in their thinking about representational structures in the human mind. Even if these structures are not necessarily linguaform in nature, linguists have built up a lot of expertise in thinking about representational issues that could be tremendously useful for other fields of cognitive (neuro)science.
In the remainder I will first present my diagnosis: why did linguistics get marginalized in cognitive science? Then I will give some suggestions for improvement.
Part of the diagnosis is related to changes in our views on the nature of the human mind. Some fourty years ago the commonly held belief was that the relevant mental representations are propositional or linguaform in character. Hence, studying linguistic structures was vital for our understanding of the human mind. This is, however, no longer the prevailing view. Representations are these days often seen as “high-dimensional geometric manifolds. They are maps.” (Paul Churchland, Plato’s Camera, 2012). Language-like structures do not embody the basic machinery of cognition. “the human neuronal machinery differs from that of other animals in various small degrees, but not in fundamental kind.” (Churchland). An example of this thought-transition is the so-called imagery debate. Influential cognitive scientists (e.g. Stephen Kosslyn), have argued that visual mental imagery is an internal, visual experience. On this account visual mental images are structurally analogous to visual representations, and are caused, at least in part, by psychological processes shared with the visual system. Others (e.g., Zenon Pylyshyn), argue that all thoughts, including mental images, are propositional. Based on many empirical studies on mental imagery, the conclusion is that Kosslyn’s position is strongly supported, at the expense of a propositional view on mental imagery. In short, the idea that the language of thought consists mainly of mental objects with a sentence-like structure is no longer the prevailing view in cognitive (neuro)science.
The other component of the diagnosis is related to developments internal to the field of linguistics. The field of linguistics as a whole has become internally oriented, partly due to the wars between different linguistic schools. With exceptions, linguists have turned their backs to the developments in cognitive (neuro)science, and alienated themselves from what is going on in adjacent fields of research. The huge walls around the different linguistic schools have prevented the creation of a common body of knowledge that the outside world can recognize as the shared space of problems and insights of the field of linguistics as a whole. When even at major linguistics conferences the program contains presentation such as “A short tour through the minefield of linguistic terminology” (SLE, 2014), one should realize that this state of affairs is a serious threat to the influence that linguists exert on the research agenda of cognitive science broadly. In the absence of an agreed-upon taxonomy of the central linguistic phenomena it will be nearly impossible for a researcher from another research field to relate to, or exploit linguistic knowledge successfully. Compare this to a related domain in cognitive science: memory research. Although there are different theories on memory, there is substantial agreement among memory researchers about the basic memory taxonomy (e.g. procedural memory, semantic memory, episodic memory) and the phenomena that are covered by this taxonomy. A similar situation is strongly needed in linguistics. The major linguistic societies could do us a great favour if they would be able to organize a coherent taxonomy of the central linguistic phenomena.
Another reason why linguistics has lost some of its credibility in its scientific Umwelt is due to disagreement about the methodological standards that one should adhere to. It is not universally accepted among linguists, in contrast to researchers in most other fields of cognitive (neuro)science, that in linguistics the same quantitative standards (including the proper statistics) should be adhered to as in the rest of cognitive science. For instance, Gibson’s and Federenko’s 2010 paper in TICS “Weak quantitative standards in linguistics research” triggered a host of often unfriendly replies from linguists. One of the counterarguments that I read went as follows: “When linguists evaluate contrasts between two (or more) sentence types, they normally run several different examples in their heads, they look for potential confounds, and consult other colleagues (and sometimes naive participants), who evaluate the sentence types in the same fashion. The fact that this whole set of procedures (aka, experiments) is conducted informally does not mean it is not conducted carefully and systematically.” Running sentences in your head and consulting a colleague is fine for discovering interesting phenomena and possible explanations (for the context of discovery anything goes), but it does not suffice as the context of justification. We are all open to confirmation bias. The fallability of introspection is equally well-known; it is a method that hence has fallen out grace in psychology a long time ago. Thus, to justify one’s theory, empirical data have to be acquired and analysed according to the quantitative standards of the other fields of cognitive science. In many circumstance, claims by an expert linguist of the form “sentence A is grammatical and sentence B is ungrammatical” will not suffice as a valid empirical data point in support of a specific linguistic theory.
The remedy: How could linguistics increase its impact and visibility within cognitive (neuro)science? Here are some tentative suggestions:
(i) Exploit the current availability of large corpora, and new analytical tools (e.g. graph theorical network analysis; analysis tools from evolutionary biology) to investigate the structure of linguistic knowledge. The increasing availability of large corpora puts linguists in a historically unprecedented position. It is nowadays possible to use quantitative tools effectively to characterize linguistic phenomena in a way that is more representative of their distribution in the communities of language users than could be done before (see the contribution of Martin Haspelmath for similar arguments: http://dic.hypotheses.org/754)
(ii) Do proper experimental research (including the use of inferential statistics) according to the quality standards in the rest of cognitive science. For the branches of linguistics in which it is claimed that linguistics contributes to understanding a central mental faculty of the human mind, linguists should exploit the full range of experimental tools to investigate language as a mental phenomenon (in addition to its cultural, sociological and historical characteristics). One should not expect that linguists will be experts in all the experimental methods currently available. But as in many other branches of cognitive science, it should come from interdisciplinary collaborations in which linguists should engage themselves to a much larger extent than currently is the case.
(iii) Embed linguistic theory in a broader framework of human communication (inclusion of gesture, dialogue, sociolinguistic variation, etcetera). Students of linguistics today are used to the fact that communication is inherently multimodal in nature. A well-known computational linguist in the Netherlands told me recently that it gets harder and harder to attract students to classical courses in linguistics, since analyzing sentences in isolation from their multimodal environment is deviating from the modern ways in which the younger generation is used to exert their language skills.
(iv) Maximize interdisciplinary contributions in a cognitive (neuro)science environment. The history of linguistics shows that it has had some of its most fruitful periods when it was embedded in a multidisciplinary enterprise. An example in case is the era of information science during the war and shortly thereafter (cf Levelt, “The history of psycholinguistics: the pre-Chomskyan era”, 2012). Often this also goes together with a more favourable funding situation for linguistic research.
(v) Provide language-specific information (instead of mostly top-heavy theory), which is the unique selling point of linguistics.
In my experience many of the recommendations that I made above are already taken on board by the younger generation of linguists. I am therefore optimistic about the prospects of linguistics as, once again, a central domain of scholarship in all of cognitive (neuro)science.