Transcript Chapter Two - Black Hawk College

Prologue to Chapter 3
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Fritz and Hitzig’s Prussian War brain
research on triagged soldiers
Legal controversies surrounding “brain
death”
The biological communications and control
centers are central to an understanding of
human behavior
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Nervous System: The biological
control center
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The nervous system is both a powerful
computer and a complex communications
system.
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There are multiple inputs to the system
The system conducts multiple internal
processes
There are multiple internal and external
outputs
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The Nervous System
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Neurons: the basic units of the nervous
system
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Parts of the neuron
Axon
 Dendrite
 Cell body or “soma”
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Neurons and synapse
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The Nervous System
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Neural transmission
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individual cells (neurons) transmit bioelectrical
energy along the length of the neuron
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electrolytes
action potential
resting potential
individual cells (neurons) transmit bioelectrical
energy between neurons at the synapse
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The Nervous System
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Synaptic transmission
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chemical substances transmit neural messages
across synapses (small spaces between
individual neurons)
receptor sites on dendrites
transmitter sites on synaptic knob
neural transmitters include acetylcholine,
serotonin, dopamine, epinephrine,
norepinephrine, endorphins, enkephalins
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Divisions of the nervous system
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Divisions of the central nervous system
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The Brain
The Spinal Cord
Divisions of the peripheral nervous system
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Somatic division of the peripheral nervous system
Autonomic division of the peripheral ner. sys.
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sympathetic nervous system
parasympathetic nervous system
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Structures and functions of the
brain
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Brain imaging techniques
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non-invasive techniques include the EEG,
CAT, PETT, and the MRI
EEG: Electroencephalograph
CAT: Computerized Axial Tomography
PETT: Positron Emission Transaxial
Tomography
MRI: Magnetic Resonance Imagery
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CAT Scan in progress
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Magnetic
Resonance
Imaging
(MRI)
through the
skull looking
at lower brain
and brain
stem
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Structures and functions of the
brain
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The hindbrain and midbrain: housekeeping and
reflex functions
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cerebellum: motor coordination and non-thoughtful
body movement and smooth movement
brain stem: responsible for maintenance functions,
e.g., heart beat, breathing
reticular activating system: in the brain stem,
regulates paying attention to new stimuli, waking,
sleeping, and daydreaming
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Anterior View of
Brain
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Lateral View: Right Hemisphere
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Structures and functions of the
brain
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Forebrain: cognition, motivation, and action
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Cerebral cortex: sensory, cognitive, and motor
functions
Hemispheres of the cerebral cortex
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right and left hemispheres
hemispheres connected by corpus callosum
some hemispheric functions are shared; some very different
functions occur in each hemisphere
Roger Sperry’s split brain research
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Structures and functions of the
brain
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Lobes of the cerebral cortex
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frontal lobes
parietal lobes
temporal lobes
occipital lobes
Specialized “cortices” in each of the four
lobes
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Transverse Section: Looking Right
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Cross - section looking
down from the top of
the brain
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Structures and functions of the
brain
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The Limbic System (on top of the brain stem) and
emotion
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Hypothalamus
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intimately involved in our motives and emotion
instructs the pituitary gland (master gland) to release
hormones
Thalamus
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primaryily a switching station for incoming/outgoing neural
messages
also involved in memory formation
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Limbic System
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Structures and functions of the
brain
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The brain is an interacting system
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though many separate parts, these parts work
together in intellectual and emotional
processing
inputs, internal processes, and outputs
identify the brain as a complex computer and
communications system
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Exploded View
of Brain
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Endocrine system
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The endocrine system entails chemical
messengers of the body consisting of a
number of glands that secrete hormones
into the bloodstream
The Pituitary Gland
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sometimes called the “master gland”
helps to regulate the activity of the other
glands in the endocrine system
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Endocrine system
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The Adrenal Glands
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play an important role in emotional arousal,
metabolism, and sexualarousal/functioning
located in the back on top of the kidneys
Islets of Langerhans
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located in the pancreas
regulates blood sugar levels by means of secreting
both glucagon and insulin
diabetes, hypoglycemia, and mood changes
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Endocrine system
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Gonads
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gonads produce sex cells (sperm, egg) and secrete
sex hormones
male: testosterone and androgens
female: estrogen and progesterone
Thyroid gland
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regulates metabolism and growth via hormone called
thyroxin located in the neck
Cretinism and iodinized salts
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Endocrine system
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Parathyroid gland
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helps to control excitability of nervous system by
secreting parathormone
similar to a “squelch” on a radio only this is in the
nervous system
Pineal gland
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located in the brain, secrets hormone called
melatonin, regulates sleep/wake cycles
melatonin associated with prolonged life in rats
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Genetic influences on behavior
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What is inherited?
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the influence of genes and environment on behavior
psychologists try to determine what are the genetic
and what are the environmental influences on
behavior
evidence suggests schizophrenia, antisocial behavior,
and manic depression may be of genetic origin
Implications of genetic behaviors?
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Genetic influences on behavior
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Biological mechanisms of inheritance: the
genetic code
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inheritance operates through genes found in
the nuclei of human cells
Genes and chromosomes
What is DNA?
 What is a gene?
 What is a chromosome?
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Segment of DNA
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Genetic influences on behavior
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Biological mechanisms of inheritance
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Dominant and recessive traits
dominant genes reveal their traits in the phenotype
whenever the gene is present
 recessive genes may or may not reveal their traits
in the phenotype depending on whether there is a
single or double recessive gene for a given trait
 eye color, hair color, finger length, etc. are
determined by dominant/recessive genes
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Genetic influences on behavior
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Biological mechanisms of inheritance
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Sex-linked genetic traits
operate according to what is and what is not
present genetically on the 23rd chromosomal pair.
In females this is the XX and, in males, the XY
chromosomal pattern
 males are more likely to have sex-linked genetic
defects (1 in 20); females not (1 in 1000)
 examples include hemophilia, male pattern
baldness, muscular dystrophy, etc.
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Genetic influences on behavior
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Biological mechanisms of inheritance
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Polygenetic inheritance: many genes having
an effect on one single trait, e.g., intelligence
Pleiotropic inheritance: one gene affecting
many traits, e.g., Down’s Syndrome
Chromosomal abnormalities
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e.g., Kleinfelter’s syndrome, Turner’s syndrome,
and XYY (supermale) syndrome
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Research on inheritance in
humans
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Studies of twins
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monozygotic vs dizygotic twins and inheritance
using different types of twins to determine genetic vs
environmental effects on behavior and traits
Adoption studies
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monozygotic twins separated at birth allow for
determination of environmental effects
reveal genes have strong behavioral influences
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Research on inheritance in
humans
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Role of inheritance in personality and
abnormal behavior
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concordance studies show that about 80%
probability exists if one monozygotic twin
develops schizophrenia that the other will
also
both normal and abnormal aspects of
personality are influenced by inheritance
e.g., alcoholism, drug abuse, risk-taking
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Applications of psychology
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Alzheimer’s disease caused by severe
atrophy of brain; results in slow but
progressive loss of personality and
intellectual functioning
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Acetylcholine deficiencies and Alzheimer’s
disease
Neural transmission and disease processes
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Applications of psychology
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Schizophrenia research
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Dopamine excesses and schizophrenia
L-DOPA, Parkinson’s Disease, and
schizophrenia
Excessive dopamine receptor sites in the
brain in some schizophrenic persons
Pharmacology and mental illnesses
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Applications of psychology
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Pharmacology, abnormal behavior, and the
future of treatment of mental disorders
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within a century it is likely that there will be
very little abnormal behavior due to
neurotransmitter/receptor aberations
pharmacological advancements suggest that
moods, thoughts, and even learning can be
influenced by various drugs
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Questions?
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Any questions on chapter 3?
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