Developmental psychology.pdf

Perception and Consciousness 153
back and forth, asking ourselves: "Which is it?" This result was obtained when subjects
touched a three-dimensional cube, thereby gaining assurance about which corner
was closest and which was most distant. The reversals immediately decreased, suggesting
that the influential factor was not fatigue but rather a proper understanding
of the environment (Shopland & Gregory, 1964).
Information Processing in Perception We should emphasize here that perception
is a highly integrated process, one in which the basic processes—selection, organization,
and interpretation—occur in interrelated fashion in most instances. Perception is not
only active but, more accurately, interactive. It is influenced on one side by the sensory
input and on the other side by memories and thoughts about the incoming stimulation.
Many cognitive psychologists today speak of information processing, stressing that
several sequential and interactive mental operations are involved in the ways that we
come to understand the world.
In the information-processing approach, these activities include three general
components: the intake and output of information, its storage, and appropriate operations
carried out on the stored and transmitted information. At this point we are considering
only the first of these, the intake of information. In later chapters on memory
and cognition we shall focus upon the storage and mental operations, respectively. The
point to be stressed is merely that human beings use information in an active and interpretive
manner. They seek information, often going beyond What is given in the
environment, making of it whatever they can from the present context, past experience,
and expectations for the future.
•I'U '
Principles of Grouping Since a pattern usually has several parts, the next problem
concerns how the parts are organized, and here the gestalt principles are relevant. The
term gestalt is a German word meaning shape or configuration, and the psychologists
who first enunciated these principles sometimes were called configurationalists. They
were also called holistic psychologists because their emphasis is upon the whole pattern
or whole situation. Psychologists with this viewpoint sometimes disparage analytical
or reductionistic investigations, in which it is assumed that complex events are to be
understood only by identifying the smaller components.
According to the principle of similarity, stimuli of similar shape, size, sound,
or color tend to be grouped together. When Victor overheard a conversation between
Itard and Madame Guerin, his guardian, the boy could identify the sounds made by
each of them by the similarity of each person's tones. When Itard wished to train Victor's
sense of touch, he put a mixture of chestnuts, acorns, pennies, and eventually
metal letters in the bottom of an opaque vase. The boy placed his arm in the vase and
was made to understand that he should bring forth all items of a similar shape, which
he eventually accomplished readily (Figure 6.6).
The principle of proximity refers to the tendency to perceive stimuli near one
another as belonging together. For example, ask a friend to listen while you tap twice
in rapid succession, wait an interval, and tap twice again. When asked how many taps
he or she has heard, your listener probably will report two pairs of taps, rather than
four altogether (Figure 6.7).
Again, these principles appear innate, but sometimes, when they are in conflict,
we must learn to solve the problem. Itard used such problems in teaching Victor
the alphabet, drawing upon the blackboard two equal circles, one in front of himself
and one facing Victor. At each of six or eight points upon the circumference of each
circle he wrote a different letter, and then within the circles he wrote the same letters
but placed them differently in the two instances. Next, Itard drew lines connecting
each letter on the circumference with its counterpart in the interior of his circle, and
then he requested that Victor do the same for his own circle. At first this was a challenging
task for the boy, who wanted to connect them on the basis of proximity, but
later he used the principle of similarity, no longer bothered by the different displacement
of the letters.
-f 4-
+ + 4- +
Figure 6.6
Grouping: Similarity. The signs are
viewed as five rows, not seven
columns, though the distances
between the rows and columns are
equal.
oo oo oo oo
ooo oo ooo
oooo oooo
Figure 6.7
Grouping: Proximity. The eight
circles in each row are seen as
forming groups of four, three, or two
depending on their "nearness to one
another.