The Perception - Artificial Human Sensors: Science and Applications - page 63

Psychologists distinguish between two types of processes in perception:
bottom-up and top-down processing. Bottom-up processing, is also known as
data-driven processing, because perception begins with the stimulus itself. On
the other hand, top-down processing refers to the use of contextual information
in pattern recognition, that is the beliefs, cognition and expectation in perception.
The top-down processing is also known as a conceptually-driven process, Eysenck
(1995) and emphasises importance of the information provided by the visual envi-
ronment in a perception process. These two lines in visual processing, comprises
the fact that huge amount of information is collected by the eye, but most of the
data disappears by the time it reaches consciousness in the brain. Norretranders
(1998), estimates that about 90% of information is considered as not prioritised data
and therefore not considered in the continuous process. Therefore, the brain has to
conclude a person's momentary visual perceptual impression input, and added on
past experience and knowledge in the sense that a person's actively build his/her
perception of reality. The individual's perceptions of the world are obviously real
time sensing inputs, that are aggregated with subjective hypotheses based on past
experiences and stored information. Sensory receptors receive information from
the environment, which is then transported and further combined, with previously
stored information about the world, which the person has built up as a result of
earlier experiences. The formation of incorrect hypotheses, as well as incorrect sen-
sory perception will lead to distortion and provide a degree of acuity of perceiving
the world, e.g. the visual sensation.
A major theoretical issue on which psychologists are divided is the extent
to which perception relies directly on the information present in the stimulus.
Some argue that perceptual processes are not direct, but depend on the perceiver's
expectations and previous knowledge, as well as the information available in the
stimulus itself. This controversy is discussed with respect to the degree of involve-
ment of the perceiver's earlier experiences and previous knowledge.
The expected conclusion so far would seem to confirm that indeed we do
interpret the information that we receive, in other words, perception seems to
exhibit features of both data and conceptual drive processes. However, the
influence and balance of involvement by internal brain correction may be related
to the individual's momentary situation, e.g., similar experience, mood, stress, etc.
This mode of sensing ability may also vary in a manner that is not even foreseen,
when creating the discriminating human being as illustrated in Fig. 3.6.
3.2.2.1 HUMAN EMOTION
Following the statements of Damasio, (1999), then the expression;
feelings
in its definite form is reserved to our private emotions or mental experience of
a perception. In practical terms, this means that no one can observe or identify
the feeling of another person but on the other hand we can be wide open and
anyone can observe our feelings when we perceive the state of our emotional feel-