Psycholinguistics

by abdo Wed Apr 06, 2011 2:22 pm

Psycholinguistics

Psycholinguistics or psychology
of language is the study of the [You must be registered and logged in to see this link.]
and [You must be registered and logged in to see this link.]
factors that enable [You must be registered and logged in to see this link.]
to acquire, use, comprehend and produce [You must be registered and logged in to see this link.]. Initial forays into
psycholinguistics were largely philosophical ventures, due mainly to a lack of
cohesive data on how the human brain functioned. Modern research makes use of [You must be registered and logged in to see this link.], [You must be registered and logged in to see this link.], [You must be registered and logged in to see this link.], [You must be registered and logged in to see this link.], and [You must be registered and logged in to see this link.]
to study how the brain processes language. There are a number of subdisciplines
with non-invasive techniques for studying the neurological workings of the
brain; for example, [You must be registered and logged in to see this link.]
has become a field in its own right.

Psycholinguistics covers the
cognitive processes that make it possible to generate a grammatical and
meaningful [You must be registered and logged in to see this link.] out of [You must be registered and logged in to see this link.] and grammatical
structures, as well as the processes that make it possible to understand
utterances, words, [You must be registered and logged in to see this link.], etc. Developmental psycholinguistics studies children's
ability to learn language.

Areas of study

Psycholinguistics is
interdisciplinary and is studied by people in a variety of fields, such as [You must be registered and logged in to see this link.], [You must be registered and logged in to see this link.],
and [You must be registered and logged in to see this link.]. There
are several subdivisions within psycholinguistics that are based on the
components that make up human [You must be registered and logged in to see this link.].

Linguistic-related areas:

[You must be registered and logged in to see this link.] and [You must be registered and logged in to see this link.] are concerned
with the study of speech sounds. Within psycholinguistics, research
focuses on how the brain processes and understands these sounds.
[You must be registered and logged in to see this link.] is the study of word
structures, especially the relationships between related words (such as dog
and dogs) and the formation of words based on rules (such as plural
formation).
[You must be registered and logged in to see this link.] is the study of the
patterns which dictate how words are combined together to form sentences.
[You must be registered and logged in to see this link.] deals with the
[You must be registered and logged in to see this link.] of words and sentences. Where
syntax is concerned with the formal structure of sentences, semantics
deals with the actual meaning of sentences.
[You must be registered and logged in to see this link.] is concerned
with the role of [You must be registered and logged in to see this link.] in the interpretation of
meaning.

Psychology-related areas:

The
study of [You must be registered and logged in to see this link.] recognition
and [You must be registered and logged in to see this link.] examines the processes involved in
the extraction of [You must be registered and logged in to see this link.], [You must be registered and logged in to see this link.], [You must be registered and logged in to see this link.],
and [You must be registered and logged in to see this link.]
information from patterns in printed text.
Developmental
psycholinguistics studies infants' and children's ability to learn and
process language, usually with experimental or at least quantitative
methods (as opposed to naturalistic observations such as those made by [You must be registered and logged in to see this link.] in his
research on the development of children).

Theories

Theories about how language
works in the human mind attempt to account for, among other things, how we
associate meaning with the sounds (or signs) of language and how we use [You must be registered and logged in to see this link.]—that is, how we manage to
put words in the proper order to produce and understand the strings of words we
call "sentences". The first of these items—associating sound with
meaning—is the least controversial and is generally held to be an area in which
animal and human communication have at least some things in common (See [You must be registered and logged in to see this link.]).
Syntax, on the other hand, is controversial, and is the focus of the discussion
that follows.

There are essentially two
schools of thought as to how we manage to create syntactic sentences: (1)
syntax is an evolutionary product of increased human intelligence over time and
social factors that encouraged the development of spoken language; (2) language
exists because humans possess an innate ability, an access to what has been
called a "universal grammar". This view holds that the human ability
for syntax is "hard-wired" in the brain. This view claims, for
example, that complex syntactic features such as recursion are beyond even the
potential abilities of the most intelligent and social non-humans. (Recursion
includes the use of relative pronouns to refer back to earlier parts of a
sentence ("The girl whose car is blocking my view of the tree that I
planted last year is my friend.")) The innate view claims that the ability
to use syntax like that would not exist without an innate concept that contains
the underpinnings for the grammatical rules that produce recursion. Children acquiring
a language, thus, have a vast search space to explore among possible human
grammars, settling, logically, on the language(s) spoken or signed in their own
community of speakers. Such syntax is, according to the second point of view,
what defines human language and makes it different from even the most
sophisticated forms of animal communication.

The first view was prevalent
until about 1960 and is well represented by the mentalistic theories of [You must be registered and logged in to see this link.] and the
empiricist [You must be registered and logged in to see this link.].
As well, the school of psychology known as [You must be registered and logged in to see this link.] (see [You must be registered and logged in to see this link.] (1957)
by B.F.
Skinner) puts forth the point of view that language is behavior shaped by
conditioned response. The second point of view (the "innate" one) can
fairly be said to have begun with [You must be registered and logged in to see this link.]'s highly
critical review of Skinner's book in 1959 in the pages of the journal Language.^{[You must be registered and logged in to see this link.]}
That review started what has been termed "the [You must be registered and logged in to see this link.]"
in psychology.

The field of
psycholinguistics since then has been defined by reactions to Chomsky, pro and
con. The pro view still holds that the human ability to use syntax is
qualitatively different from any sort of animal communication. This ability may
have resulted from a favorable mutation or from an adaptation of skills evolved
for other purposes. In support of the latter view is the theory that language
serves group needs; better linguistic expression may have produced more
cohesion, cooperation, and potential for survival. The con view still holds
that language—including syntax—is an outgrowth of hundreds of thousands of
years of increasing intelligence and tens of thousands of years of human
interaction. From that view, syntax in language gradually increased group
cohesion and potential for survival. Language—syntax and all—is a cultural
artifact. This view challenges the "innate" view as scientifically
unfalsifiable; that is to say, it can't be tested; the fact that a particular,
conceivable syntactic structure does not exist in any of the world's finite
repertoire of languages is an interesting observation, but it is not proof of a
genetic constraint on possible forms, nor does it prove that such forms
couldn't exist or couldn't be learned.

Methodologies

Behavioral

Much methodology in
psycholinguistics takes the form of behavioral experiments incorporating a [You must be registered and logged in to see this link.].
In these types of studies, subjects are presented with some form of linguistic
input and asked to perform a task (e.g. make a judgment, reproduce the
stimulus, read a visually presented word aloud). Reaction times (usually on the
order of milliseconds) and proportion of correct responses are the most often
employed measures of performance. Such experiments often take advantage of [You must be registered and logged in to see this link.], whereby a "priming"
word or phrase appearing in the experiment can speed up the lexical decision
for a related "target" word later.^{[You must be registered and logged in to see this link.]}

Such tasks might include, for
example, asking the subject to convert nouns into verbs; e.g., "book"
suggests "to write," "water" suggests "to drink,"
and so on. Another experiment might present an active sentence such as
"Bob threw the ball to Bill" and a passive equivalent, "The ball
was thrown to Bill by Bob" and then ask the question, "Who threw the
ball?" We might then conclude (as is the case) that active sentences are
processed more easily (faster) than passive sentences. More interestingly, we
might also find out (as is the case) that some people are unable to understand
passive sentences; we might then make some tentative steps towards
understanding certain types of language deficits (generally grouped under the
broad term, [You must be registered and logged in to see this link.]).^{[You must be registered and logged in to see this link.]}

More recently, [You must be registered and logged in to see this link.] has been used
to study online language processing. Beginning with Rayner (1978)^{[You must be registered and logged in to see this link.]}
the importance and informativity of eye-movements during reading was
established. Tanenhaus et al.,^{[You must be registered and logged in to see this link.]}
have performed a number of visual-world eye-tracking studies to study the
cognitive processes related to spoken language. Since eye movements are closely
linked to the current focus of attention, language processing can be studied by
monitoring eye movements while a subject is presented with linguistic input.

Neuroimaging

Until the recent advent of [You must be registered and logged in to see this link.]
medical techniques, brain surgery was the preferred way for language
researchers to discover how language works in the brain. For example, severing
the [You must be registered and logged in to see this link.]
(the bundle of nerves that connects the two hemispheres of the brain) was at
one time a treatment for some forms of [You must be registered and logged in to see this link.]. Researchers could
then study the ways in which the comprehension and production of language were
affected by such drastic surgery. Where an illness made brain surgery
necessary, language researchers had an opportunity to pursue their research.

Newer, non-invasive
techniques now include brain imaging by positron
emission tomography (PET); functional
magnetic resonance imaging (fMRI); [You must be registered and logged in to see this link.] (ERPs) in [You must be registered and logged in to see this link.]
(EEG) and [You must be registered and logged in to see this link.]
(MEG); and transcranial
magnetic stimulation (TMS). Brain imaging techniques vary in their spatial
and temporal resolutions (fMRI has a resolution of a few thousand neurons per
pixel, and ERP has millisecond accuracy). Each type of methodology presents a
set of advantages and disadvantages for studying a particular problem in
psycholinguistics.

Computational

Computational modeling—e.g.
the DRC model of reading and word recognition proposed by Coltheart and
colleagues^{[You must be registered and logged in to see this link.]}—is
another methodology. It refers to the practice of setting up cognitive models
in the form of executable computer programs. Such programs are useful because
they require theorists to be explicit in their hypotheses and because they can
be used to generate accurate predictions for theoretical models that are so
complex that they render [You must be registered and logged in to see this link.] unreliable. Another
example of computational modeling is [You must be registered and logged in to see this link.] and [You must be registered and logged in to see this link.] model of speech perception.^{[You must be registered and logged in to see this link.]}

Issues and areas of research

Psycholinguistics is
concerned with the nature of the computations and processes that the brain
undergoes to comprehend and produce language. For example, the [You must be registered and logged in to see this link.] seeks to
describe how words are retrieved from the [You must be registered and logged in to see this link.]
when an individual hears or sees linguistic input.^{[You must be registered and logged in to see this link.]}

Recent research using new [You must be registered and logged in to see this link.]
imaging techniques seeks to shed light on just where certain language processes
occur in the brain.

There are a number of
unanswered questions in psycholinguistics, such as whether the human ability to
use syntax is based on innate mental structures or emerges from interaction
with other humans, and whether some animals can be taught the syntax of human
language.

Two other major subfields of
psycholinguistics investigate [You must be registered and logged in to see this link.], the process
by which infants acquire language, and second language
acquisition. In addition, it is much more difficult for adults to acquire second
languages than it is for infants to learn their first language (bilingual
infants are able to learn both of their native languages easily). Thus, sensitive
periods may exist during which language can be learned readily.^{[You must be registered and logged in to see this link.]}
A great deal of research in psycholinguistics focuses on how this ability
develops and diminishes over time. It also seems to be the case that the more
languages one knows, the easier it is to learn more.^{[You must be registered and logged in to see this link.]}

The field of [You must be registered and logged in to see this link.] deals with
language deficits that arise because of brain damage. Studies in aphasiology
can both offer advances in therapy for individuals suffering from aphasia, and
further insight into how the brain processes language.