Table of contents

1. Introduction _____________________________________________________________ 2

2. Dictionary vs. Mental Lexicon_______________________________________________ 2

2.1. The frequency effect_________________________________________________________ 4

3. Words __________________________________________________________________ 5

3.1. What is a word? ____________________________________________________________ 5

3.2. Do words have a fixed meaning?_______________________________________________ 6

3.3. The prototype theory ________________________________________________________ 7

3.4. Sense relations______________________________________________________________ 9

3.4.1 Synonymy ______________________________________________________________________ 9

3.4.2. Antonymy______________________________________________________________________ 9

3.4.3. Hyponymy ____________________________________________________________________ 10

3.4.4. Meronymy ____________________________________________________________________ 11

3.4.5. Collocations ___________________________________________________________________ 11

3.4.6. Word-webs and atomic globules ___________________________________________________ 11

4. Lexical Processing _______________________________________________________ 12

4.1. Serial-autonomous models (Forster′s search model 1976) _________________________ 12

4.2. Parallel-interactive models __________________________________________________ 14

4.2.1. Morton′s logogen model (1969) ____________________________________________________ 14

4.2.2. Marslen-Wilson′s cohort model (1978) ______________________________________________ 15

4.3. Serial-autonomous vs. parallel-interactive processing models______________________ 16

5. Lexicon acquisition ______________________________________________________ 17

5.1. Children acquire words _____________________________________________________ 17

5.1.1. The vocabulary spurt ____________________________________________________________ 17

5.1.2. Over- and underextensions________________________________________________________ 18

5.2. Constraints on word meaning ________________________________________________ 19

5.2.1. The taxonomic assumption________________________________________________________ 19

5.2.2. The whole object assumption ______________________________________________________ 20

5.2.3. The mutual exclusivity assumption _________________________________________________ 20

6. Conclusion _____________________________________________________________ 21

7. References______________________________________________________________ 23

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1. Introduction

Every speaker of a language has a mental lexicon which stores every word the speaker knows. The

mental lexicon has huge capacities (translated from Rothweiler 2001:21). Adults usually

underestimate the size of their vocabulary. Aitchison (2003:6) refers to a study by Seashore and

Eckerson (1940) in which they estimated that an educated adult knows more than 58,000 common

′basic words′, 1,700 rare ′basic words′ and 96,000 derivates and compounds. This is an overall total of

150,000 words of which 90% are used actively. Aitchison (2003:6-7) argues that "this figure is

controversial, because of the problems of defining ′word′ and the difficulty of finding a reliable

procedure for assessing vocabulary knowledge". Rothweiler (2001:21) refers to Miller (1993) who

estimates the vocabulary of an average educated adult at 80,000 words.

Rothweiler (2001:21) argues that the mental lexicon is more than a passive memory. She refers to

Levelt (1989:181) that the lexicon is a central station between conceptualization on the one hand and

the grammatical and phonological coding of language on the other hand. Both the acquisition of words

and the usage of words refer to lexical processes.

The lexicon seems to be well structured because words can be located in a split second (Aitchison

2003:7). Both Rothweiler and Aitchison refer to confirmed experiments that native speakers can

recognize a word of their mother tongue in 200 ms or less from its onset and can reject a non-word

sound sequence in about half a second. Production of a word is slightly slower: the lexicon is able to

generate up to six syllables a second, "making three or more words [...] fairly standard" (Aitchison

2003:8). Errors of selection are rare ­ one in about a thousand words.

This paper is about the mental lexicon. First, I will compare the mental lexicon to a dictionary and

come to the conclusion that it differs radically from a dictionary in terms of organization and content.

Second, I will focus on ′words′, what they are and whether they have a fixed meaning. I will outline

Rosch′s prototype theory and sense relations. Third, I will come to lexical processing and describe two

processing models: the serial-autonomous models and the parallel-interactive models. My last chapter

will be an overview on early language acquisition and constraints on word meaning.

2. Dictionary vs. Mental Lexicon

The hypothesis is "that there is [...] little similarity between words in our minds and words in book

dictionaries" (Aitchison 2003:10).

Language is a communication system employing arbitrary symbols. These symbols,

normally words, have to be stored. [...] [Different] techniques of storage are available:

words can be listed in a reference book, [...] or they can be kept in the mind. [...] Word-

stores that are primarily consulted for the reason of information retrieval are referred to as

dictionaries

. By contrast, word-stores that constitute a component within a natural

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language processing system are called

lexica

. [...] The most common types of book

dictionaries are encyclopedic, monolingual dictionaries, bilingual dictionaries, or

dictionaries for special purposes such as synonym dictionaries, foreign word dictionaries,

etc. [...] A lexicon, by contrast, is the central module of a natural language processing

system [...]. It closely interacts with the other components of the language processor and

provides detailed information about the words to be produced or comprehended. (Handke

1995:49-50).

Dictionaries and the mental lexicon do not only differ, they also have one thing in common: "They

contain a large number of items which are defined linguistically" (Handke 1995: 50). This similarity

is, however, the only one. The mental lexicon differs radically from a dictionary. Dictionaries contain

words in alphabetical order. Aitchison (2003:10) argues that one could guess that the mental lexicon

might be organized in alphabetical order as well, since a person who can read and write spends a lot of

time "looking things up alphabetically". But the mental lexicon is not organized in alphabetical order,

which can easily be tested by looking at mistakes people make when they are "selecting one word in

error for another" (

ibid.

)

In error for the word ′guitar′ one might expect someone to accidentally pick

guinea

or

guipure

or

guise

[...] all words which are near neighbors in

NODE

(

The New Oxford
Dictionary of English

). (Aitchison 2003:11)

But this does not seem to be the case as

mistakes of this type are quite unlikely, as [it] becomes clear when we look at a few ′slips

of the tongue′. such as ′He told a funny antidote′, with

antidote

instead of ′anecdote′.

(

ibid.

)

These errors might hint at the fact that the mental lexicon might be "partially organized in terms of

initial sounds" (

ibid.

) but definitely not in alphabetical order. Other hints towards the mental lexicon′s

phonological organization are sound structures, stress patterns, sound associations, etc. As the mental

lexicon does not only concern spoken language, graphology has to be considered as well. Handke

(1995:70) refers to McKay′s (1970) so-called

tip-of-the-tongue phenomena

(see also Aitchison

2003:24). One might know the first consonant or the number of syllables of a word one is looking for,

but it cannot be retrieved from the lexicon as bits seem to be missing. Another way to organize the

mental lexicon are sense relations. If one cannot come up with a word but knows how the item looks

like, one could utter that it has to be something similar to... .

Generally speaking entries in a dictionary include access unit (stem or graphological structure),

phonological specification, grammatical aspects (morphology and syntax), meaning, further aspects,

e.g. history, examples in context, alternative spellings (depending on dictionary type) (see Handke

1995:62). Entries in the lexicon need to be specified for aspects of phonology, graphology,

morphology, syntax and semantics (Handke 1995:68).

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So far, the organization of both dictionary and mental lexicon has been dealt with, but the content

differs as well. A book dictionary contains a fixed countable number of words. "Book dictionaries are

therefore inescapably outdated, because language is constantly changing, and vocabulary fastest of all"

(Aitchison 2003:11). Book dictionaries are therefore somewhat limited. "They contain a relatively

small amount of information about each item" (Aitchison 2003:15). The knowledge per entry in the

mental lexicon would let any dictionary burst:

spelling:

articulation

[′teibl]

idioms:

t a b l e

to do sth. under the table

to turn the tables on sb.

meaning: piece of furniture

to lay sth. on the table

with legs and horizontal

top to put things on

semantic field:

chair, cupboard,

hyponyms:

bed

dining table

coffee table

frequency:

table

high

hyperonym:

furniture

style level:

neutral

derivations:

...

could not find

compounds:

inflexion:

any

dining table, table

plural -s

cloth, table manners,

table tennis

The mental lexicon offers more knowledge per entry (as seen above) and does not contain a fixed

number of words compared to book dictionaries. It is also far more productive, new words can be

added instantly, we are able to form rhymes once we heard a word and coming back to the

introduction we can reject a non-word sound sequence of our mother tongue within half a second.

Looking through a book dictionary for such a non-word would take much longer although with the

help of computers access is a lot easier.

2.1. The frequency effect

"It is a well-known observation that high-frequency words are processed faster" (Bonin 2004:xi).

"Frequent words are easier to get at than infrequent words" (Handke 1995:267). Searching for a word

in a book dictionary which one has never heard before does not take any longer than searching for a

word which one has come across many times. The frequency effect argues that high-frequency words

are found quicker in the mental lexicon because they are stored in many different areas, i.e. high-

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frequency words are represented more than once in the brain. A book dictionary organized in such a

way that more frequent words appear at the beginning whereas less frequent words have to move

towards the end would be rather useless. Because who would define which words to place where?

People would have to search the whole dictionary in order to find the word they are looking for.

Last but not least, (translated from Quetz (1998:273) quoting Koll-Stobbe (1994:56)): looking for a

word in a dictionary is a conscious activity whereas the usage of the mental lexicon is not. It is

something like a system which we activate automatically when we are speaking or reading. Only when

we are facing a problem, e.g. we come across a word we do not know or we want to say something but

it is on the tip of our tongue, will our attention be drawn towards this aspect of speech processing.

The mental lexicon offers such a vast variety of aspects that it cannot only be regarded as a lexicon but

as storage in multiple ways: As a library, a computer memory, an attic, a pigeon loft or even a treasure

chest.

3. Words

3.1. What is a word?

What does the mental lexicon contain? Words. What is a word? Intuitively, everybody

seems to know what it is, but it has been extremely difficult to provide a

comprehensive definition of a word. (Piasecka 2001:7)

So what exactly is a word? People are able to intuitively isolate words from sentences. The same goes

for children, even if they are too young to have a concept of metalanguage (translated from Rothweiler

2001:28). Piasecka (2001:7) argues that "there is no single, universal definition of a word". Linguists

do not have one definition because a phonetician will give a different definition than a morphologist.

A phonetician is interested in spoken discourse, so for him a word in isolation consists of

one or more phonemes and is characterized by stress. When individual words are

combined into an utterance, stress of the words carrying meaning is kept, but the so-

called grammatical words may lose their stress and become unstressed (

ibid.

)

A word on the morphological level is an independent unit. Because sentences are made out of words it

is necessary that words are isolable, movable and replaceable (translated from Rothweiler 2001:29).

In written discourse a word is defined in terms of orthography [...] ′a word is any

sequence of letters [...] bounded on either side by a space or a punctuation mark

(Piasecka 2001:7-8).

We might think of words as separate items as the concept of a word in the Western world is influenced

by written language: written words can be easily perceived and counted. But words in a spoken

language appear rather as a string of sounds than separate items. Spoken words can be isolated by

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