|
Home
>
User Design > Cognitive Processes
Understanding Basic Cognitive Processes
As a
technical documentation writer, it is advantageous to think about how
the maintenance technician is processing the information provided in the
manual. All humans process information in basically the same way,
and there are five primary themes which are consistent in our human
cognitive processes (Matlin, 2002). These themes are valuable when
considering human behavior in a user-centered design process to help you
understand how the user makes decisions, why errors may occur, and what
information may help prevent errors.
Table
of Contents
Theme 1:
The cognitive processes are active, rather than
passive.
Theme 2:
The cognitive processes are remarkably efficient and accurate.
Theme 3:
The cognitive processes handle positive information
better than negative information.
Theme 4: The
cognitive processes are interrelated with one another; they do not
operate in isolation.
Theme 5: Many cognitive processes rely on both
‘bottom-up’ and ‘top-down’ processing.
Theme 1:
The cognitive processes are active, rather than passive.
People are
continually seeking out information and actively drawing inferences which
were never directly stated. Our memory is not a passive storage system,
but rather an active process that searches and integrates information from
previous experiences and the present.
As previously
discussed using the Norman action cycle framework, the manual’s user may
draw inferences when too little information is explicitly stated or the
language is unclear to the user. There are also differences between users
in the levels and types of their own experience. Therefore, it is
advisable to provide sufficient information for the most novice user of
the manual.
Back to Top
Theme 2:
The cognitive processes are remarkably efficient and accurate.
When humans make mistakes it can often be traced to the use of a rational
strategy. When there is a lack of information on which to base a
decision, people frequently base their decisions on past experiences that
quickly come to mind. This is often a successful strategy but can also
lead to a mistake.
Another example of the efficiency of cognitive processes is the limitation
of human information processing. Humans can only hold information we are
presented for a brief period – approximately 7 +/- 2 chunks of information
– for 30 seconds or less unless it is repeated (Miller, 1956). Although
this can be frustrating in losing information quickly, it is this
efficiency which allows us to unclutter our memory with useful facts.
Writers of technical documentation should also take into consideration
these human capabilities and limitations. The more mental resources that
reading the documentation uses, the less a user has available to perform
the required actions. As the user reads the task’s steps, errors may
occur if too much information is presented. Writers may want to keep the
number of steps in the task to a minimum. More than seven procedural
steps can create problems for users. Having to re-read the task several
times to retain the correct procedure can be frustrating, confusing, and
lead to missing critical information within a step.
As
previously discussed, the user will ‘workaround’ the procedure as written
if it does not provide the necessary information or a logical sequence in
which to plan their actions or evaluate the outcomes. The manual’s users
are trying to complete the maintenance task and in all likelihood have an
idea of how the task should be performed. The more closely the task
matches the idea of the user’s plan of action, the more likely the task
will be performed as written. In the absence of applicable information in
the documentation, their decisions will likely be based on their previous
experiences which may lead to judgment errors.
Back to Top
Theme 3:
The cognitive processes handle positive information better than
negative information.
We
understand sentences better if they are worded in the affirmative.
Reasoning tasks are also easier with positive than with negative
information – our cognitive processes are designed to handle what is,
rather than what is not.
The
user will search for available information, especially when there is a
discrepancy in ‘what is’ and ‘what the technician thinks should be’,
either from the environment or from the maintenance manual. By creating
documentation that is orderly, logical, and consistent you “train” the
user as to what information is available and where to find the information
they need. Also, technical writers need to have consistency in language
by using the same vocabulary for the same purpose throughout the
documentation. Not just for a single writer, but for all writers working
on the same manual.
This theme also applies to the technical writer and technician in that it
is difficult to detect was is not present. For the writer, it is not easy
to find what is missing when writing or proofing the documentation for the
manual. As well, it is hard for the technician to know when information
is missing until, as noted in Norman’s model, there are gulfs of execution
or evaluation.
Back to Top
Theme 4: The cognitive processes are
interrelated with one another; they do not operate in isolation.
Decision making requires perception, memory, general knowledge, and
language. Consequently, tasks such as problem solving, logical reasoning,
and decision making are remarkably complex.
Though an extremely complex process, it is remarkably adaptive. Humans are
extremely creative at finding explanations and meanings from partial
stimuli. It is this ability which can cause technicians to misinterpret
procedures in such a plausible way that it is difficult to discover the
error in their interpretation and subsequent action. It is this latter
case that is most problematic and may account for aviation accidents
attributed to maintenance error.
As
maintenance technicians are trying to move toward their goals, they
utilize all of these capacities to make decisions. This requires that the
technical writer consider how the task is perceived – Does it differ from
other aircraft they are most likely familiar with? Is it complex enough
that an illustration would communicate more clearly than text? Is the
language and terminology clear and consistent throughout the procedure?
The technician will draw upon all available external cues, i.e., the
aircraft and the manual, plus their internal knowledge and memory to make
judgments leading to a decision of how to proceed.
Back to Top
Theme 5: Many cognitive processes rely on both ‘bottom-up’ and ‘top-down’
processing.
Bottom-up processing
is the information we gather from our senses – see, hear, smell, touch.
Top-down processing is information we retrieve from our memory of
experiences (cognitive processes). We “recognize” information from our
senses, i.e. sensory system (bottom-up process) and we “recall”
information from our memory, i.e. cognitive system (top-down process).
Using illustrations
can provide an additional visual framework in which to relate complex text
information and aid retention of the procedure. In this way, the user is
utilizing ‘bottom-up” processing from their “visual” sensory system, to
combine with the user’s “memory” or cognitive system to make action
decisions.
Back to Top |
