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Sensing and Responding to the Environment
Nerves allow us to perceive the environment
while the brain integrates the incoming signals
to determine an appropriate response.
CB 48.3
Neurons: cells specialized for
transmitting signals
CB 48.4
Neurons are commonly connected to many
other neurons, and the effect of the different
incoming signals determines what the neuron
will do.
CB 48.14
CB 49.4
The brain and the
central nervous
system integrate
the various
incoming signals
Different regions of the cerebral cortex
integrate different inputs/outputs
CB 49.15
Visualizing the specialization of brain regions
CB 49.17
Some body parts have more sensory input/
motor control
CB 49.16
Some responses are to subtle stimuli
CB 48.3
Circadian Rhythms: daily patterns set by light
(northern flying squirrel)
Today’s video about different human
reactions to cool:
http://www.youtube.com/watch?v=XHmM7gJhscU
"The Role of Dreams in
the Evolution of the
Human Mind" by
Michael Franklin and
Michael Zyphur in
Evolutionary Psychology
2005. 3: 59-78
http://humannature.com/ep/articles/ep
035978.html
Why do we dream?
Random Neural Activity or Rehearsal
Why do we dream?
Dreams are difficult to study because of their
subjectivity
Some are rational while others are
non-sensical
Is there an evolutionary explanation?
Were/are individuals that dream better at
passing on genes?
Why do we dream?
Is there an evolutionary explanation?
Most common in REM
Why do we dream?
Rehearsal, conscious practice activates and
exercises connections.
What about unconscious practice?
Why do we dream?
Common dream subjects are threats and social
interactions.
There is some randomness – randomness gives
broad variability of dreams and generates new
situations
Why do we dream?
Dreams as rehearsal for threats, social
situations, etc.
Practice, conscious and unconscious, can
improve performance, so might give
evolutionary advantage.
Nerves allow us to perceive the environment
while the brain integrates the incoming signals
to determine an appropriate response.
Fig 46.1
Response
Responses can be
release of hormones,
change in cell activity,
or muscle contraction
Sensing and Responding to the Environment