The new definition of working memory
In
his seminar work on the capacity differences of individual working
memory, Carpenter (Just & Carpenter, 1992) redefines its concept by
borrowing a computational theory. They posit that both information
restoring and processing are supported by the very same property named “Activation”.
When
we are taking in new information from computations, each element is
associated with an activation level. The element can be a word, sentence
or a physical object such as a cat.
During the comprehension,
only the element whose activation level exceeds the threshold value can
enter working memory; in other words, not all the candidates are able to
be further processed by brain even it is well retrieved from long-term
memory.
However, people differ from each other with respect to their work
memory capacity. In this case, which is seen as the total amount of
activation level that the system can sustain.
Therefore, if at one
time, the sum is about to go beyond the system limitation, certain
chunk of old information must be de-allocated in order to accommodate
more incoming data and computations.
Serving as one of fundamental concepts in cognitive science, we often find it in other literature.
Complementary learning systems
The
hippocampal (HC) systems will be active in receiving information and
temporally restoring the information, which means that the novel
material cannot be truly learned immediately.
The neocortical
systems will incorporate the new information gradually, as any quick
absorption could be detrimental to existing structures of knowledge.
The
novel input need to go through various consolidation stages to obtain a
membership from neocortical systems. Appropriate external events can
serve as good opportunities and will help adjust neocortical
connections.
Usually, the incorporation of unfamiliar material is
slow, especially for arbitrary and idiosyncratic materials. Thus, when
the memory traces degrade with time passing by, it is possible to lose
them before they can be built into the shared structures in neocortical
systems.
The complementary learning systems are more related to information storage and maintenance than information processing.
However,
the weight changes of neurological connections may also be bound with
“activation”. Without appropriate activations, the connections are not
re-constructed or even established.
Although McCelland (McCelland
& McNaughton, 1995) does not explicitly mention how the
incorporation rate is to do with working memory capacity, the concept of
“learning rate” may be a potential factor affected by the level of
activation.
Metaphor
Metaphor
in linguistic practices is fairly common, if a person wants to express
certain idea from utterances, the hearer often can detect the meaning
rather than the literal meaning of sentences.
If “S is P” actually refers to “S is R”,
the comparison theory attempts to address the question of “how can we
compute the potential value of R”; on the other hand, the interaction
theory tries to look into the range restriction for R’s value by
referencing the relationship between S and P.
To make this
communication possible, the speaker and hearer must have something in
common such as the principles to translate utterances.
Searles
provides eight principles and suggests the methods by which the
utterance of P term calls to mind the meaning of R term in the way
pertaining to metaphor. For example, one principle is about human
beings’ sensibility, and it is applicable for people from multiple
cultures, as it is naturally determined.
From the perspective of
working memory capacity, the duty to locate possible links between S and
P or narrow the scope of R values heavily rely on activation for each
property.
I maintain that the task to interpret metaphor is less
like to challenge us in that there are normally three base elements to
begin with, unless the range of R is quite large, or the “overlapping”
attributes of S and P are too many.
In fact, an interesting
question here is that: which principles consume more resources in
working memory. The seemly more complex principle is not necessarily the
one that requests a larger “brain”; it also depends on other constructs
such as hearer’s knowledge base related to a specific domain.
Categorical Perception
The
interplays between perceptual information and high-level knowledge of a
particular object are another universal cognitive process. There are
basically four rules that people use to group object.
While
prototypes allow us to bring in more attributes to formulate
semi-stereotypical representations, the exemplar models are stored
stably in the memory, and they appear in a highly-abstracted form.
The
process of establishing prototypes and exemplar sees the differences in
the light of McCelland’s theory on complementary learning systems.
Specifically, to build a new prototype may take a longer time than
modeling an exemplar, as the former has to undergo a systematic
procedure to live within existing structures that is shaped based on
other surviving prototypes.
From the standpoint of working memory, it should work well to predict the efficiency of categorizing a perceived object.
Nevertheless, it may not directly determine how soon the new token will reach neocortical systems.
In
the context of metaphor, in addition to referencing currently stored
categories for the purpose of producing the metaphorical meanings of the
utterance, we can also use the outcomes to re-categorize an object.
Cognitive Breakdowns
The
cognitive breakdowns appear in multiple forms; for example, the loss of
balance, the difficulty to focus, or the lack of reasoning
capabilities.
Working memory is one major component being
affected, for instance, some patients need to consistently re-chunk
information in order to continue searching for the answer to a simple
inquiry.
If the brain sees too much cognitive load, certain part
of it will cease functioning. From that perspective, a wise usage of
limited working memory resources is recommended for pertaining subjects.
The Representation of Personality in the Affective Reasoner
The situation is presented in frames, and frame matching asks for sufficient resources from working memory.
The
computations on situation frames are supposed to generate emotion.
Working memory is crucial for instantiating this intensive process on
left hemisphere (LHS).
The emotion is only available if over
intensity threshold, which is determined by bindings on LHS. Working
memory is attributable to the binding process.
Some Implications for Design
First, designers should realize that users have different ability to store and process information; thus they should not be self-centered as the solution provider.
Second, designers must avoid using a solution that is too novel; although it may surprise users for its creativity, it may damage existing usage patterns that the users hold for other tasks at that moment.
Third, providing a "buffer-zone" for chunking/rechunking is recommended, as well as “Recognize Rather Than Recall”. Methods such as those will reduce users’ cognitive load, thus decrement the chances of over-charging working memory.
Forth, metaphor is equally important in that it is relatively easier for users to figure out the underlying meaning of design elements such as button or a gesture.
Furthermore, the calling for “universal design” does not only apply to people with physical disabilities, but also patients with brain damages at various levels.
Last but not least, if by its definition, the title of “User Experience” caters to user’s emotion responses, designers are expected to understand a little bit about the principles of emotion generation.
Some Implications for Design
First, designers should realize that users have different ability to store and process information; thus they should not be self-centered as the solution provider.
Second, designers must avoid using a solution that is too novel; although it may surprise users for its creativity, it may damage existing usage patterns that the users hold for other tasks at that moment.
Third, providing a "buffer-zone" for chunking/rechunking is recommended, as well as “Recognize Rather Than Recall”. Methods such as those will reduce users’ cognitive load, thus decrement the chances of over-charging working memory.
Forth, metaphor is equally important in that it is relatively easier for users to figure out the underlying meaning of design elements such as button or a gesture.
Furthermore, the calling for “universal design” does not only apply to people with physical disabilities, but also patients with brain damages at various levels.
Last but not least, if by its definition, the title of “User Experience” caters to user’s emotion responses, designers are expected to understand a little bit about the principles of emotion generation.
(© 2012 Miaoqi Zhu)
