ttention with referenceto at least one Alternative Model.
'Attention' - A state of specific alertness or readiness to react to a
particular sensory input.In other words, Attention allows us to process information about our
surroundings and the world we live in. To do this we select from competing
inputs and process the information we collect so we can understand it
better.
Our attention can quickly change from one thing to another,
although only a limited amount of information can be processed at any one
time, as our attention span has a limited capacity.Donald Broadbent in 1958 proposed one of the first models, based on
different information-processing tests and experiments. He did this in an
attempt to explain findings by Cherry in 1953. Cherry developed the
Dichotic listening task, in which the process of shadowing was observed.Broadbent advanced from these findings to develop the Split-span task.
I am
going to analyse this theory which involved using a selection filter for
his explanations and compare it to other researchers such as Treisman and
Moray.Broadbent in 1958 developed a task called the split-span task.And
these findings went on to help him develop a model of selective attention.This involved presenting the participant with two different inputs from two
different sources. I.e.
, one message relayed on one ear, whilsta
completely different one would be relayed in the other. The participants
were asked to report what they heard, without listening to a particular
ear. Broadbent proposed that our brain selects the channel of information
it wants to process and completely discards the other information. He
believed that people can only listen to one source at a time as there is
limited storage in our brain.
He also believed that the information we
receive travels in parallel to a short term storage space. This would keep
the information until it could be processed further and therefore extends
the period of stimulus.According to Broadbent's Filter Theory, the varioustypesof
information then travel to a selective filter, where the selection process
would begin of choosing which source would be processed further, and which
would be rejected. Broadbent said that this selection was done based on the
sources physical attributes. The model that Broadbent created for this was
in the shape of a Y. At the top of this Y were to input channels.
The two
pieces of information would travel down these two passages, until it became
just one stem and only one piece of information could go through at a time.Therefore signals arriving at the same time through different 'channels'
can't be processed concurrently, and therefore a 'bottleneck' is created.Broadbent stated that although it would be possible to switch from one
piece of information to the other, this would take time. E.
g., the
participant could report the message relayed into one ear, followed by
repeating the message relayed into the other ear. However this could prove
to be difficult as discussed earlier, the information is only held in an
auditory sensory store, and for this process to work, it would have to be
done in a short enough time for the information not to be diffused. This
means that the auditory store would have to retain the information for a
longer time, or else it would be lost before it was recognised. Broadbent's
theory can explain Cherry's findings, as the non shadowed message isn't
allowed to pass through the filter.
It can also explain the findings of the
split span tests, as the ear that the information travels through could be
the physical property of it.Although Broadbent's theory was influential, and provided a basis for
many researchers to develop further work on, it was incomplete.Gray and
Wedderburn in 1960 found Broadbent's model to be inadequate. They reported
from replications of the split span tasks findings that showed that meaning
played a part as well in the selection process. When two three word
sentences were split up, it was usual that the participant would remember
the meaningful sentence, even though parts of this sentence were relayed
through different ears.
Moray in 1959 discovered something called thecocktailparty
phenomenon. This is where typically at a party there are many different
conversations going on at any one time. One person would only be involved
in one conversation, but there would hear there name in a separate
conversation. The rest of the information would be filtered out, but their
name would pass though the filter. This shows Broadbent's theory to be
inadequate, as meaning obviously does play a part.
Another theory which yet again shows Broadbent's theory to be
inadequate is Triesman. Triesman developed a theory called the Attenuation
theory. This stated that is was obvious that some meaningful information
did get through the filter, however it maintained that Broadbent's theory
was also true to an extent that it was filtered on the basis of its
physical attributes first. This Attenuation Theory stated that instead of
information with inappropriate physical characteristics being filtered out,
it was simply weakened, or attenuated by the filter. Once information had
passed through the first filter, where it was either processes or weakened,
it would pass through a second- stage analyser, where it would be filtered
based on meaning.In conclusion, Broadbent's Filter Theory, was a very influential
Theory, and provided a strong base from which many researchers have
developed much more reliable models.
It was the first recorded filter
theory, and although it was flawed, and maybe incomplete, it still had
great use in society. It is partially supported by Triesman, and without
this base of knowledge, we have to ask whether Triesman would have found
these findings. Therefore, although Broadbent's theory in not of much use
in today's society, without it, the new research which is being ever
created would not have been possible.
References
Gross, R.
(2001). Psychology The Science of Mind and Behaviour- Fourth
Edition. Kent: Greengate
Hayes, N. (2000).
Foundation of Psychology:
Third Edition. London: Thomson Learning.
Reed, S. K. (1988). Cognition: Theory and Applications:
Second Edition.
California: Brooks/Cole
Solso, R. L. (2002). Cognitive Psychology:
Sixth Edition.
Allyn and Bacon