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have yet to acplish to understand schizophrenia fully。
Program 8： States of Mind
Surveys the current state of our knowledge about the brain and what lies in the future。 Examines how this
knowledge will be applied in the ing years to the fields of medicine and artificial intelligence。
Decision （1985）。 IU （FFHS）； 27 minutes
Demonstrates how the brain organizes input and output to make simple but life…saving decisions。 Explains
how the cortex assesses ining information； sends outgoing messages to the muscles； and stores maps of
the world and the body。 Shows how circuits of nerve cells operate in the brain and how individual nerve
cells function。
Odyssey： Lucy and the First Family （1980）。 PBS； 59 minutes
The study of 3。5 million…year…old Lucy； one of the most plete human skeletons that has been discovered；
has led to a controversy regarding evolution。 This videotape provided a link between the field of
anthropology and the social sciences。
Our Talented Brain （1985）。 IU （FFHS）； 27 minutes
Explores the physiological brain capacity of human beings； their use of memory； and their use of symbols。
Explains how these capacities relate to the neural structure of the brain。
The Infinite Voyage： Fires of the Mind （1988）。 WQED and the National Academy of Sciences； 58 minutes
Covers the development of human intelligence； and how cells； electric signals； and chemicals make up the
creative mind of man。 Features a study of the cells of Einstein’s brain。
The Nervous System： Nerves at Work （1982）。 Salubris Productions （PBS）； 26 minutes
The electrochemical nature of neural transmission and neural action in reflexive behaviors is examined in
this film。
CASE STUDY LECTURE LAUNCHER
Five…and…a…half weeks before her twins were due； Christine felt the first sharp pains of labor。 Her husband
drove her to the hospital where； for 16 hours； the two of them followed the breathing instructions given to
them during their natural childbirth class。 Then a fetal monitor showed that the heartbeat of one of the
babies was weakening。 Doctors quickly performed a Cesarean section。 Within minutes； 4…pound Nicole and
3…pound 14…ounce Alexis entered the world。
Immediately after birth； Nicole and Alexis joined half a dozen other babies in the Neonatal Intensive Care
Unit。 For two…and…a…half weeks； electronic devices monitored their vital signs。 Experienced nurses tended to
their physical needs and held them frequently。 Christine spent a good part of each day with her babies；
holding and rocking them and feeding them her breast milk from bottles； awaiting the day when she could
50
CHAPTER3： THE BIOLOGICAL BASES OF BEHAVIOR
actually breast feed them。 Wearing diapers barely the size of cocktail napkins； the twins looked fragile and
unfinished。 With no layers of baby fat； every little rib showed。
Had Nicole and Alexis been born 20 years earlier； their first few weeks of life would have been quite
different。 Until the late 1970s； premature infants were touched as little as possible。 Parents and medical
personnel feared that any unnecessary contact with the outside world might harm the babies。 Fortunately
for Nicole and Alexis； we now know better。
Research with infant rats and humans has led scientists to conclude that brain functioning can be altered
by touch； and that； for newborns； touch is essential for normal growth and development。 Biologist Saul
Schanberg found that when rat pups were removed from their mothers； the levels of an enzyme important
for growth decreased dramatically。 The longer they were deprived of maternal contact； the less responsive
the pups became。 The effects of maternal deprivation could be reversed in only two ways： by returning them
to their mother； who immediately started to lick them； or by having a researcher vigorously stroke them with
a small paintbrush。 Shanberg concluded that； “the need for a mother’s touch is really brain based。 It is not
just nice to have it。 It’s a requirement for the normal development and growth of the baby。”
Psychologist Tiffany Field； who had collaborated with Schanberg； conducted similar stimulation studies of
premature human infants。 Her research team randomly selected 20 preemies to receive periodic massages
throughout the day； while 20 others received normal hospital treatment in the intensive care unit； treatment
that did not include massage。 According to Field； “The premature babies who were massaged for 45
minutes a day for ten days before they were discharged gained 47 percent more weight than the babies who
did not get massaged。 They were more active。 They were more alert。” Eight months later； the massaged
babies had maintained their weight advantage and were more advanced in motor； cognitive； and emotional
development。 This research is being extended and replicated in larger samples of preemies in order to
establish the power of human touch on biological and psychological health。
In the United States； more than 0。25 million infants are born prematurely each year。 Those who are touched
and cuddled leave the hospital several days sooner than usual； reducing care costs by about 3；000 per
child。 Unfortunately； not all hospitals apply what scientists have learned about the positive effects of early
touch on development。 If they did； the lives of thousands of children would be improved； saving billions of
dollars each year—both practical benefits of this basic research。
When Nicole and Alexis left the hospital； they were still small； but were developing so well that doctors felt
confident they would be all right。 At home； the babies shared a crib in the living room； where relatives and
friends who remarked on their tiny size were encouraged to pick up the babies gently and cuddle them。
Christine and her husband were acutely aware of the important role played by human touch in the optimal
development of the brain and the mental and psychical processes that it controls。
51
CHAPTER 4
Sensation
LEARNING OBJECTIVES
On pletion of this chapter； students should be able to：
1。 Understand the basic processes through which sensory stimuli are converted into neural
events
2。 Describe Müller’s doctrine of specific nerve energies
3。 Relate the differences in thresholds （absolute and difference） and know why these concepts
are relevant
4。 Discuss the concepts of response bias and signal detection theory
5。 Identify the parts and functions of the human visual system
6。 Understand the basic processes involved in color vision； and the theories supporting those
processes
7。 Describe the physiological ponents of the auditory system
8。 Explain the two theories of pitch perception
9。 Define pheromones and describe their role in olfaction
CHAPTER OUTLINE
I。 Sensory Knowledge of the World
A。 Sensation is the process by which stimulation of sensory receptors produces neural
impulses that represent experiences inside or outside the body
B。 This chapter deals with sensory processes； with the sense organs and peripheral aspects of
the nervous system that put you in contact with the world around yo