So far, we have described
a model for human-human interaction, how it works and how it can be explained.
Our goal is to fit the technology of choice (i.e. the agent) to the user,
with the performance of the whole system (and not only single aspects of it)
as criterion for the adequacy for the fit. Understanding and conceptualising
such a total system, designing the environment and person-machine interface
for the desired performance is the concern of Ergonomics, “in order to make
them compatible with the needs, abilities and limitations of people” (International
Ergonomics Association 2000).
Cognition is the
field of psychology that is concerned with what we know, how we achieved this
knowledge, and how we make use of it to accomplish our goals. Cognitive
activities include intending, perceiving, attending, planning, controlling,
problem solving, deciding, remembering, and learning.
Bringing cognition
into ergonomics yields in Cognitive Ergonomics that “is concerned with the role
of cognition in the functioning of a system that involves the interactions of
people and technology, including the support that technology can provide to aid
the performance of the cognitive task” (Owen 2003). Ultimate goal is to design systems that
match the intentional, perceptual, conceptual, memorial, and decision making
capabilities of the users. Examples are the design and evaluation of decision
aids, instruction manuals, computer menus and displays.
In classic
psychology properties of the individual are taken as the unit of analysis, i.e.
what must be taken into consideration to identify and study a problem? Today’s
psychology distinguishes between the study of behaviour and study of the mind –
physical focus vs. mental focus. When psychology addresses ergonomics this
distinction is applied accordingly – physical ergonomics vs. cognitive
ergonomics. The latter analyses mental processes and mental structures and
takes the brain as unit of analysis. Today cognitive ergonomics “is focused
specifically on designing systems that accommodate the information-processing
capabilities of the brain” (Wickens and Holland 2000). It includes analysis of
mental processes and mental structures and takes the brain as the unit of
analysis.
Complementing this
basis, the model of total systems assumes that “psychological phenomena cannot
be explained in terms of psychological activities alone, for example,
attending, learning, thinking – that is, by mental events of processes with
brain locus.” (Owen 2003). Researchers must understand and take in
account the context, i.e. what the motivation is and what the person is
intending to achieve or avoid in that environment and situation. “In attempting
to optimise environments, equipment, and information, cognitive ergonomists
need to consider the person and environment (i.e. the ecosystem) as the unit of
analysis” (Owen 2003). The individual cognitive task is supported
by information technology to perform best.
Consequently ergonomics
have shifted away from the concept of constraining the human by procedures
and automation to exclude him as the weakest and most error-prone component
in the system. Today human expertise and flexibility are more valued. The
user isn’t obliged to adapt to technology anymore, but technology is adapted
to what is natural for the user. Then, if the computer affords a natural control
system part of the interaction skill is embedded in technology. As the basic
term in this thinking is ‘natural interaction’, we have do develop criteria
for determining what is natural interaction.