Chapter 6 Language Processing in Mind

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Oct 25, 2013 (4 years and 2 months ago)

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Chapter 6 Language Processing in Mind

6.1 introduction


Why study language? ...
LANGUAGE

is a mirror of the mind in a deep
and significant sense. It is a product of human intelligence, created anew in
each individual by operations that lie far beyond the
reach of will or
consciousness. (Chomsky,

Reflections
on Language
, 1975) The study of
"language and mind" aims to model the workings of the mind in relation to
language. Since structures and connections in the mind are inevitably
unobservable, researchers
put forward hypotheses based on fragmentary
clues. This accounts for the high degree of controversy which surrounds
almost all areas of the subject. The label most usually given to the study of
"language and mind" is psycholinguistics, a term which is ofte
n perceived as
being trendy. It has therefore been somewhat overused in recent years, and
can be found applied to just about any linguistic topic.
PSYCHOLINGUISTICS
"proper" can perhaps be glossed as the storage, comprehension, production
and acquisition o
f language in any medium (Spoken or written).

Why study psycholinguistics?

PSYCHOLINGUISTICS

is concerned
primarily with investigating the psychological reality of linguistic structures.
Less modestly, it sometimes also produces findings whi
ch make their

own
mark on linguistic research, leading to the modification of theoretical ideas.


If we view the task of psycholinguistics in the light of the general
paradigm of cognitive psychology, it becomes identified with the search for
behavioral manifestations

of linguistic constructs. As psychology, in its modern
guise, uses an experimental methodology, it also follows that such behavioral
manifestations will be studied under experimental conditions, and it is
reasonable to see the last thirty years or so of p
sycholinguistics in terms of the
construction of ingenious laboratory techniques for pursuing this goal.

It is perhaps useful to distinguish psycholinguistics from the
PSYCHOLOGY OF LANGUAGE
, which deals with more general topics such
as the extent to whic
h language shapes thought, and from the
PSYCHOLOGY
OF COMMUNICATION
, which includes non
-
verbal communication such as
gestures and facial expressions. A possible divide within psycholinguistics is of
those who style themselves
COGNITIVE PSYCHOLINGUISTS
as
opposed
to
EXPERIMENTAL PSYCHOLINGUISTS.

The form are concerned above all

with making inferences about the content of the human mind, Whereas the
latter are

somewhat more concerned with empirical matters, such as speed of
response to a particular word. In
practice the two schools often overlap, but
extreme supporters of each way of thinking

sometimes perceive the gap as being a large one.


6.1.1 Evidence

Psycholinguistics attracts adherents from both linguistics and psychology,
though these often have somew
hat different approaches, particularly with
regard to methodology. Linguists tend to favor descriptions of spontaneous
speech as their main source of evidence, whereas psychologists mostly prefer
experimental studies. This divide highlights the fact that i
nvestigators face an
unsolvable paradox: the more naturalistic a study, the greater the number of
uncontrolled variables; the more rigidly the situation is controlled, the greater
the likelihood that the responses obtained will be untypical of real speech
situations. Care must therefore be taken to approach topics from different
angles, in the hope that the results will coincide.

The subjects of psycholinguistic investigation are normal adults and

children on the one hand, and aphasics
--
people with spee
ch disorders
--
on the
other. The primary assumption with regard to aphasic

patient that a breakdown
in some part of language could lead to an understanding of which components
might be independent of others.

6.1.2 Current issues

In spite of the varied appro
aches found in modern psycholinguistics, a
number of general trends and crucial issues can be identified. A major point of
agreement among various researchers is that the human language system is
likely to be "modular", in the sense of being constituted ou
t of a number of
separate but interacting components. A considerable amount of recent work
has attempted to elucidate this possible insight, although the number and
nature of these modules is far

from clear.


The realization that language organization is
likely to be modular has,
however, led to a major controversy concerning the integration of the modules,
as to whether they remain separate with links between them, or lead to an
overall central organizer which contains more abstract representations. For
e
xample, it is clear that at some level written and spoken representations of
words must be kept separate. One can therefore argue for an approach which
contains two separate lexicons, one for written speech, the other for spoken,
with links between them. O
n the other hand, one could suggest that these
separate lexicons lead ultimately to an abstract "master
-
lexicon" in which
differences between the various outputs are conflated. The issue is still
undecided. More recently, the question of "encapsulation" ha
s become
dominant, the extent to which each module works automatically and
independently, with its content sealed off from that of other modules (Fodor
1983, 1985).

A further problem is the relationship between
STRUCTURE

and
PROCESS
. It is generally agreed

that the mind is likely to contain certain
linguistic structures which are utilized in the course of various "processes",
such as comprehending or producing speech. Some researchers have argued
that structures and processes are linked only indirectly, oth
ers that the
connection is a close one. This debate is often phrased in terms of the
relationship between a linguist's grammar and a human "grammar", and the
extent to which the former has

PSYCHOLOGICAL REALITY.

Those who
believe that the relationship betw
een structure and process is weak tend to
accept the idea that a linguist's grammar may have "psychological reality" even
though there is no way in which it seems to be directly used in the processing
of speech. Chomsky (1980) for example, has argued that
any model which
represents the "best guess" as to the linguistic structures in the mind must be
regarded as "psychologically real" until superseded by a better model, even
though it has no relevance for comprehension or production. Other
researchers, howev
er, have argued for a closer relationship between structure
and process, suggesting that linguists' grammars ought to have a clear
relationship to linguistic processing. This controversy is unlikely to be solved in
the near future.


The three major stran
ds of psycholinguistic research are the
COMPREHENSION, PRODUCTION,

and

ACQUISITION

language. That is,
(1) How do people use their knowledge of language, and how do they
understand what they hear or read? (2) How do they produce messages that
others can u
nderstand in turn? (3) How language is represented in the mind
and how language is acquired?


Owing to the space limitation, this chapter will mainly introduce the
processes of language comprehension and production.


6.2 Language Comprehension

Most of ps
ycholinguistic research and theories are concerned with the
comprehension of text, but the assumption is that they are also relevant to
SPEECH COMPREHENSION
. If we assume that the processes involved in
TEXT

COMPREHENSION

are by and large the same processes

as those
involved in speech comprehension, then it should follow that those who have
good reading skills should also tend to have good speech comprehension
skills, whereas those who are poor at reading should also tend to be poor at
understanding speech.
This does, in fact, seem to be the case.

Reading and speech comprehension both involve several processes. It is
important for the reader or listener to take account of the grammatical structure
and the meaning of what is being presented. Meaning is extract
ed from text or
speech by relating what is presented to information stored in long
-
term
memory. There have been several attempts to explain how our previous
knowledge is applied to text and speech, and some of these attempts will be
discussed shortly.

6.2.
1 Word recognition

An initial step in understanding any message is the
RECOGNITION OF
WORDS
. As we have seen, the meaning of a sentence is determined in part
from the meanings of the words in it. Additionally, the recognition of a word
provides informatio
n that determines the syntactic structure of the rest of the
sentence. For instance, identifying a word also identifies what category it is,
thus determining what range of phrase structures it can occur in. And when we
recognize a verb like put, as well as

accessing its meaning, we also expect
certain types of complements to follow it; that is, it subcategorizes for an object
noun phrase and a locative phrase. When we hear the word

arrive
, we know
that it does not take an object. This kind of information is

made available to
speakers by recognizing a word and accessing the information that they have
in their memory concerning it. Identifying words is such an effortless task under
most conditions that we don' t realize how difficult it really is; designing a
computer system to accomplish this task, for instance, has proven virtually
impossible. First recall the, sheer number of words that any given person
knows: the average six
-
year
-
old knows already about 14,000 words. A different
kind of difficulty is prese
nted by ambiguity, where two words with different
meanings sound the same. Despite these difficulties, the subjects are able to
identify what they hear quite quickly. One source of evidence that this is the
case comes from "shadowing experiments" in which

people repeat aloud what
they have just heard over a tape recorder. Ss can fluently and accurately
repeat what they have heard with a lag of considerably less than a second.
They cannot do this if what they hear is nonsense or a foreign language.

How do w
e go about recognizing words then? One common sense view
that receives a lot of support from experimental evidence is that as soon as
people hear speech, they start narrowing down the possible words that they
may be hearing. If the first sound that they he
ar is /s/, that eliminates all words
beginning with other sounds; if the next sound is/p/, many other possibilities
are eliminated. A word is identified as soon as there is only one possibility left.
This account is referred to as the
COHORT THEORY
and hyp
othesizes that
auditory word recognition begins with the formation of a group of words at the
perception of the initial sound and proceeds sound by sound with the cohort of
words decreasing as more sounds are perceived. This theory can be
expanded to deal
with written materials as welt. Several experiments have
supported this view of word recognition. One obvious prediction of this model
is that if the beginning sound or letter of a word is missing, recognition will be
much more difficult, perhaps even impo
ssible. As early as 1900, experiments
showed that word recognition is much more impaired by the mispronunciation
of the initial letter of a word than by the mispronunciation of the final letter. This
suggests that this model is correct; if the end of the w
ord is missing, it can be
predicted based on the initial portion, while it is much more difficult to use the
end to predict the early part of the word.

One of the most important factors that affects word recognition is how
frequently the word is used in a
given discourse or context. This
FREQUENCY
EFFECT
describes the additional ease with which a word is accessed due to
its more frequent usage in the language. For example, words like
better

or
TV
occur more often than
debtor

or
mortgage
. This effect is not
easy to explain
assuming the beginning
-
to
-
end word recognition approach sketched above.
One possible explanation of the frequency effect is that the lexicon is partially
organized by frequency rather than simply in terms of the sounds in
beginning
-
to
-
end o
rder.

People also recognize a word faster when they have just heard it or read
it than when they have not recently encountered it. Frequent words are likely to
have been encountered more recently than infrequent words, so it is possible
to explain the freq
uency effect as a recently effect and reduce the number of
separate effects that have to be explained.
RECENCY EFFECTS

describe
the additional ease with which a word is accessed due to its repeated
occurrence in the discourse or context. However, again, t
he recently effect
does not gibe with the simple beginning
-
to
-
end identification algorithm
sketched above.

Another factor that is involved in word recognition is
COTEXT.

People
recognize a word more readily when the preceding words provide an
appropriate c
ontext for it. For example, in the sentence

This is the aorta
,
people are not given any context that helps identify the word

aorta
. But in the
sentence
The heart surgeon carefully cut into the wall of the right aorta,

many
people would find that the cue of

the heart surgeon helps them to identify the
word more quickly. One mechanism that has been proposed to account for this
kind of context effect is a
SEMANTIC ASSOCIATION NETWORK
. This
network represents the relationships between various semantically relat
ed
words. Word recognition is thought to be faster when other members of the
association network are provided in the discourse. It is obvious that the
meaning of a word is tied to our understanding and general knowledge of the
concept to which it refers. T
hus, it is not unreason
-

able to suppose that hearing the words heart surgeon not only activates the
direct meaning of the words heart surgeon, but also makes a number of
associated con
cepts that are more available to the hearer, such as those
involved in the physiology of the heart, modern surgical procedures, and so on.
These concepts are in turn linked to the words that are used to refer to them.

6.2.2 Lexical ambiguity

Much research

has centered on how ambiguous words such as bug or
rose are understood. There are two main theories: (1) all the meanings
associated with the word are accessed, and (2) only one meaning is accessed
initially. Support for the first position comes from exp
eriments such as the
following. When people are asked to finish a sentence, they take longer when
the fragment to be finished contains an ambiguous word than when the
ambiguous word is replaced by an unambiguous term, as in the following
sentences:


ex
. 6
-
1

a.

After taking the right turn at the intersection…..

(
right

is ambiguous:
correct

vs.
rightward
)

b.

After taking the left turn at the intersection…

(left
is unambiguous)

What this delay suggests is that all meanings of ambiguous words are
accessed and th
at time has to be taken to decide among them.

However, other experiments suggest that under some circumstances,
only one meaning is initially accessed. Two of the effects mentioned above
have been shown to be important here: the frequency and context effe
cts. First,
if one of the meanings is much more frequent than the other, people tend to
assume that the word has the more frequent meaning. The word
chair
, for
example, has at least two meanings
--
an object to sit on and the head of a
department or committe
e
--
but the former occurs much more often in speech
than the latter, and people often appear to recognize only the more frequent
meaning soon after the word
chair

is presented to them. This seems to
suggest that only one meaning is initially considered, at
least for words whose
various meanings differ markedly in frequency of occurrence.

The semantic context effect also plays a significant part in which
meaning is the most appropriate. When a word like bug is seen in the context
of
spy
, it is reliably identi
fied as meaning "a listening device"; but in the context
of
spiders
and
roaches

it is identified as meaning "an insect".

6. 2.3 Syntactic processing

Once a word has been identified, it is used to construct a syntactic
structure. In some cases this is quit
e straightforward. Psycholinguists generally
assume that the syntactic structure is built as soon as possible rather than
waiting to see what the whole string of words is before deciding what structure
it has. The reason for this assumption is that people
normally already know
what the beginning of the sentence means before they hear the whole thing;
this must be the case given the common experience we all have of being able
to fill in a word that someone else we have been listening to is groping for. The
s
hadowing task mentioned earlier proves the same point. Sometimes when
people are shadowing, they mistake what they hear and say a word that is not
on the script that they are repeating aloud. This word is generally syntactically
and semantically reasonable

given the context. If all the words in a sentence
are unambiguous or have only one possible category and those categories fit
only one phrase structure, it is not hard to understand how people can build
the correct structure and interpret it so quickly.
For example, in

the jealous
woman went away
, the word
the

can only be a determiner,
woman

is a noun,
and the combination forms a noun phrase or nominal word group;
went

is a
past tense verb,
away
is a particle, and the combination of the two makes a
verb p
hrase; finally, the combination of a noun phrase and a verb phrase
makes a sentence. From this example there is no reason to think that the
process of determining the structure of a sentence is difficult.

However, as always, there are complications due to
the ambiguity of
individual words and to the different possible ways that words can be fit into
phrases. Sometimes there is no way to determine which structure and
meaning a sentence has. For example, there are two possible structures
associated with the s
entence
The cop saw

the spy with the binoculars
. The
ambiguity lies in how the prepositional phrase

with the binoculars

fits into the
rest of the sentence; it can be a complement of the verb

see
, in which case it
means that the cop employed binoculars in o
rder to see the spy, or it can be
part of the noun phrase, in which case it specifies that the spy has binoculars.

Some ambiguities are due to the ambiguous category of some of the
words in the sentence. In the expression
the desert trains
, should
desert

b
e
taken as the subject of the verb

trains
, or is
desert

a modifier of the noun

trains

?
If the sentence continues
men to be hardy
, the first structure is correct, but if it
continues

seldom run on time
, the latter is appropriate.

One interesting phenomenon

concerning certain ambiguous sentences is
called the "garden path",
GARDEN PATH

sentences are sentences that are
initially interpreted with a different structure than they actually have. It typically
takes quite a long time to figure out what the other st
ructure is if the first choice
turns out to be incorrect. Sometimes people never figure it out. They have
been "led up the garden path," fooled into thinking the sentence has a different
structure than it has. Reduced relative clauses quite frequently caus
e this
feeling of having been garden
-
pathed. For example,
The horse raced past
the barn fell

means "the horse that was raced past the barn fell," but even
when this is explained, many people have trouble figuring out how it fits
together.

As with lexical
ambiguity, an important question in sentence processing is
how people decide which structure an ambiguous sentence has. The
alternatives are that people either consider all possibilities and decide which is
the best, or else they use some strategy to decid
e which structure to consider
first. If that structure does not work out, they may reconsider. This garden path
phenomenon suggests that for at least some ambiguities, people try one
analysis of an ambiguous sequence of words first, and only become aware o
f
the other possibility when the one tried first does not work out. In the example
above, people realize that there is something wrong with their initial analysis of
the sentence because

fell
cannot be fit into the structure that they have settled
on initi
ally.


Several suggestions have been made about how people decide which
analysis to try first. One guess is that there is a strong tendency to build as little
structure as possible. For example, if the first word in sentence is
the
, an
infinite number of s
tructures could potentially follow;
the

is a determiner and
unambiguously initiates a noun phrase, but that noun phrase can serve as a
subject of a sentence, as a possessive phrase modifying the subject noun, as
a possessive phrase modifying a possessive n
oun, etc. Because of recursion,
there are an infinite number of possibilities.

It would be inefficient for people to assume all these infinite structures
until they get some positive evidence for one of them. And if they arbitrarily
choose one of the possi
bilities, they are most likely to choose the simplest. The
idea is that people initially construct the simplest (or least complex) syntactic
structure when interpreting the structure of sentences. This is called the
MINIMAL ATTACHMENT THEORY
.

There are oth
er types of information that people can use to choose the
appropriate analysis for an ambiguous sentence as well. As with words, the
semantic interpretation sometimes determines which is the most likely
interpretation. Returning to the ambiguity above, it
is equally likely that
someone can employ binoculars to see a spy or that a spy should have
binoculars. But if the word
binoculars

is replaced with him by Galileo, the great
Italian the word
revolver,

the situation changes. A spy with a revolver is likely
enough to be seen, but it isn't possible to see using a revolver. Therefore, the
choice between the possibilities can be made based on the pragmatic
plausibility of the two interpretations.

6.2.4 Semantics and sentence memory

One of the dearest demonstrat
ions that memory representations are not
syntactic under certain conditions arises when we present subjects with short
stories, each of which contains a key sentence. At some point after the subject
hears this sentence. He is presented with a test sentence

and has to decide
whether it is identical in all respects with any sentence he has heard in the
story. The test sentence is con
-

strutted in such a way as to bear one of a
number of relationships to the key sentence and, of course, on any trial subject
do
es not know which sentence in the story is the key sentence. To illustrate,
one story which has been used in this sort of study described the invention of
the telescope and included ex. 6
-
2a as its key sentence.

ex. 6
-
2a


Galileo, the great Italian scie
ntist, sent a letter about it to him.

The last sentence, which could immediately follow the key sentence or
follow it after an interval of 60 or 120 syllables, could either be identical with (a),
related to (a) via
PASSIVE
, related to (a) via another synta
ctic rule not
involving any change in meaning, or related to (a) via switching the subject and
indirect object NPs
--
a switch which involves a marked change in meaning.
These last three possibilities are illustrated in (b)
---
(d).


b. A letter about it w
as sent to him by Galileo, the great Italian
scientist.


c. Galileo, the great Italian scientist, sent him a letter about it.

d .He sent a letter about it to Galileo, the great Italian scientist.


The results of the study were that if the test sentence

was presented
immediately after the key sentence, the subjects would recognize any change,
syntactic or semantic. After as little as 60 syllables, however, Ss were almost
as likely to respond that they had heard (b) or (c) in the story as they were to
res
pond positively to (a) itself, i.e. after this short period they were not capable
of recognizing syntactic changes which did not also involve a change of
meaning. For (d) subjects' performance was much more accurate and, even
after 120 syllables, they were

detecting semantic changes with almost 100
percent accuracy. This seems to indicate that the syntactic details of linguistic
material are not usually stored for very long and that it is a representation of a
sentence's meaning which a subject has availabl
e in his memory under normal
circumstances. Note that this does not demand that syntactic details have no
role in memory. In fact, the results of this study are consistent with such details
being available to memory for a short time and it may be that unde
r certain
conditions the experimentalist can gain access to this level of representation. It
is, perhaps, not insignificant that the present 'study uses materials in
structured story form, whereas most of the earlier memory studies we have
mentioned use se
ntences in isolation as stimuli.

Rather more interesting work than the above has taken place within the
framework of
ASSIMILATION THEORY
. This is a rather difficult position to
define but it differs from approaches using semantic features in its emphasis
o
n the importance of background knowledge in "normal" situations where we
might memorize linguistic material. There is evidence to indicate that, for some
levels of memory representation, this background knowledge constitutes a
necessary condition, i.e. wit
hout the knowledge the appropriate representation
cannot be set up. This evidence arises when subjects are presented with
structured texts and are instructed to comprehend them and remember as
much of their content as possible. The texts are chosen to desc
ribe unlikely
states of affairs but the lexical items and syntactic structures they use are
familiar enough. One group of subjects simply hear the text, a second hear the
text and are then shown a picture providing an appropriate context for the text
and a

third group are shown the picture before they hear the text. The results
are quite spectacular, with the third group remembering the content of the text
much more fully than either of the other two, and this would seem to require
that subjects in this gro
up managed to build up a level of representation which
they could use in this task. This level of representation was denied by the first
two groups, despite the familiarity with the lexical items and syntax of the text.

Assimilation Theory has opened up ne
w areas of memory research over
the last few years and it seems likely that it will direct investigation for some
time in the future. Its major weakness is that it has said little about the details of
semantic representations for sentences beyond the fact
that such
representations must allow the processes briefly described here to take place.
In particular, it says nothing about the semantic representation of words and it
is self
-
evident that the understanding process involves "looking up" the
meanings of p
articular words in some sort of psychological dictionary or
lexicon.

6.2.5 Basic processes in reading

Eye movement
. A useful way of investigating some of the processes
involved in reading is to study the
EYE MOVEMENTS

of people reading. While
we feel that

our eyes move smoothly across a page of text, the reality is quite
different. Our eyes actually make a series of rapid movements known as
"saccades", and between saccades there are fixation periods lasting for
approximately 250 milliseconds. A point towar
ds the beginning of a word is
usually fixated, and there is a distance of approximately eight letters or spaces
between successive fixations. While most fixations typically move forwards in
the text, around 10 or 15 % of them involve the eyes fixating an
earlier part of
the text than the previous fixation. Of particular importance, information is
obtained from the text only during fixations and not at all during saccades.

The perceptual span
. How much information is extracted from a single
fixation? Variou
s methods have been used to measure what is known as the
PERCEPTUAL SPAN
, which is the range of letters from which useful
information is extracted. Not surprisingly, the perceptual span varies
depending on factors such as the size of the print, the complex
ity of the text,
and so on. It is typically the case, however, that the perceptual span
encompasses about three or four letters to the left of fixation and some fifteen
letters to the right of fixation. The opposite pattern is found in readers of
Hebrew, w
ho read from right to left. What appears to be happening is that it is
more valuable to look ahead in the text rather than to look backwards to words
which have already been processed.

The fact that the perceptual span covers almost 20 letters means that
s
ome of the letters included in it do not fall within the focal region of the eye,
which is the area of high acuity. What information is extracted from the area
lying outside the fovea? Fairly complex studies have revealed that meaning is
not extracted, bu
t that information about the identity of the letters is obtained.


The immediacy assumption
. At what point is meaning extracted from
the words in a text? The reader is supposed to carry out the processes
required to understand each word and its relations
hip to previous words in the
sentence as soon as that word is encountered; this is known as the
IMMEDIACY ASSUMPTION.


Carpenter and Daneman (1981) obtained some evidence consistent
with the immediacy assumption. They included the following two sentences
in
an account of a fishing contest:


ex. 6
-
3


Tomorrow was the annual, one
-
day fishing contest and fishermen
would invade the place. Some of the best bass guitarists in the country would
come to this spot.

These sentences were written specifically t
o confuse the subjects. It is
natural to interpret
bass

as referring to a kind of fish, but the following word
guitarists makes it clear that the appropriate meaning of
bass

is its musical one.
Most readers fixated an unusually long time on the word
guitar
ists
, which
suggests that the ambiguity and its resolution were noticed almost
immediately.

There is other evidence which indicates that the immediacy assumption
is over
-
simplified. The fact that most readers sometimes move their eyes back
to earlier parts

of a text suggests that the meaning of text is not always
extracted immediately. In addition, readers sometimes fixate the same word
more than once, which is contrary to the spirit of the immediacy assumption.

6.3 Discourse/text interpretations

Discourse

serves as a context, affecting sentence and word
-
level
interpretation, tipping the interpretation of what would otherwise be ambiguous
words or phrases in a certain direction. For example, some sentences can be
interpreted literally (according to standard

usage of the words) or figuratively
(by deviating from what we understand to be the standard significance of the
words for some special meaning or effect). Context can prompt readers to
engage in one or the other.

When we are trying to understand a senten
ce, we often make use of
information that is not contained directly within the sentence itself. This is
known as contextual information, and we can distinguish between two kinds of
context: general and specific.

GENERAL CONTEXT EFFECTS

occur when
our gener
al knowledge about the world influences language comprehension.
SPECIFIC CONTEXT EFFECTS

involve information obtained from earlier
parts of a discourse.


General context effects occur all the time, because a crucial aspect of
language comprehension involv
es making use of any relevant general
knowledge that we possess. This can be demonstrated at an anecdotal level.
When the author first visited the United States, he was baffled by the
commentaries on baseball games. He could understand each word and
senten
ce at some level, but Full comprehension was impossible because of
his imperfect knowledge of the rules of baseball.


Specific context effects can operate in a similar fashion, as was shown
by John Bransford and Marcia Johnson (1972). They gave their subj
ects the
passage in the panel below:

The procedure is actually quite simple. First you arrange items into
different groups. Of course one pile may be sufficient depending on how much
there is to do. If you have to go somewhere else due to lack of facilitie
s, that is
the next step; otherwise, you are pretty well set. It is important not to overdo
things. That is, it is better to do too few things at once rather than too many. In
the short run this may not seem important but complications can easily arise. A
mistake can be expensive as well. At first, the whole procedure will seem
complicated. Soon, however, it will become just another facet of life. It is
difficult to foresee any end to the necessity for this task in the immediate future,
but then, one never
can tell. After the procedure is completed one arranges the
materials into their appropriate places. Eventually, they will be used once more
and the whole cycle will then have to be
repeated. However, that is part of life.

Subjects who were given this pass
age on its own found it (as you
probably did) difficult to comprehend. Those who were provided with an
appropriate context in the form of the title, "Washing clothes", on the other
hand, found the same passage reasonably easy to understand.

6.3.1 Schemata

and inference drawing

It is believed that

SCHEMATA,

meaning packets of stored knowledge,
play an important rote in language processing. The futures of schemata are as
follows:


(
1) Schemata can vary considerably in the information they contain,
from


the very simple to the very complex.


(2) Schemata are frequently organized hierarchically; for example,
in


addition to a rather general restaurant schema or script, we probably also

have more specific restaurant schemata for different kinds
of restaurant
( e. g.

fast
-
food places, up
-
market French restaurants, and so on ).


(3) Schemata operate in a top
-
down or conceptually driven way to

facilitate interpretation of environmental stimuli.

There are various characteristics of language pro
cessing which
indicate the key role played by schematic and other stored knowledge. For
example, language comprehension frequently requires us to go far beyond the
literal meanings of the sentences we read or hear. Essential information is
often only impli
ed, so that it is necessary to draw inferences in order to
understand fully what is intended. You might think that only rarely do
inferences need to be drawn to fill in the gaps in discourse. Consider the
following sentence:
Three turtles rested on a floa
ting log, and a fish swam
beneath them.

Most of us would use our stored knowledge of spatial
relationships to draw the inference that the fish swam beneath the log as well
as beneath the three turtles. This sort of inference is drawn so effortlessly that
w
e are generally unaware that we have drawn an inference at all.

How do we know that someone has drawn a particular inference?
According to Bransford, Barclay, and Franks (1972), the inferences which
people draw are stored in long
-
term memory along with inf
ormation about the
sentences actually presented. As a result, they will sometimes mistakenly
believe on a subsequent memory test that they previously heard or saw an
inference. Bransford et al. (1972) presented their subjects with sentences such
as the one

above about the fish and the turtles. Later on, they were given a
test of recognition memory. Subjects were confident that they had previously
been presented with sentences which they had actually heard before (i. e.
Three turtles rested on a floating log
, and a fish swam beneath them

). They
were equally confident, however, that they had heard sentences which
involved an inference from what they had heard (e. g.
Three turtles rested on a
floating log, and a fish swam beneath it,

although in the actual se
ntence, the
fish swam beneath
them

). This indicates that spontaneous spatial inferences
are made.

No complete theory of what is involved in inference drawing is available.
However, schemata or scripts presumably play a part. In discussion of
schemata, we
believe that some of the errors observed in memory seem to
reflect the use of schemata. For example, people made use of a restaurant
schema or script to understand a story about Jack eating out at a restaurant.
Subsequently, they falsely recognized sentenc
es fitting into the schema but
not actually included in the story (e. g.
Jack sat down at the table
. ). Schemata
thus lead people to draw schema
-
relevant inferences which facilitate
comprehension but which may impair memory.

An important theoretical issue
is whether schematic knowledge is always
used at the time of comprehension and storage or whether it is sometimes
used at the time of retrieval. So far as inferences are concerned, there is
reasonably strong evidence that many of them are drawn during the
comprehension process. For example, in a study the length of time that the
eyes fixated on the various words in a text was measured. The fixation time on
a word (e. g.
knife

) was less if the same word had been presented before than
if a general word had b
een used earlier in the text (e. g.
knife

rather than
weapon

). Presumably this happened because it took the subjects some time
to work out that a knife was the weapon referred to previously. This long
fixation of
knife

following
weapon

did not occur, howe
ver, if the reference to
weapon had included sufficient information for the reader to make the
inference that the
weapon

was indeed a
knife
. The implication is that the
inference was drawn during comprehension of the word
weapon
.

There is also evidence tha
t retrieval processes can be systematically
affected by prior knowledge in the form of schemata. Anderson and Pichert
(1978) asked subjects to read a story about a house from the perspective of a
prospective buyer or of a prospective burglar. After the sub
jects had recalled
the story, they were then asked to recall the story again on the basis of the
alternative perspective. The key finding was that subjects recalled more
information relevant to the alternative perspective on the second recall than on
the f
irst, presumably because the relevant schemata guided the recall process.
As one of the subjects reported: "When he gave me the homebuyer
perspective, I remembered the end of the story, you know, about the leak in the
roof. The first lime through I knew th
ere was an ending, but I couldn't
remember what it was. But it just popped into my mind when I thought about
the story from the homebuyer perspective" (Anderson and Pichert, 1978:10).

6.3.2 Story structure

Our comprehension of and memory for stories are h
ighly "selective'', in
the sense that we focus on the central theme of the story rather than on the
relatively unimportant details. This was. demonstrated convincingly by
Gomulicki (1956). He asked one group of subjects to write a summary of a
story that w
as visible in front of them. He asked a second group to read the
story and then to recall it from memory. The third group of subjects were shown
the summaries and the recalls, and were generally unable to tell which were
which. These findings indicate that

what is extracted from a story and then
remembered closely resembles a summary in its emphasis on the main theme
of that story.

Van Dijk and Kintsch (1983) have proposed a theory of story processing.
They argued that a story is first of all processed so t
hat the individual
propositions (i. e. assertions that may be true or false) are extracted.

Evidence that propositions play a major role in sentence comprehension
was obtained by Kintsch (1973). They presented sentences which contained
approximately the sa
me number of words, but which varied in terms of the
number of propositions. For example, the sentence,

Cleopatra' s downfall lay
in her foolish trust of the fickle political figures of the Roman world
, contains
twice as many propositions as the sentence,

Romulus, the legendary
founder of Rome, took the women of the Sabine by force
. Kintsch (1973)
discovered that reading time for such sentences increased by approximately
one second for each additional proposition.

According to van Dijk and Kintsch (1983),

the propositions of a story
enter into a short
-
term working buffer of limited capacity, which is similar to the
working memory system. The working memory is termed as a combined
temporary memory and mental work space in which recent stimuli are briefly
he
ld, either for rehearsal and recall or for meaningful integration with other
knowledge. When the buffer contains a number of propositions, the reader or
listener tries to relate them to each other in a coherent fashion. In general
terms, subsequent ability

to remember the propositions depends on the length
of time they spend in the working buffer. Those propositions which are highly
relevant to the main theme of a story tend to be stored for a relatively long time
in the working buffer. The reason is that s
uch propositions are generally well
connected to other propositions in the buffer,
-
and so retaining them in the
buffer facilitates the task of making coherent sense of the story. It follows from
these theoretical assumptions that thematic information shou
ld be better
remembered than non
-
thematic information.

Van Dijk and Kintsch (1983) argued that there were additional processes
involved in the task of understanding the gist or
MACROSTRUCTURE
of a
story. More specifically, they claimed that readers or lis
teners make extensive
use of their general knowledge to work out the major theme of a story. This
leads to the production of

MACROPROPOSITIONS,

which are general
propositions used to form an overall macrostructure of the story. There are
substantial diffe
rences in the kinds of knowledge that individual people can
bring to bear on story understanding. As a result, the way in which the working
buffer is used and the story macrostructure which is formed will also differ from
one person to the next. The theory

proposed by van Dijk and Kintsch (1983),
even though it has enhanced our understanding of story processing, suffers
from the limitation that it is not precisely enough formulated to account in detail
for such individual differences.


6.4 Language product
ion

More is known about language comprehension than about language
production. This is perhaps because it is generally easier for an experimenter
to exercise control over the comprehension material than to constrain a
subject's language production. Further
more, language production cannot be
considered purely from the perspective of a theory of language.
LANGUAGE
PRODUCTION

is very definitely a goal
-
directed activity, in the sense that
people speak and write in order to make friends, influence people, convey

information, and so on.

The two forms of language production considered in this section are
speech production and writing. Speech production has been investigated more
thoroughly than writing, but the reasons for this are not clear.

6.4.1 Speech product
ion

The usual approach in cognitive psychology is to set the subject a task,
and then to assess how accurately or efficiently that task has been performed.
This approach doesn't work, however, when we are investigating speech
production. If we tell our sub
jects what we want them to say, then the
spontaneity of normal speech is completely lost. If, on the other hand, we leave
our subjects free to say whatever they like on a given topic, then we have very
little experimental control over what is said. One app
roach is to ask people to
speak on a particular topic, and to make a tape recording of what they say.
Another, more useful approach is to ask people to make a collection of the
speech errors which they make in everyday speech.

At a theoretical level, a pro
mising start has been made by Garrett(1976;
1984). He argued that producing speech is a much more complex matter than
it might appear to be from our everyday experience. According to his model,
there are altogether five different levels of representation i
nvolved in speaking
a sentence, and they occur in the following sequence:

(1) The
message
-
level representation:

this is an abstract,
pre
-
linguistic representation of the idea or ideas that the speaker wants
to communicate.

(2) The
functional
-
level represen
tation:

this is an outline of the
proposed utterance having grammatical structure; in other words, the
slots for nouns, adjectives, and so on are allocated, but there are no
actual words to fill the slots.


(3) The
positional
-
level representation:

thi
s differs from the
functional level representation in that it incorporates the words of the
sentence that is to be produced.


(4) The

phonetic
-
level representation:

of the necessary
information about the ways the intended sentence are pronounced.



(5) The

articulatory
-
level representation:
this is the final
representation, and contains a set of instructions for articulating the
words in the sentence in the correct order.


This complex theory of speech production has not as yet been tested

thoroughly. However, there is support for some of its major assumptions. In
essence, Garret (
1984
) claimed that the speaker engages in reasonably
elaborate pl
anning before beginning to speak. One way of testing this notion is
to consider the sorts of error that people make while talking. If, for example,
sounds or words from the end of a sentence intrude into the early part of a
sentence, then this provides evi
dence for the notion of forward planning. The
classic error of this type is the
SPOONERISM

(
or

SLIP OF THE TONGUE
),
where the initial letter or letters of two words are transposed.

Other errors also demonstrate the existence of forward planning. An
ANTICIP
ATION ERROR

occurs when a word is spoken earlier in the sentence
than it should be (e. g.
The school is at school
. ) A similar type of error is the

EXCHANGE ERROR
, in which two items within a sentence are swapped (e. g.

This is the happiest life of my day.

)

In general terms, the demands of speech production are so great that
production of speech and planning for the next utterance are difficult to
combine satisfactorily. Pauses are used in an attempt to ease these
processing demands, but even with pauses,
spontaneous speech is usually
characterized by a variety of errors. The position is rather different when
people have prepared the content (but not the wording) of what they intend to
say (e.g. before a public lecture). Such prepared speech exhibits many f
ewer
grammatical and stylistic errors than does spontaneous speech.

According to Garrett (1976; 1984 ), speakers decide on the grammatical
structure of a proposed utterance in the functional
-
level representation, and
then select the appropriate words to fi
t into that structure in the subsequent
position
-
level representation. Given this sequence, it would be possible for the
grammatical structure of a spoken sentence to be correct even though some of
the words were incorrectly positioned. Precisely this is f
ound with
MORPHEME
-
EXCHANGE ERRORS, in which the roots or basic forms of two
words are switched leaving the grammatical structure unchanged (e. g.
He has
already trunked two packs
. )

Why is human speech production so prone to error? According to Dell
(1986
), it is the price we pay for having such a flexible speech
-

production
system. Its flexibility has the great advantage of allowing us to produce novel
sentences. Indeed, most speech errors involve novelty, but simply novelty of
an unwanted kind. If we had

a very rigid speech
-
production system, it might
prevent errors from occurring, but we would suffer the disadvantage of very
stereotyped utterances.

6.4.2 Written language

Written language differs from spoken language in a number of ways. The
hesitations,

grammatical errors, and interchanges of words characteristic of
spoken language are largely, or entirely, absent from written language. It
should therefore come as no surprise to discover that theories of the
processes involved in writing differ significa
ntly from those put forward to
explain speech production.

One of the most detailed theories of the writing process was proposed by
Hayes and Flower ( 1986 ). According to them, writing essentially consists of
three inter
-
related processes:


( 1 ) The

planning process
, which involves producing ideas and
arranging them into a writing plan appropriate to the writer ' s goals.


( 2 ) The
sentence generation process
, which translates writing
plan into actual sentences that can be written down.


(
3 ) The
revision process
, which involves an evaluation what has
been written so far; this evaluation can encompass individual words at
one extreme or the overall structure of the writing at the other extreme.

In general, the processes operate in the order:

planning, sentence
generation, and revision; however it is quite common for the writer to return to
the planning process after several sentences have been generated and
revised, especially with longer pieces of writing.

Writing plans are obviously much i
nfluenced by the relevant knowledge
that the writer possesses about the topic to be written about. Another less
obvious factor determining the quality of the writing plan is

STRATEGIC
KNOWLEDGE
, which is knowledge of the methods used in constructing a
writ
ing plan in order to make it coherent and well
-
organized. Children often
lack such strategic knowledge
--
they tend to make use of a
KNOWLEDGE
-
TELLING STRATEGY
, where they simply write down
everything they can think of that is relevant to a topic without org
anizing the
information in any way (Scardamalia and Bereiter, 1987). Skilled writers, in
contrast, possess strategic knowledge, which enables them to make use of a
K
NOWLEDGE
-
TRANSFORMING STRATEGY.

This involves focusing on
potential problems within the pla
nning process (e. g. "Are the main points
arranged in the most logical order?").

The writing plan constructed during the planning process is generally
much shorter and sketchier than the written story or essay itself. Kaufer, Hayes,
and Flower (1986) asked

writers to write down an outline of their essays
corresponding to the writing plan. They discovered that the subsequent essay
was always at least eight times longer than the outline.

Kaufer et al. (1986) discovered that expert writers produced larger
sen
tence fragments than less skilled writers: 11.2 words versus 7.3 words on
average. However, the similarities outweighed the differences. Both groups of
writers wrote down approximately 75 % of the sentence fragments they
produced in their verbal protocols.

They also found that when sentence parts
were altered, it was almost always the last part to be produced that was altered.
One of the interesting and perhaps surprising findings about the revision
process is that expert writers typically spend longer than

non
-
expert writers on
revision. There are two main reasons for this. First, expert writers are more
skilled at detecting errors that require revision. For example, in a study by
Hayes and others (1985), expert writers detected approximately 60% more
probl
ems in a writers. Second, expert writers tend to focus on the overall
coherence and structure of what has been written, whereas non
-
expert writers
concentrate more on individual words and phrases. It takes much more time to
change the structure of a piece
of writing than simply to alter some of the
words.

How adequate is the theoretical approach to writing advocated by Hayes
and Flower (1986)? On the positive side, they have been reasonably
successful in identifying some of the major differences between str
ategies
used by expert and non
-
expert writers. This is of value in terms of suggesting
ways in which poor writers could improve their writing skills.

Probably the major limitation of their approach is the emphasis they
place on verbal protocols


i.e. the
spoken thoughts of writers engaged in
writing. While there may be conscious awareness of many of the process
involved in sentence generation and revision, it seems probable that much of
the planning process occurs below the conscious level and thus cannot
be
verbalized.


Further Reading

Aitchison, J.1990. Language and Mind: Psycholinguistics, in N. E. Collinge
( ed. ) An
Encyclopaedia of Language
, Routledge, 333
-
370.

Aitchison, J.1998.
The Articulate Mammal: An Introduction to Psycholinguistics.

Routledge.

Carrol, D.V. 1994/1999.

Psychology of Language ( 2
nd

edition)
.Monterey, CA:
Brooks/Cole Publishing Co

Dijkstra, T & De Smelt, K. (Eds.)1996.
Computational Psycholinguistics
.
London: Taylor & Francis Ltd, 3
-
23

Eysenck, M. W. 1993.

Principles of Cognitive Ps
ychology
. LEA, Hillsdale,
102
-
130.

Foss, D., & Hakes, D. 1978.
Psycholinguistics

:
An Introduction to the
Psychology of Language.

Englewood Cliffs, NJ: Prentice
-
Hall, 61
-

229.

Garman, Mi. 1990. Psycholinguistics . Cambridge: Cambridge University
Press.

Gl
eason, J.B. 1998.
Psycholinguistics (second edition ).

Harcourt Brace
College Publishers, 1
-

150, 223
-

339 and 409
-

435.

Harley, T. 1995.
The Psychology of Language:

From Data to Theory.
East
Sussex: Erlbaup (UK) Taylor & Francis, 31
-

100, 139
-

174 and

207
-

277.

Kess, J. F. 1992.
Psycholinguistics: Psychology, Linguistics and the Study of
Natural Language.

Amsterdam: John Benjamins, 29
-

222.

Steinberg, D.D. 1993.
An Introduction to Psycholinguistics.

London: Longman,
5
-

132.

桂诗春,
2000
。《新编心理语言学》。上海外语教育
出版社。