Mental Lexicon (Psycholinguistics)

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In psycholinguistics, a person's internalized knowledge of the properties of words. Also known as a mental dictionary.

There are various definitions of mental lexicon. In their book The Mental Lexicon: Core Perspectives (2008), Gonia Jarema and Gary Libben "attempt" this definition: "The mental lexicon is the cognitive system that constitutes the capacity for conscious and unconscious lexical activity."

The term mental lexicon was introduced by R.C. Oldfield in the article "Things, Words and the Brain" (Quarterly Journal of Experimental Psychology, v. 18, 1966).

Examples and Observations

  • "The fact that a speaker can mentally find the word that he/she wants in less than 200 milliseconds, and in certain cases, even before it is heard, is proof that the mental lexicon is ordered in such a way as to facilitate access and retrieval."
    (Pamela B. Faber and Ricardo Mairal Usón, Constructing a Lexicon of English Verbs. Walter de Gruyter, 1999)
     
  • The Dictionary Metaphor
    - "What is this mental dictionary, or lexicon, like? We can conceive of it as similar to a printed dictionary, that is, as consisting of pairings of meanings with sound representations. A printed dictionary has listed at each entry a pronunciation of the word and its definition in terms of other words. In a similar fashion, the mental lexicon must represent at least some aspects of the meaning of the word, although surely not in the same way as does a printed dictionary; likewise, it must include information about the pronunciation of the word although, again, probably not in the same form as an ordinary dictionary."
    (D. Fay and A. Cutler, "Malapropisms and the Structure of the Mental Lexicon." Linguistic Inquiry, 1977)

    - "The human word-store is often referred to as the 'mental dictionary' or, perhaps more commonly, as the mental lexicon, to use the Greek word for 'dictionary.' There is, however, relatively little similarity between the words in our minds and the words in book dictionaries, even though the information will sometimes overlap. . . .

    "[E]ven if the mental lexicon turns out to be partially organised in terms of initial sounds, the order will certainly not be straightforwardly alphabetical. Other aspects of the word's sound structure, such as its ending, its stress pattern and the stressed vowel, are all likely to play a role in the arrangement of words in the mind. 

    "Furthermore, consider a speech error such as 'The inhabitants of the car were unhurt.' where the speaker presumably meant to say passengers rather than 'inhabitants.' Such mistakes show that, unlike book dictionaries, human mental dictionaries cannot be organized solely on the basis of sounds or spelling. Meaning must be taken into consideration as well, since humans fairly often confuse words with similar meanings, as in 'Please hand me the tin-opener' when the speaker wants to crack a nut, so must have meant 'nut-crackers.'"
    (Jean Aitchison, Words in the Mind: An Introduction to the Mental Lexicon. Wiley-Blackwell, 2003)  
  • An Australian's Mental Lexicon
    "Even with hard yakka, you've got Buckley's of understanding this dinkum English sentence, unless you're an Aussie.

    "An Australian has no difficulty understanding the above sentence, while other English speakers might struggle. The words 'yakka,' 'Buckley's,' and 'dinkum' are in the vocabulary of most Australians, that is, they are stored as entries in the mental lexicon, and therefore an Australian has access to the meanings of these words and can consequently comprehend the sentence. If one possessed no mental lexicon, communication through language would be precluded."
    (Marcus Taft, Reading and the Mental Lexicon. Psychology Press, 1991)