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You have just experienced what Broadbent and Cherry referred to as the “Cocktail Party
Phenomenon”. Part of consciousness is attention. We must attend to incoming stimuli in order to
process it and act on it in an appropriate manner. Does that imply that in the case presented above,
the listener was attending to the conversation behind her? Possibly, although the attention being
paid to that conversation was not intentional. The listener in this conversation was engaged in
what is known as dichotic listening, which refers to hearing two channels of sound, one in each
ear, at the same time. In dichotic listening, we listen, or shadow, the message to which we are
attending, and tune out the second, unattended message. Nonetheless, some characteristics of that
unshadowed message still get through. The individual above was shadowing the message in
which she was engaged and, until hearing her name, could not have told us the content or
characteristics of the unshadowed (unattended) message of conversation. How then, did she
manage to hear her name, if she was not attending to the message?
Triesman offers as an explanation the fact that in dichotic listening, attention acts as an attenuator,
in that it turns down the volume on unattended channels, but does not completely block them out.
Moray took this notion a bit further, observing that it is very difficult to ignore the sounds of our
own names, even if that sound comes in on an unattended channel. Deutsch and Deutsch, followed
by Norman, proposed that all channels that reach the system get some degree of attention and
analysis. Specifically, the channels get attended to enough to be represented in long-term memory.
While none of these models completely explains the attentional aspect of consciousness, they do at
least give us some insights as to why we suddenly find ourselves “eavesdropping” on the
conversations of others, once we have heard them mention our names.
Circadian Rhythms
There is a daily cycle in addition to sleep cycles that helps regulate our functioning. People and
other mammals have a biological clock that controls their daily rhythm, known as the circadian
rhythm. Bodily temperatures, endocrine secretions, metabolism, and other bodily functions follow
similar circadian rhythms. Both internal controls, from the hypothalamus in the brain, and external
controls such as clocks, meal times, light and dark, and the seasonal changes direct us to 24-hour
circadian rhythms. If individuals live in caves with artificial light, but no clock, eating and sleeping
whenever they want, circadian rhythms tend to occur in 25-hour cycles.
People usually fall into a rhythm between 24 and 28 hours long, although sleep—wake cycles of up
to 50 hours have been observed. Excessively long circadian rhythms can play havoc with one’s life,
causing one to be unable to sleep at an appropriate hour or to feel sleepy part of the normal working
day. The results can be job loss and interpersonal conflict. Such afflictions can be interpreted as
sleep-onset insomnia and/or excessive sleepiness. Treatment of such sleep disorders centers on
enforcing wakefulness at certain times.
Along with “autonomic” storms of REM sleep that are most intense in the morning hours, changes
in circadian rhythms result in a lowering of body temperature. One medical consequence of this
“vulnerable” state is the reported high incidence of cardiac failures and heart attacks in early
morning hours. “Jet lag” is also an effect of biological circadian rhythms falling out of synchrony
with local time as we travel east or west across time zones. The traveler develops a double circadian
rhythm, the new one added to the old. This leads to double peaks and valleys of energy. Over a few
days, the new circadian rhythm takes over as the body and brain reset their biological clock to local
time.
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CHAPTER 6: MIND, CONSCIOUSNESS, AND ALTERED STATES
The Stuff of Which Dreams Are Made
Throughout history, and probably prehistory as well, humans have thought that dreams have
special significance, that they have a divine source, predict future events, or prescribe a course of
action. A primary duty of wise elders in many cultures was to interpret dreams. One wonders how
preliterate tribes react to their dreams, to these images that invade their sleep. Perhaps they think
that some alien being has taken over their body or that they are receiving a message from the spirits
of the earth or the demons of the forest.
The idea that dreams have personal meaning was introduced in modern times by Freud when he
published The Interpretation of Dreams in 1900. Although it took six years to sell the first printing of
600 copies, it has become a classic. Freud argued that “dreams are impartial, spontaneous products
of the unconscious psyche, they show us the unvarnished truth.” Freud thought that the vigilance
of the ego relaxed during sleep, allowing primitive and forbidden sexual and aggressive urges to
escape from the unconscious. This material was so threatening to our waking state of
consciousness that the disgusting desires of the unconscious were disguised in dreams. It is
interesting to note that Freud, like Biblical characters and people of the past, thought that only a
wise man or woman (or psychoanalyst) could interpret dreams correctly.
Freud thought that there was a universal set of symbols used by the unconscious to disguise the
hidden content of dreams. For example, dreams of flying signify the desire for sexual adventure;
elongated objects such as trees and pencils symbolize the penis; containers, such as closets, rooms,
ovens, and automobiles represent the vagina; and sexual intercourse is disguised as riding a horse
or shooting a gun.
Carl Jung was a member of Freud’s inner circle, and later broke away from Freud because of
theoretical disagreements. He believed that the “general function of dreams is to restore
psychological balance,” and that important messages in dreams could only be interpreted from a
series of dreams that occurred over time. Jung estimated that he analyzed at least 80,000 dreams
during his professional career.
Anecdotal evidence to support Freud and Jung’s ideas about dreams exists, but their theories
cannot be experimentally supported or rejected because of problems in doing the necessary
research. Research on dreaming was stimulated in the early 1950s when two investigators,
Aserinsky and Kleitman at the University of Chicago, established the relationship between REM
sleep and dreaming, but their research does not answer the questions posed by the theories of Freud
and Jung. Some of the more frequently asked questions about dreams and dreaming follow.
DOES EVERYONE DREAM?