Psycholinguistics

Psycholinguistics LECTURE#15

Psycholinguistics • Language loss in the normal elderly (speakers of 70þ and 80þ with no apparent brain damage) varies considerably between individuals. • There is often a decline in the receptive skills. • Sentence length does not appear to be a major obstacle; but sentence complexity does. • The main reason would appear to be increased difficulty in co-ordinating syntactic and semantic processing. • This is especially noticeable when older people are called upon to process complex syntactic structures such as subordinate clauses. • Their recall of connective links between sentences may also be less precise than that of younger subjects.

Psycholinguistics • The variation between individuals may reflect the fact that some are more successful than others in developing strategies to compensate for the reduction in syntactic information. • They often appear to fall back upon context, using sentence meaning and world knowledge to supplement their understanding. • This reliance on semantics leads to difficulty in dealing with sentences which are ambiguous in meaning.

Psycholinguistics • Many aspects of higher-level comprehension appear unimpaired: • for example, the ability to make inferences, to integrate incoming knowledge into a mental representation and to bring world knowledge to bear. • But there may be a reduction in the number of factors which the older person’s working memory can handle: • Hence occasional difficulty in retaining the information necessary for handling pronoun reference or negative sentences.

Psycholinguistics • Older people find it easier to recall sentences where the chronological order is the order of mention (After locking the door, she turned off the lights) than those where it is the reverse (Before locking the door, she turned off the lights). • So far as the production of speech is concerned, elderly speakers tend to produce more unfinished sentences than do younger ones, and appear to need more time to assemble their utterances. • One suggestion is that there is a general decline in a speaker’s ability to self-monitor, which causes problems with both production and comprehension.

Psycholinguistics • This may be attributable, again, to changes in working memory which reduce the ability to perform multiple tasks. • The classic syndrome reported by the elderly is difficulty in finding words: they report more frequent Tip of the Tongue experiences than do younger speakers. • However, they have a high success rate in finally locating the desired word, and there is no evidence that items are actually ‘lost’ from the lexicon.

Psycholinguistics • The chief change seems to be that the process of retrieving lexical items becomes slower, as does the process of making associative links between items. • The results are seen in unfinished sentences and a higher incidence of ‘general’ terms (flower for rose, walk for march etc.).

Psycholinguistics • There has been interest in a theory (the regression hypothesis) that language loss may replicate in reverse the order of acquisition by infants. • The hypothesis has not been demonstrated. • Though certain linguistic concepts involving space, quantity, temporal relations and subordination do appear to cause problems for some elderly speakers and listeners, there is no evidence of a systematic pattern of loss.

Psycholinguistics • AGNOSIA • A condition, sometimes caused by brain damage, where a patient receives a signal but cannot recognize or classify it. • They might see a familiar object but be unable to say what it is. • Visual agnosia in reading and auditory agnosia in listening result in an inability to perceive that two identical word forms represent the same word.

Psycholinguistics • AGRAMMATISM • Speech production in which many function words and inflectional endings are omitted – one possible symptom of the syndrome known as Broca’s aphasia. • Early studies of agrammatism associated it with damage to motor areas of the brain which prevented sufferers from assembling syntactic structures. • However, it was discovered that many Broca’s aphasics had problems in understanding function words as well as in using them. • A theory developed that there may be separate stores for closed class items (those with a grammatical function) and lexical items (those where meaning has to be accessed). • Agrammatism may derive, in part at least, from difficulty in accessing the former.

Psycholinguistics • AMBIGUITY: LEXICAL • Ambiguity at word level, as represented in a sentence such as Tick the right box. • Early experiments discovered that subjects’ reactions were slower immediately after reading an ambiguous word. • This suggested that the processing of ambiguous words demands additional attentional resources because two senses of the word are activated rather than just one.

Psycholinguistics • An important question is what happens when a potentially ambiguous word is disambiguated by the context in which it appears. • One view is that context influences the processing of the word, so that we only access the appropriate sense. • The other, which has rather more evidence to support it, is that we cannot help but activate both senses. • A much-quoted experiment (Swinney, 1979) indicated that hearing the word BUG triggered associations with both possible meanings (insect and spy gadget), even when the word occurred in transparent contexts.

Psycholinguistics • A second issue is whether all interpretations of an ambiguous word are treated equally. Compare, for example, a balanced homonym such as RIGHT, where both words are highly frequent, with a polarized one such as SCALE, where the dominant sense refers to a set of numbers but a secondary one refers to a characteristic of a fish. • Experiments have examined how readers process sentences where polarized homonyms are used in their secondary senses; they indicate that reading slows down even when there is a disambiguating context. • This suggests that multiple meanings of words are activated in parallel, with priority given to the dominant one.

Psycholinguistics • AMBIGUITY: SYNTACTIC • Syntactic ambiguity falls into two types: • local ambiguity where the word class or syntactic function of a word is unclear at the moment the word occurs, but is made clear by subsequent context. • Examples (slash indicates point of ambiguity): • The horse raced past the barn / fell. • John remembered the answer / was in the book.

Psycholinguistics • standing ambiguity where a sentence remains ambiguous even after it is complete. • In (e.g.) Bond saw the spy with the telescope, the telescope might be carried by either Bond or the spy, and the ambiguity can only be resolved by the wider context. • Local ambiguity provides insights into syntactic parsing because it enables the researcher to investigate how a subject reacts both at the point where the ambiguity occurs and at the point where disambiguation occurs.

Psycholinguistics • The reactions of a reader can be monitored by tracking eye movements or by presenting sentences word by word and noting when a processing difficulty causes a delay in moving on to the next word. • In principle, the language user could react to ambiguity in several ways: • a. Adopt a single analysis, even at the risk of later having to abandon it (a ‘garden path’ view). • b. Hold alternative analyses in parallel, but provisionally make use of the one that best fits the context and add it to the meaning representation.

Psycholinguistics • c. Hold alternative analyses in parallel, where they compete with each other until one becomes so highly activated on the basis of new evidence that it is accepted (a constraint-based approach). • d. Delay commitment until the ambiguity is resolved. • Evidence suggests that one preferred interpretation is chosen and revised later if necessary. • Eye-movement experiments show that readers experience processing difficulty not so much at the point where an ambiguity arises, but at the point where disambiguation occurs.

Psycholinguistics • This might appear to support a ‘single analysis’ view, but might equally reflect processes b or c. • An important issue is how the preferred interpretation is chosen. • Early discussion focused on syntactic considerations. • It was suggested that the listener/reader exercised a preference for a canonical (Subject–Verb–Object) sentence structure: hence an initial assumption that The horse raced... consists of Subject þ main verb.

Psycholinguistics • A more sophisticated theory proposed two strategies that are specifically syntactic: • Minimal attachment. Build the simplest structure consistent with the rules of the grammar. • Late closure. • Where there is a problem of attachment ambiguity make an attachment to the clause that is currently being processed; ideally, assume that the current clause is the main one.

Psycholinguistics • Later lexicalist accounts introduced a semantic element, suggesting that the preferred reading is based upon the argument structure of the current verb. • For example, the pattern associated with DONATE involves a donator and a recipient. • The preferred interpretation of the man donated would thus be: Agent þ Past Simple verb. • But animacy also plays a part. • A cheque cannot BE AN agent, so the preferred interpretation of the cheque donated would be: object donated þ past participle.

Psycholinguistics • A third explanation is entirely semantic. • The preferred continuation of: The lawyer examined . . . would be the witness rather than by the judge, simply because world knowledge tells us that lawyers tend to examine rather than be examined. • There is thus some disagreement as to whether we attempt to resolve ambiguity using purely syntactic criteria, or whether lexicosyntactic or semantic criteria play a part.

Psycholinguistics • A criticism of some of the ambiguity data is that it is not based upon a natural parsing situation. ‘Garden path’ sentences are often presented to subjects without any preceding context. • It is therefore not clear at what point context might normally have enabled the reader to resolve the kind of ambiguity that has been studied. • For example, the preferred interpretation of The horse raced past the barn . . . might be influenced by a preceding sentence which ran: There were two horses. • A referential theory argues that contextual information will often ensure disambiguation.

Psycholinguistics • ‘Garden path’ ambiguity is more easily exemplified in written texts than in spoken – though, it is sometimes dependent upon the omission of normal punctuation. • In speech, prosody provides important cues (intonation, pausing, shifts in pitch level, variations in articulation rate), which often serve to resolve attachment ambiguity by indicating where clauses begin and end.

Psycholinguistics • ANALOGY MODEL • A theory (Glushko, 1979) that English readers attribute pronunciations to unknown words by tracing analogies with known ones. • This is because the opaque nature of the English spelling system means that many words cannot be identified by using simple graphemephoneme correspondence (GPC) rules. • The most important area in a monosyllabic word appears to be the rime: the vowel plus final consonant(s). • Evidence for an analogy effect comes from experiments where readers find it harder to pronounce a non-word such as VINT which has neighbours of varying pronunciations (PINT and MINT) than one such as TADE whose neighbours all rhyme (FADE, MADE, WADE).

Psycholinguistics • Analogy is an important strategy in early reading. • However, the extent to which young readers make use of it (as against whole word matches) appears to vary between individuals and may partly reflect the method of instruction. • Furthermore, analogy cannot represent a complete alternative to GPC rules. • Many multi-syllabic words do not have neighbours; and there are many monosyllabic non-words such as JOOV whose pronunciation is easy to infer but which cannot be matched to similar words. • The analogy model has therefore been expanded to include parts of words: the pronunciation of JOOV might be determined by its resemblance to (GR)OOV(E).

Psycholinguistics • ANALYSIS • When a child is in the process of developing its first language or an adult is learning a foreign language naturalistically, much of the linguistic information that is acquired is unanalyzed. • Unanalyzed knowledge includes chunks of language: formulaic expressions and phonological sequences which have been picked up by the listener but have not been deconstructed into their constituent parts.

Psycholinguistics • In time, the constituents of these chunks are identified, and the child or language learner progresses towards more analyzed forms of knowledge. • Analyzed knowledge is more capable of being expressed (i.e. more explicit). • Operating in conjunction with analysis is a second parameter, control. • This refers to the extent to which a language learner has to apply attention when using the target language. • The degree of analysis and control exercised by the learner may be affected by the language task in hand.

Psycholinguistics • ANAPHOR RESOLUTION • An anaphor is a piece of language which refers back to a previously mentioned entity, action or idea. • Examples are: personal or demonstrative pronouns (she, that), pro-verbs (did so), adverbs (there) and expressions like the latter. • Anaphor resolution is the process that occurs when a listener or reader interprets an anaphor by linking it to its antecedent.

Psycholinguistics • Anaphor resolution appears to be an automatic on-line process, but one that can slow down reading – especially where there is uncertainty as to what the antecedent is. • Experiments using ambiguous anaphors provide insights into how an antecedent is chosen. • Factors include:

Psycholinguistics • Parallel position. • A pronoun in subject position is taken to refer to an antecedent that is in subject position. • Example: John phoned Bill. He said he was ill. • Current topic. • A pronoun is taken to refer to a topic that has been thematised in the preceding sentence or is in current focus. • Example: As for children, they don’t like them. Maybe they frighten them. • Proximity. • A pronoun is taken to refer back to the most recent noun phrase. • Example: He held some bread over the fire with a fork. It grew hot.

Psycholinguistics • Sometimes these criteria (e.g. parallel position and proximity) may be in conflict. • Further factors appear to be world knowledge, animacy and the thematic roles associated with a verb. • The first of these accounts for the different resolutions of they in: • a. They bought the apples because they were cheap. • b. They bought the apples because they were hungry.

Psycholinguistics • There has been much discussion of the kind of representation that an anaphor accesses. • This is especially an issue in listening, where there is no opportunity to look back to check understanding. • The listener has to carry forward a mental representation in which current topics are marked as likely subjects for anaphoric reference. • One account represents items in the current mental representation as activated to various degrees, thus enabling an anaphoric link to be made to the most salient.

Psycholinguistics • Those who include definite nouns within the class of anaphors point out that definiteness entails two different retrieval processes. • With some noun phrases, the antecedent will be in explicit focus (see c. below), while with others it will not (see d.). • c. Erica unlocked the door with difficulty. The door tended to stick. • d. Erica unlocked the door with difficulty. The key tended to stick.

Psycholinguistics