Linguistics is a part of the field of cognitive science. The hypotheses that we have developed in this book about important linguistic elements, like phonemes, morphemes, phrase structure etc. are in some sense really hypotheses about how the human mind represents language. A classical view of cognitive science holds that the mind has symbolic representations, and operations that transform these representations. Connecting this larger framework to linguistics, we can think of our mental grammars as the means by which linguistic representations (like our phonemes, morphemes etc.) are transformed. For example in spoken languages, a phoneme is encoded into the appropriate phone according to the phonological rules of the language prior to being spoken.
Sometimes, the intuitions of native speakers provide enough evidence for the importance of a particular linguistic element or rule as a part of the mind’s capacity for language. But sometimes linguists are interested in different kinds of evidence for these important concepts in linguistics, or they want to know how the important concepts are deployed during language production or comprehension. Psycholinguistics is an interdisciplinary field in which researchers devise experiments to test hypotheses about linguistic representations and processes in the human mind. Psycholinguists normally use behavioural methods, for example measuring how quickly someone can make a decision about a word after seeing it on a computer screen (we will explore this particular method later in the chapter). In this chapter we will focus on the relationship between psycholinguistic findings and linguistic theory, but psycholinguists also propose and evaluate theories of mental processes like language production and comprehension.
As a basic assumption, we will assume that the human mind has a biological basis in the brain. Neurolinguists conduct similar research to psycholinguists, but with a focus on figuring out how language as a cognitive system is organized and implemented in the biology of the human brain. They use experimental methods from cognitive neuroscience as well as examining disorders of language that arise from problems in the brain, for example following a stroke or other brain injury. Neurolinguists may be interested in evaluating linguistic theory, but also have neurolinguistic theories in their own right, similar to psycholinguists.
The fields of psycholinguistics and neurolinguistics are too vast to be summarized in one chapter of one book. So in this chapter, we will focus on experiments that provide further evidence for some of the important concepts from earlier chapters. We will also highlight some of the key experimental methods used in these fields.