Introduction to Psychology, 7th Edition, Rod Plotnik
Module 4: Incredible Nervous System
Module 4
Incredible Nervous System
Introduction to Psychology, 7th Edition, Rod Plotnik
Module 4: Incredible Nervous System
GENES & EVOLUTION
• Genetic information
– brain and body developed according to complex
chemical instructions that were written in a human
cell no larger than a grain of sand
• Fertilization
• Zygote
• Chromosomes
• Chemical alphabet
• Genes and proteins
• Genome
• Genetic factors
Introduction to Psychology, 7th Edition, Rod Plotnik
Module 4: Incredible Nervous System
GENES & EVOLUTION (CONT.)
• Fertilization
– human life has its beginnings when a father’s
sperm, which contains 23 chromosomes,
penetrates a mother’s egg, which contains 23
chromosomes
Introduction to Psychology, 7th Edition, Rod Plotnik
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p68 SPERM EGG ZYGOTE
Introduction to Psychology, 7th Edition, Rod Plotnik
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GENES & EVOLUTION (CONT.)
• Zygote
– the largest human cell, about the size of a grain of
sand
– a zygote is a cell that results when an egg is
fertilized
– a zygote contains 46 chromosomes arranged in
23 pairs
Introduction to Psychology, 7th Edition, Rod Plotnik
Module 4: Incredible Nervous System
GENES & EVOLUTION (CONT.)
• Chromosomes
– a short, rodlike, microscopic structure that
contains a tightly coiled strand of the chemical
DNA, which is an abbreviation for
deoxyribonucleic acid
Introduction to Psychology, 7th Edition, Rod Plotnik
Module 4: Incredible Nervous System
GENES & EVOLUTION (CONT.)
• Chemical alphabet
– each chromosome contains a long, coiled strand
of DNA, which resembles a ladder that has been
twisted over an over upon itself
– each rung of the DNA ladder is made up of four
chemicals
– the order in which the four different chemicals
combine to form rungs creates a microscopic
alphabet
Introduction to Psychology, 7th Edition, Rod Plotnik
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p68 DNA
Introduction to Psychology, 7th Edition, Rod Plotnik
Module 4: Incredible Nervous System
GENES & EVOLUTION (CONT.)
• Genes and proteins
– Gene
– a specific segment on the long strand of DNA that
contains instructions for making proteins
– Proteins
– chemical building blocks from which all the parts
of the brain and body are constructed
Introduction to Psychology, 7th Edition, Rod Plotnik
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p68 CHROMOSOME
Introduction to Psychology, 7th Edition, Rod Plotnik
Module 4: Incredible Nervous System
GENES & EVOLUTION (CONT.)
• Genome
– The Human Genome Project
– began in 1995 and cost over $2.7 billion
– reached its first goal in 2003 of mapping all the
human
genes
– researchers found only about 30,000 human
genes instead of the estimated 100,000
Introduction to Psychology, 7th Edition, Rod Plotnik
Module 4: Incredible Nervous System
GENES & EVOLUTION (CONT.)
• Genetic factors
– researchers are discovering how genetic factors
interact with the environment to result in the
development of mental retardation, emotional and
personality traits, mental disorders, and various
cognitive abilities
• Fragile X syndrome
– an inherited developmental disability, is due to a
defect in the X chromosome
Introduction to Psychology, 7th Edition, Rod Plotnik
Module 4: Incredible Nervous System
GENES & EVOLUTION (CONT.)
• Evolution of the human brain
– 1859 Charles Darwin published the Origin of
Species
• Theory of Evolution
– says that different species arose from a common
ancestor and that those species that survived
were best adapted to meet the demands of their
environment
Introduction to Psychology, 7th Edition, Rod Plotnik
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p69 SKULL SIZE
Introduction to Psychology, 7th Edition, Rod Plotnik
Module 4: Incredible Nervous System
STUDYING THE LIVING BRAIN
• Brain scans
– techniques that can look through the thick skull
and picture the brain with astonishingly clarity yet
cause no damage to the extremely delicate brain
cells
– MRI and fMRI
Introduction to Psychology, 7th Edition, Rod Plotnik
Module 4: Incredible Nervous System
STUDYING THE LIVING BRAIN (CONT.)
• MRI
– magnetic resonance imagery
– involves passing nonharmful radio frequencies
through the brain
• fMRI
– functional magnetic resonance imaging
– measures the activity of specific neurons that are
functioning during cognitive tasks, such as
thinking, listening
Introduction to Psychology, 7th Edition, Rod Plotnik
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p70 MRI
Introduction to Psychology, 7th Edition, Rod Plotnik
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STUDYING THE LIVING BRAIN (CONT.)
• Brain scans and Cognitive Neuroscience
– PET scan
– positron emission tomography
– involves injecting a slightly radioactive solution
into the blood and then measuring the amount of
radiation absorbed by brain cells called neurons
Introduction to Psychology, 7th Edition, Rod Plotnik
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p71 PET
Introduction to Psychology, 7th Edition, Rod Plotnik
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STUDYING THE LIVING BRAIN (CONT.)
• Tools versus Animals
– naming animals
– naming tools
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p71 THINK OF ANIMALS BRAIN
Introduction to Psychology, 7th Edition, Rod Plotnik
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p71 THINKING OF TOOLS BRAIN
Introduction to Psychology, 7th Edition, Rod Plotnik
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ORGANIZATION OF THE BRAIN
• Divisions of the Nervous System
• Major divisions of the nervous system
– central nervous system - CNS
– peripheral nervous system - PNS
Introduction to Psychology, 7th Edition, Rod Plotnik
Module 4: Incredible Nervous System
ORGANIZATION OF THE BRAIN (CONT.)
• Central nervous system - CNS
– made up of the brain and spinal cord
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p72 CNS
Introduction to Psychology, 7th Edition, Rod Plotnik
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ORGANIZATION OF THE BRAIN (CONT.)
• Peripheral nervous system - PNS
– includes all the nerves that extend from the spinal
cord and carry messages to and from various
muscles, glands, and sense organs located
throughout the body
• Subdivisions of the PNS
– somatic nervous system
– autonomic nervous system - ANS
– sympathetic division
– parasympathetic division
Introduction to Psychology, 7th Edition, Rod Plotnik
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p72 PNS
Introduction to Psychology, 7th Edition, Rod Plotnik
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ORGANIZATION OF THE BRAIN (CONT.)
• Somatic nervous system
– network of nerves that connect either to sensory
receptors or to muscles that you can move
voluntarily, such as muscles in your limbs, back,
neck, and chest
– nerves contain two kinds of fibers
• Afferent
– sensory fibers; carry information to the brain
• Efferent
– motor fibers; carry information from brain or
spinal cord to the muscles
Introduction to Psychology, 7th Edition, Rod Plotnik
Module 4: Incredible Nervous System
ORGANIZATION OF THE BRAIN (CONT.)
• Autonomic nervous system - ANS
– regulates heart rate, breathing, blood pressure,
digestion, hormone secretion, and other functions
• Sympathetic division
– triggered by threatening or challenging physical or
psychological stimuli, increases physiological
arousal and prepares the body for action
• Parasympathetic division
– returns the body to a calmer, relaxed state and is
involved in digestion
Introduction to Psychology, 7th Edition, Rod Plotnik
Module 4: Incredible Nervous System
ORGANIZATION OF THE BRAIN (CONT.)
• Major Parts of the Brain
– Forebrain
– Midbrain
– Hindbrain
• pons
• medulla
• cerebellum
Introduction to Psychology, 7th Edition, Rod Plotnik
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p73 SIDE VIEW OF BRAIN
Introduction to Psychology, 7th Edition, Rod Plotnik
Module 4: Incredible Nervous System
ORGANIZATION OF THE BRAIN (CONT.)
• Forebrain
– largest part of the brain
– has right and left sides called hemispheres
– hemispheres are responsible for a number of
functions, including learning and memory,
speaking and language, emotional responses,
experiencing sensations, initiating voluntary
movements, planning, and making decisions
Introduction to Psychology, 7th Edition, Rod Plotnik
Module 4: Incredible Nervous System
ORGANIZATION OF THE BRAIN (CONT.)
• Midbrain
– has a reward or pleasure center, which stimulated
by food, sex, money, music, looking at attractive
faces, and some drugs (cocaine)
– has areas for visual and auditory reflexes
– contains the reticular formation, which arouses the
forebrain so that it is ready to process information
from the senses
Introduction to Psychology, 7th Edition, Rod Plotnik
Module 4: Incredible Nervous System
ORGANIZATION OF THE BRAIN (CONT.)
• Hindbrain
– Has three distinct structures:
• Pons
• Medulla
• cerebellum
Introduction to Psychology, 7th Edition, Rod Plotnik
Module 4: Incredible Nervous System
ORGANIZATION OF THE BRAIN (CONT.)
• Pons
– functions as a bridge to interconnect messages
between the spinal cord and brain
• Medulla
– located on top of the spinal cord
– includes a group of cells that control vital reflexes,
such as respiration, heart rate, and blood pressure
• Cerebellum
– located in the very back and underneath the brain
– involved in coordinating motor movements but not
in initiating voluntary movements
Introduction to Psychology, 7th Edition, Rod Plotnik
Module 4: Incredible Nervous System
CONTROL CENTERS: FOUR LOBES
• Wrinkled cortex
– a thin layer of cells that essentially covers the
entire surface of the forebrain
Introduction to Psychology, 7th Edition, Rod Plotnik
Module 4: Incredible Nervous System
CONTROL CENTERS: FOUR LOBES (CONT.)
• Four lobes
– Frontal lobe
– Parietal lobe
– Occipital lobe
– Temporal lobe
Introduction to Psychology, 7th Edition, Rod Plotnik
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p74 FOUR LOBES
Introduction to Psychology, 7th Edition, Rod Plotnik
Module 4: Incredible Nervous System
CONTROL CENTERS: FOUR LOBES (CONT.)
• Frontal lobe
– involved with personality, emotions, and motor
behaviors
• Parietal lobe
– involved with perception and sensory experiences
• Occipital lobe
– involved with visual processing
• Temporal lobe
– involved with hearing and speaking
Introduction to Psychology, 7th Edition, Rod Plotnik
Module 4: Incredible Nervous System
CONTROL CENTERS: FOUR LOBES (CONT.)
• Frontal lobe: functions
– motor cortex
– narrow strip of cortex that is located on the back
edge of the frontal lobe and extends down its side
– involved in the initiation of all voluntary
movements
– right side controls left
– left side controls right
– organization and function of motor cortex
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p76 MOTOR CORTEX
Introduction to Psychology, 7th Edition, Rod Plotnik
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CONTROL CENTERS: FOUR LOBES (CONT.)
• Other functions of frontal lobe
– much knowledge of other frontal lobe functions
comes from individuals who had damage to that
area
– Phineas Gage
Introduction to Psychology, 7th Edition, Rod Plotnik
Module 4: Incredible Nervous System
CONTROL CENTERS: FOUR LOBES (CONT.)
• Parietal lobe: function
– location of somatosensory cortex
– narrow strip of cortex that is located on the front
edge of the parietal lobe and extends down its
side
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p77 SENSORY HOMUNCULUS
Introduction to Psychology, 7th Edition, Rod Plotnik
Module 4: Incredible Nervous System
CONTROL CENTERS: FOUR LOBES (CONT.)
• Other functions of parietal lobe
– involved in several cognitive functions, including
recognizing objects, remembering items, and
perceiving and analyzing objects in space
Introduction to Psychology, 7th Edition, Rod Plotnik
Module 4: Incredible Nervous System
CONTROL CENTERS: FOUR LOBES (CONT.)
• Temporal lobe: functions
– primary auditory cortex
– located on top edge of each temporal lobe,
receives electrical signals from receptors in the
ears and transforms these signals into meaningful
sound sensations, such as vowels and
consonants
Introduction to Psychology, 7th Edition, Rod Plotnik
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p78 TEMPORAL LOBE
Introduction to Psychology, 7th Edition, Rod Plotnik
Module 4: Incredible Nervous System
CONTROL CENTERS: FOUR LOBES (CONT.)
• Temporal lobe: functions
– auditory association area
– located directly below the primary auditory cortex
– transforms basic sensory information, such as
noises or sounds, into recognizable auditory
information, such as words or music
Introduction to Psychology, 7th Edition, Rod Plotnik
Module 4: Incredible Nervous System
CONTROL CENTERS: FOUR LOBES (CONT.)
• Temporal lobe: functions
– Broca’s area - frontal lobe
• located in left frontal lobe
• necessary for combining sounds into words and
arranging words into meaningful sentences
– Wernicke’s area
• located in the left temporal lobe
• necessary for speaking in coherent sentences
and for understanding speech
Introduction to Psychology, 7th Edition, Rod Plotnik
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p78 BROCA’S WERNIKE’S
Introduction to Psychology, 7th Edition, Rod Plotnik
Module 4: Incredible Nervous System
CONTROL CENTERS: FOUR LOBES (CONT.)
• Occipital lobe: functions
– vision
– primary visual cortex
– located at the very back of the occipital lobe
– receives electrical signals from receptors in the
eyes and transforms these signals into
meaningless basic visual sensations, such as
lights, lines, shadows, colors, and textures
Introduction to Psychology, 7th Edition, Rod Plotnik
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p79 OCCIPITAL LOBE
Introduction to Psychology, 7th Edition, Rod Plotnik
Module 4: Incredible Nervous System
CONTROL CENTERS: FOUR LOBES (CONT.)
• Occipital lobe: functions
– visual association area
– transforms basic sensations, such as lights, lines,
colors, and textures, into complete, meaningful
visual perceptions, such as persons, objects, or
animals
Introduction to Psychology, 7th Edition, Rod Plotnik
Module 4: Incredible Nervous System
LIMBIC SYSTEM: OLD BRAIN
• Structures and functions
– Hypothalamus
– Amygdala
– Thalamus
– Hippocampus
Introduction to Psychology, 7th Edition, Rod Plotnik
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p80 LIMBIC SYSTEM
Introduction to Psychology, 7th Edition, Rod Plotnik
Module 4: Incredible Nervous System
LIMBIC SYSTEM: OLD BRAIN (CONT.)
• Hypothalamus
– regulates many motivational behaviors, including
eating, drinking, and sexual responses; emotional
behaviors such as arousing the body when
fighting or fleeing, and secretion of hormones,
such as occurs at puberty
• Amygdala
– located in the tip of the temporal lobe
– receives input from all the senses
– evaluates the emotional significance of stimuli and
facial expressions, especially those involving fear,
distress, or threat
Introduction to Psychology, 7th Edition, Rod Plotnik
Module 4: Incredible Nervous System
LIMBIC SYSTEM: OLD BRAIN (CONT.)
• Thalamus
– gathers and processes information from the
senses
– involved in receiving sensory information, doing
some initial processing, and then relaying the
sensory information to areas of the cortex
• Hippocampus
– curved structure inside the temporal lobe
– Involved in saving many kinds of fleeting
memories by putting them into permanent storage
in various parts of the brain
Introduction to Psychology, 7th Edition, Rod Plotnik
Module 4: Incredible Nervous System
LIMBIC SYSTEM: OLD BRAIN (CONT.)
• Autonomic nervous system
– Sympathetic
– Parasympathetic
Introduction to Psychology, 7th Edition, Rod Plotnik
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p81 SYMPATHETIC PARASYMPATHETIC
Introduction to Psychology, 7th Edition, Rod Plotnik
Module 4: Incredible Nervous System
LIMBIC SYSTEM: OLD BRAIN (CONT.)
• Autonomic nervous system
– Sympathetic
• triggered by threatening or challenging physical
or psychological stimuli
– Physiological responses
• increased heart rate, increased blood pressure,
and dilated pupils
• fight or flight
Introduction to Psychology, 7th Edition, Rod Plotnik
Module 4: Incredible Nervous System
LIMBIC SYSTEM: OLD BRAIN (CONT.)
• Autonomic nervous system
– Parasympathetic
• decreases physiological arousal
• returns the body to a calmer, more relaxed
state
• stimulates digestion during eating
– Physiological responses
• decreases heart rate
• lowers blood pressure
• stimulate digestion
• body returns to more relaxed state.
Introduction to Psychology, 7th Edition, Rod Plotnik
Module 4: Incredible Nervous System
LIMBIC SYSTEM: OLD BRAIN (CONT.)
• Autonomic nervous system
– Homeostasis
• sympathetic and parasympathetic systems
work together to keep the body’s level of
arousal in balance for optimum functioning
Introduction to Psychology, 7th Edition, Rod Plotnik
Module 4: Incredible Nervous System
ENOCRINE SYSTEM
• Endocrine System
– Made up of numerous glands that are located
throughout the body. Glands secrete various
chemicals called hormones.
• Pituitary
• Pancreas
• Thyroid
• Adrenal glands
• Gonads
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p82 ENDOCRINE SYSTEM
Introduction to Psychology, 7th Edition, Rod Plotnik
Module 4: Incredible Nervous System
ENOCRINE SYSTEM (CONT.)
• Pituitary gland
– hangs below the hypothalamus
– divided into anterior and posterior
• Posterior
– rear portion
– regulates water and salt balance
• Anterior
– front portion
– regulates growth through secretion of growth
hormone
– produces hormones that control the adrenal
cortex, pancreas, thyroid, and pancreas
Introduction to Psychology, 7th Edition, Rod Plotnik
Module 4: Incredible Nervous System
ENOCRINE SYSTEM (CONT.)
• Pancreas
– regulates the level of sugar in the bloodstream by
secreting insulin
• Thyroid
– located in the neck
– regulates metabolism through secretion of
hormones
Introduction to Psychology, 7th Edition, Rod Plotnik
Module 4: Incredible Nervous System
ENOCRINE SYSTEM (CONT.)
• Adrenal glands
– adrenal cortex (outside part)
– secretes hormones that regulate sugar and salt
balance
– adrenal medulla (inside part)
– secretes two hormones that arouse the body to
deal with stress and emergencies
– epinephrine (adrenaline)
– norepinephrine (noradrenaline)
Introduction to Psychology, 7th Edition, Rod Plotnik
Module 4: Incredible Nervous System
ENOCRINE SYSTEM (CONT.)
• Gonads
– Females
• ovaries produce hormones that regulate sexual
development, ovulation, and growth of sex
organs
– Males
• testes produce hormones that regulate sexual
development, production of sperm, and growth
of sex organs