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The results from the current cross-modal lexical decision task could clarify the

controversial issue of lexical ambiguity resolution (modular/interactive hypothesis) as

well as the internal organization of mental lexicon (single/separate representation) for

polysemy. First of all, it was found that homonymy and polysemy behaved differently

on meaning activation during the sentence resolution of lexical ambiguity. Only the

contextually appropriate meaning was activated in the case of homonymous words

(words with unrelated meanings), whereas in the case of polysemous words (words

with interrelated senses), both contextually relevant and irrelevant meanings were

activated. In other words, while the resolution of homonymous meanings in sentence

processing depended on the contextual information, polysemous meanings were

resolved and processed regardless of the context effect. These results suggest that two

types of ambiguity are resolved differently in sentences and that the distinction

between different types of ambiguity (in terms of meaning relatedness) is of

importance in the issue of lexical ambiguity resolution. As we have discussed in

Chapter 2, previous research has not come to an agreement regarding whether or not

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the context has an immediate effect on the resolution of lexical ambiguity. When

examining the ambiguity during sentence comprehension, most of the previous

studies in fact centered on only homonyms, or they used polysemous words

interchangeably with homographs or homophones in their experiments. However,

finding that homonymy and polysemy have different patterns during sentence

resolution, our study proposes that the distinction between different types of lexical

ambiguity which different on their meaning relatedness should not be ignored and the

effect of sense relatedness of ambiguity would be a potential factor to influence the

experimental results in lexical ambiguity resolution. To further find out how previous

research, which did not make a distinction between homonymy and polysemy, is

different from ours, a more specific comparison was made. We compared our study

with some of the previous studies on lexical ambiguity resolution whose experimental

designs were similar to the present study, i.e., by using cross-modal lexical decision

tasks with the settings adjusted to detect the immediate stage of processing. These

selected studies consisted of Swinney (1979), Onifer & Swinney (1981), and Ahrens

(1998, 2001, 2002, 2006), in all of which the results supported the modularity

(context-independent) view or the multiple access model (see Table 6.1).

Table 6.1. Comparison of the previous and present cross-modal lexical decision tasks

(English) Not distinguished (H: 58%, P:42%)

As shown in Table 6.1, first of all, the major difference between previous studies

and the current research is the distinction between homonymous words and

polysemous words. For example, we collected the available materials from Onifer and

Swinney (1981) and Ahrens (2001, 2006) and calculated their distribution of different

types of ambiguity, for which the homonymy/polysemy distinction was depended on

whether two meanings of ambiguity were listed as different entries or the same entry

in the dictionary (based on The American Heritage Dictionary of the English

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distribution of homonymy/polysemy in these studies was not consistent and not

specifically controlled; for instance, Onifer and Swinney (1981) included both

homophones such as flower/flour and polysemous words such as cold (which means

“low temperature” or “flu”) in their experiments but did not make a distinction, and

Ahrens (2001) also included both homonymous word such as bei4shu1 (背書) (which

means “to memorize” or “to endorse”) and polysemous words with metaphorical

extension such as zou3hou4men2 (走後門) (which means “to take illegal advantage

of” or “to get in by the back door”) in her experiment. Different from the results the

above mentioned studies have found, our study here (which distinguishes between

different types of ambiguity) does not provide strong evidence for the

context-independent view (multiple access model), as the resolution of homonymous

words is found sensitive to the context. Therefore, our study suggests that meaning

relatedness of lexical ambiguity would be a crucial factor to influence the results on

lexical ambiguity resolution.

Second, the effect of meaning dominance (frequency distribution) was not

examined in Swinney (1979) and Ahrens (1998, 2001, 2002, 2006), in which

equi-biased ambiguity (i.e., two meanings of ambiguity were equally frequent) was

used. In Onifer & Swinney (1981), on the other hand, unbalanced ambiguity (i.e., two

meanings of ambiguity were unequally frequent) was employed and their results

found multiple access of meanings and thus argued against frequency effect, for both

the dominant and subordinate meaning were activated. If there was a strong effect of

meaning frequency, on the other hand, the less dominant meaning should not be

activated as the more dominant meaning was. Therefore, they suggested that

differences on meaning dominance did not influence the activation of multiple

meanings on lexical ambiguity resolution. However, in the present study, unbalanced

ambiguity was also used and the results found a potential frequency effect for

homonymy, in which only the dominant meaning (also the contextually appropriate

meaning) was activated, but not for the case of polysemy, in which both the dominant

and subordinate meanings were accessed. In other words, unbalance on meaning

distribution of ambiguity only had influence on homonymous meanings but not on

polysemous meanings. The different patterns again not only lay emphasis on the

difference between homonymy and polysemy but also indicate the influence of sense

relatedness. For homonymy, its unrelated meanings might be separately and distinctly

represented, and when there are two incompatible meanings to be resolved and

processed in context, meaning frequency may come into play to help pick out one

meaning for further processing. Therefore, the more dominant one would have greater

possibility to be accessed, and the less dominant meaning may not be able to

overcome the effect of meaning dominance and hence would be suppressed. For

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polysemy, on the other hand, multiple meanings are interrelated, and there may be no

immediate need for the meaning frequency effect to act in order to choose one of

those compatible meanings. Consequently, both the more dominant meaning and the

less dominant meaning of polysemy could be initially accessed. Although so far the

experiment in the present study cannot make a clear distinction as to whether the

context itself or both context and frequency have effects on the first meaning

activation of homonymy, since its contextually appropriate meaning is also the more

dominant meaning in our experiment, the current research however does illustrate that

homonymy and polysemy have different processing patterns on lexical access and

therefore points out the important effect of meaning relatedness.

Overall, concerning the controversial issue in lexical ambiguity resolution, our

study suggests that whether the context-independent model or the context-dependent

model holds right should depend on which type of ambiguity is considered. We would

take the position that absolute modularity and absolute interaction in lexical

processing can be considered as the two extremes along a continuum, which is close

to the view taken by Tanenhaus, Dell, and Carlson (1987) reconciling modular and

interactive models (see also Simpson & Krueger, 1991; Tabossi, 1988). Different

factors, such as meaning relatedness of lexical ambiguity, may influence the degree of

activation along this continuum. For the issue of lexical ambiguity resolution, as we

have outlined in Chapter 2, two major effects—context and meaning frequency—have

been pointed out in previous research and four models in relation to these two factors

have been proposed. For ease of reference, we reduplicate Table 2.3 in Chapter 2 as

Table 6.2.

Table 6.2. Different types of models of lexical ambiguity resolution (reduplicated) Processing

hypotheses

Language processing

models Types of models

Context effect

(at an early stage)

consideration when dealing with the issue of lexical ambiguity resolution— the sense

relatedness of ambiguity itself. Therefore, as Figure 6.1 shows, the two factors,

context and frequency, in relation to sense relatedness, would influence the degree of

meaning activation in lexical ambiguity resolution. On the one hand, whether the

context effect occurs or not is relevant to the effect of sense relatedness, since it was

found that ambiguous meanings with low relatedness showed context effect in

sentence processing but not for ambiguous meanings with high relatedness. On the

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other hand, whether the frequency effect occurs or not is also relevant to the effect of

sense relatedness, for meaning dominance only had influence on ambiguous words

with unrelated meanings, but not on words with closely related meanings. Therefore,

it is suggested that the examination of the context and frequency effect in lexical

ambiguity resolution should not be separate from the consideration of the sense

relatedness effect.

Figure 6.1. Context and frequency effect in relation to the effect of sense relatedness

on lexical ambiguity resolution.