The Biological Basis for Behavior

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The Biological Basis for Behavior

• The Human Brain

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Bellringer 3

• List at least five things your brain does on a
  daily basis.

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I. Brain Basics

• A. Studying the brain
• 1. This area of the science of psychology is
  experiencing an explosion of research
• 2. This is mostly due to changes in technology
  that allow us to see the brain as it works.

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• B. Phrenology
• 1. A concept developed by a German Physician
  named Franz Gall.
• 2. The theory stated that bumps on the skull
  revealed our mental abilities and personality
  traits.

Phrenology
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• C. Basic Terminology
• 1. Biological psychologist a branch of
  psychology concerned with the links between
  biology and behavior.
• 2. Sometimes referred to as neuropsychology,
  neuroscience, physiological psychology, or
  biopsychology.
• 3. Neuroanatomy refers to the study of the parts
  and functions of neurons

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II. Neural anatomy and Neural Communication

• A. Neurons the basic building blocks of the
  brain
• electrically transmit data in your brain
• makeup 1/2 the volume of the brain

Neurons
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• B. Glial Cells support the neurons
• 1. may be 10 times as numerous as neurons
• 2. make up the other half of the volume of the
  brain

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• C. Neurons
• 1. Three types of Neurons
• a. Sensory neurons that carry incoming
  information from the sense receptors to the CNS
  also known as AFFERENT NEURONS.

Sensory Neuron
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• b. Motor the neurons that carry outgoing
  messages from the CNS to the muscles and glands.
  Also known as EFFERENT NEURONS.
• c. Interneurons CNS neurons that internally
  communicate and intervene between the sensory
  inputs and motor outputs

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Diagram of a Neuron
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• 2. The structure of the Neuron
• a. Dendrites the bushy, branching extensions
  of a neuron that receive messages and conduct
  impulses forward toward the cell body. Get its
  name from the Greek word for tree.
• b. Axon the extension of a neuron, ending in
  branching terminal fibers, through which messages
  are sent to other neurons or to muscles or glands
• c. The Soma the Cell body its function is to
  support the cell. At the center is the nucleus

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• d. The myelin sheath is a layer of fatty
  segmented tissue that encases the fibers of many
  neurons
• Enables vastly greater transmission speed of
  neural impulses as the impulse hops from one node
  to the next
• The Nodes of Ranvier the nodes along the myelin
  sheath
• e. The Synapse the junction between the axon
  tip of the sending neuron and the dendrite or
  cell body of the receiving neuron also called
  the synaptic gap or cleft

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The Synapse
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• f. The axon terminal or pre-synaptic terminal
  is the bulb at the end of an axon through which
  neurotransmitters are released. (AKA terminal
  buttons, end buttons, and synaptic knobs)
• g. Vesicles bubble like structures which
  contain the neurotransmitters

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• h. Neurotransmitters chemical messengers that
  transverse the synaptic gaps between neurons.
  They create or inhibit the receiving neuron form
  generating a neural impulse
• i. Synaptic receptor sites AKA binding sites
  each site is like a lock keyed to the particular
  chemical structure of each different type of
  neurotransmitter

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Neurotransmitters at work
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• 3. The Neuron at Rest
• a. Resting potential the interior cellular
  fluid of the axon has a slightly higher negative
  charge. This positive outside/negative inside
  polarization is called resting potential
• b. The cell membrane is selectively permeable
  that is it allows only certain ions in or out
• c. Sodium Potassium pump the resting cell
  continually pumps three sodium ions out while
  letting two potassium ions in Since both of
  these ions have a positive charge the result is a
  slight decrease in the positive charge of the
  inside of the cell

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Ion concentrations
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The Cell Membrane is Semi-Permeable
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• 4. The Action Potential
• a. Action potential a neural impulse
• i. A brief electrical charge that travels down
  an axon
• ii. The action potential is generated by the
  movement of positively charged sodium ions into
  the axon
• b. Thresholds the level of stimulation
  required to trigger a neural impulse
• c. The all-or-none law states the size,
  amplitude and velocity of an action potential are
  independent of the intensity of the stimulus that
  initiated it

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Resting Potential

• At rest the inside of the cell is at -70
  microvolts
• With inputs to dendrites inside becomes more
  positive
• if resting potential rises above threshold an
  action potential starts to travel from cell body
  down the axon
• Figure shows resting axon being approached by an
  AP

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Depolarization ahead of AP

• AP opens cell membrane to allow sodium (NA) in
• inside of cell rapidly becomes more positive than
  outside
• this depolarization travels down the axon as
  leading edge of the AP

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Repolarization follows

• After depolarization potassium (K) moves out
  restoring the inside to a negative voltage
• This is called repolarization
• The rapid depolarization and repolarization
  produce a pattern called a spike discharge

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• d. The refractory period is the time during
  which a neuron resists further action potentials
  while it recharges

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Bell Ringer 4

• How is a neuron firing like a toilet flushing?
  Be sure to include the following vocabulary in
  your explanation (underline each term).
• Resting Potential
• Threshold
• Action Potential
• All or none
• Depolarization
• Refractory Period

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III. Neurotransmitters

• A. Serotonin
• 1. Affects mood, hunger, sleep and arousal
• 2. Implicated in states of consciousness
• 3. Prozac and similar antidepressant drugs raise
  serotonin levels
• 4. LSD seems to act on this system

Serotonin
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• B. Dopamine
• 1. Influences movement, learning, attention and
  emotion
• 2. Excess activity at dopamine receptor sites is
  associated with schizophrenia
• 3. Too little activity is associated with
  Parkinsons
• C. Norepinephrine
• 1. Helps control alertness and arousal
• 2. Too little can lead to depression
• 3. Too much can lead to manic episodes

Dopamine Drugs
Norepinephrine
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• D. Acetycholine
• 1. Works on neurons involved in muscle action,
  learning and memory
• 2. The poison curare works by blocking ACh
• 3. Patients with Alzheimers show a
  deterioration in this chemical messenger
• E. GABA gamma aminobutyric acid
• 1. Serves inhibitory functions and is sometimes
  implicated in eating and sleeping disorders
• 2. Also implicated in anxiety
• 3. Works with valium by increasing GABA which
  decreases anxiety.

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• F. Glutamate
• 1. Is the main excitatory neurotransmitter in
  the brain
• 2. Some people have an adverse reaction to MSG
  (Monosodium Glutamate) in Chinese food, it tends
  to wind them up and make them feel anxious

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• F. Endorphins
• a. Natural pain killers in the brain
• b. Morphine is a synthetic endorphin
• c. Substance P is a neuro-cheimical that is
  still not fully understood but researchers
  suspect that it is involved in triggering the
  pain response

ENDORPHINS
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• G. How drugs and other chemicals Alter
  neurotransmission
• 1. Agonist work by mimicking a particular
  neurotransmitter or by blocking its reuptake (or
  absorption back into the body)
• 2. Antagonist work by blocking the release of
  particular neurotransmitters.

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The Nervous System

• A. The Central Nervous System
• 1. Also known as the CNS
• 2. It consist of the brain and the spinal cord
• 3. Cerebrospinal Fluid (CFS) is a a liquid
  similar to blood serum found in the ventricles of
  the brain and in the central canal of the spinal
  cord
• 4. The Blood-Brain Barrier is the mechanism that
  keeps many chemicals from crossing from the blood
  stream into the brain. This keeps most viruses
  out of our brain. Certain chemicals like drugs
  are disolved in fats and can cross the barrier.

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• B. The Peripheral Nervous System PNS
• 1. The sensory and motor neurons that connect
  the CNS to the rest of the body
• 2. It sends sensory input to the brain and
  relays commands from the brain to muscles

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• 3. Nerves neural cables containing many axons
  which connect the CNS with muscles, glands, and
  sense organs
• 4. The PNS consists of
• a. The Somatic System the division of the PNS
  that controls the bodys skeletal muscles AKA
  the skeletal nervous system

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• b. Autonomic System the part of the PNS that
  controls the glands and the muscles of the
  internal organs such as the heart.
• Sympathetic Nervous System the division of the
  ANS that arouses the body, mobilizing its energy
  in stressful situations
• Parasympathetic Nervous System the division of
  the ANS that calms the body, conserving its energy

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The Nervous System
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The Autonomic Nervous System

• Sympathetic Nervous System
• Dilates pupils
• Accelerates heartbeat
• Inhibits digestion
• Stimulates release of adrenaline, epinephrine and
  norepinephrine
• Releases the bladder

• Parasympathetic Nervous System
• Contracts pupils
• Slows heartbeat
• Stimulates digestion
• Contracts bladder

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• C. Reflexes and Neural Networks
• 1. Reflex is a simple, automatic, inborn
  response to a sensory stimulus, such as the
  knee-jerk response
• 2. A simple reflex pathway also known as a
  reflex arc is composed of a single sensory neuron
  and single motor neuron and sometimes an
  interneuron
• 3. An example of a simple reflex
• a. If you put your hand over a flame you will
  pull it back before you actually feel the pain
• b. Sensory neurons in your hand send info up
  your arm to interneurons located in your spine

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• c. From the interneurons to motor neurons
  causing your hand to pull back
• d. Finally the message will also travel up your
  spine to your brain where the feeling of pain
  will register

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• 4. Neural Networks
• a. Interconnected neural cells
• b. With experience, networks can learn, as
  feedback strengthens or inhibits connections that
  produce certain results.
• c. Computer simulations of neural networks show
  analogous learning

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Bell-ringer 4

• Write down these sentences then write down which
  nervous system would be in charge of each of
  these functions
• sending visual information to the brain
• Throwing a baseball
• your personality
• an increase in your heart rate during an
  emergency
• Thinking about your boyfriend or girlfriend
• Bringing the body back to its normal state.

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IV. The Endocrine System

• A. The bodys slow chemical communication
  system made up of a set of glands that secrete
  hormones into the bloodstream
• 1. Transmit hormones through the blood system as
  compared to the neural system
• 2. Slow, minutes or hours compared with
  fractions of seconds
• 3. Long lasting, versus short lived

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• B. Hormones chemical messengers mostly those
  manufactured by the endocrine glands, that are
  produced in one tissue and affect another.
• C. The Glands
• 1. The adrenal glands
• a. A pair of endocrine glands just above the
  kidneys
• b. The adrenals secrete the hormones epinephrine
  and norepinephrine (also known as adrenaline and
  noradrenaline)
• c. Helps to arouse the body in times of stress

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• 2. The Pituitary Gland
• a. The endocrine system's most influential gland.
  
• b. Once considered the master gland
• c. located at the base of the brain near the
  hypothalamus
• d. Under the influence of the hypothalamus the
  pituitary regulates growth and controls other
  endocrine glands

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• 3. Thyroid Gland
• a. H shaped gland located in the neck
• b. Affects metabolism
• 4. Parathyroids help regulate calcium in the
  blood stream which is important for
  neurotransmission
• 5. Pancreas regulates the level of sugar in
  the blood

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• 6. Types of hormones
• a. Progesterone a hormone that prepares the
  uterus for the implantation of an egg.
• b. Estrogen a hormone that is more prevalent
  in females
• c. Testosterone a hormone that is more
  prevalent in males
• d. Insulin a pancreatic hormone that
  facilitates the entry of glucose into the cells

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• e. Melatonin a hormone that is closely tied to
  sleep.
• f. Cortisol a hormone that is released by the
  adrenal glands which is associated with elevating
  blood sugar and with stress.
• g. Epinephrine is also known as adrenaline it is
  also used as a neurotransmitter
• h. Norepinephrine is a hormone that is also a
  neurotransmitter

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Bell-ringer

• Take out your diagram of the neuron and study for
  a quiz

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V. The Brain

• A. Tools of Discovery
• 1. Lesions and Accidents
• a. Tissue destruction. A brain lesion is a
  naturally or experimentally caused destruction of
  brain tissue
• b. Used to determine the impact on the brain
  functioning

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• 2. EEG
• a. Electroencephalogram
• b. An amplified recording of the waves of
  electrical activity that sweep across the brains
  surface. These waves are measured by electrodes
  placed on the scalp

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• 3. CT/CAT SCAN
• a. Computed Tomography
• b. A series of x-ray photos taken from different
  angles and combined by a computer into a
  composite representation of a slice through the
  brain or body
• 4. SPECT Scan
• a. Single Positron Emission Computed Tomography
• b. Inject a radioactive isotope into the blood
  and examine how the blood is moved in the brain.

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• 5. PET SCAN
• a. Positron Emission Tomography
• b. A visual display of brain activity that
  detects where a radioactive form of glucose goes
  while the brain performs a given task
• 6. MRI
• a. Magnetic Resonance Imaging
• b. A technique that uses magnetic fields and
  radio waves to produce computer-generated images
  that distinguish between different types of soft
  tissue
• c. Allows us to see structures within the brain

CBS special on MRI lie detection
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• 7. FMRI
• a. Functional MRI
• b. Similar to the MRI but pictures are taken
  less than a second apart
• c. The pictures reveal how much oxygen is being
  used in each area of the brain while functioning
• d. These pictures reveal when things happen, how
  the brain changes with experience and how
  different areas of the brain work together

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• 8. Recent findings using scanning technology
• a. PET scans show that the brain areas that
  light up when people silently say the name of a
  animal differs from when they say the name of a
  tool
• b. MRI scans of bilingual peoples brain reveal
  that second languages are represented in the same
  area as the first if learned early and in
  different areas if learned later.
• c. FMRI scans reveal that during a rhyming task
  mens brains have a distinctively active left
  brain area while womens brains are active on
  both sides

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• B. The basic organization
• 1. Reptilian - aka R-complex Brain
• a. Medulla, pons and cerebellum
• b. Homeostasis and instinctive behaviors
• 2. early mammalian
• a. Limbic system - hippocampus and the amygdala,
  the hypothalamus and the thalamus
• b. Affective and emotional behavior
• 3. late mammalian
• a. Cerebral cortext
• b. Judgement planning etc

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• C. The Central Core
• 1. The brain stem
• a. brainstem the oldest part and central core
  of the brain
• b. Begins where the spinal cord swells as it
  enters the skull
• c. The brainstem is responsible for automatic
  survival functions
• d. The hindbrain is the most posterior part of
  the brain it includes the medulla, Pons and
  cerebellum

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• 2. Medulla oblongata
• a. Medulla the base of the brainstem
• b. Controls heartbeat and breathing
• c. It lies directly on top of the spinal cord
• 3. Pons
• lies directly above the Medulla
• acts as a bridge between the Medulla and the rest
  of the brain, as well as between the cerebral
  cortex and the cerebellum
• 4. Reticular formation
• a. Reticular formation a nerve network in the
  brainstem that plays an important role in
  controlling arousal

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• b. Moruzzi and Magoun discovered that
  electrically stimulating the reticular formation
  of a sleeping cat almost instantly produces an
  awake and alert animal. They also severed the
  reticular formation and the cat went into a coma
• 5. The Midbrain located between the hindbrain
  and forebrain, it controls and coordinates some
  basic sensory and muscle movements.

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• 6. The Thalamus
• a. The thalamus the brains sensory
  switchboard
• b. Located on top of the brainstem located in
  both hemispheres resembling twin avocados
• c. It directs messages to the sensory receiving
  areas of the cortex and transmits replies to the
  cerebellum and medulla
• 7. Cerebellum
• a. The little brain attached to the rear of
  the brain stem, to the side of the pons and
  medulla
• b. It helps to coordinate voluntary movement and
  balance

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• D. The Limbic System
• 1. Sometimes referred to as the forebrain
• 2. The limbic system
• a. a doughnut shaped system of neural structures
  at the border of the brainstem and the cerebra
  hemispheres
• b. Associated with emotions such as fear and
  aggression and drives such as those for food and
  sex
• c. Includes the hippocampus, the amygdala, and
  the hypothalamus

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• 2. The amygdala
• a. Two almond shaped neural clusters that are
  components of the limbic system and are linked to
  emotion
• b. Research on aggression
• Lesions on the amygdala of an ill-tempered monkey
  turned him docile (Bucy 1939)
• Stimulate one section of a cats amygdala and it
  prepares to attack, stimulate another area and
  put it in a cage with a mouse and it cowers in
  terror
• Has been tried on human patients with mixed and
  sometimes devastating results

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• 3. The Hippocampus
• a. From the Latin word meaning seahorse
• b. Lies between the thalamus and the cerebral
  cortex
• . Is linked with forming new memories
• 4. The Hypothalamus
• a. A neural structure lying below (hypo) the
  thalamus.
• b. It directs several maintenance activities
  (eating, drinking and body temp), it helps govern
  the endocrine system via the pituitary gland and
  it is linked to emotion

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• c. Olds and Milner
• While trying to implant electrodes in the
  reticular formation of white rats they mistakenly
  implanted the electrode in a region of the
  hypothalamus
• The rat kept returning to the place in his cage
  where he received the electrical stimulation
• They had discovered a reward center in the
  hypothalamus

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• The rats would do anything to get this
  stimulation, including crossing an electrified
  floor. They would push the button to get the
  stimulation up to 700 times per hour
• Similar reward centers have been found in many
  other animals such as goldfish, dolphins and
  monkeys
• When an electrode was planted in violent patients
  they reported mild pleasure but were not driven
  to frenzy like the rats
• Reward deficiency syndrome is genetic disposed
  deficiency in the natural brain systems for
  pleasure and may lead to such disorders as
  alcohol and drug abuse

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Olds and Milner Study
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• E. The Cerebral Cortex
• 1. Physical description
• a. Convolutions increase the surface area of the
  brain
• b. Gyri rolls that form the folding out
  portion
• c. Sulci valleys
• d. Fissures are deeper than valleys

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The Cerebral Cortex
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• 2. The four lobes
• a. Frontal lobes
• The portion of the cerebral cortex lying just
  behind the forehead
• Involved in speaking and muscle movements and in
  making plans and judgments
• prefrontal cortex receives sensory information
  from all senses
• b. Occipital lobes
• The portion of the cerebral cortex lying at the
  back of the head
• Includes the visual areas, (V1 V2) which
  receive visual information from the opposite
  visual field
• cortical blindness is a specific type of
  blindness due to brain damage

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• c. Parietal lobes
• The portion of the cerebral cortex lying at the
  top of the head and toward the rear
• Includes the sensory cortex
• specializes in processing body information such
  as touch and body location
• d. Temporal lobes
• The portion of the cerebral cortex lying roughly
  above the ears
• Includes the auditory areas, each of which
  receives auditory information primarily from the
  opposite ear.
• One of the key areas of speech known as
  Wernickes Area is located in this lobe

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• 3. Motor Functions
• a. The motor cortex an area at the rear of
  the frontal lobes that controls voluntary
  movement
• b. Foerster and Penfield mapped the motor
  cortexes of wide awake patients by electrically
  stimulating portions of the motor cortex and
  noting the body responses
• Delgado illustrated this by making a monkey smile
  and forcing a patient to make a fist

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• 4. Sensory Functions
• a. The sensory cortex the area at the front of
  the parietal lobes that registers and processes
  body sensations
• b. The more sensitive the body region the
  greater the area dedicated to this body part.
• c. Examples include if you lose a finger the
  area dedicated for that finger will reorganize
  itself to pick up sensations from neighboring
  fingers

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Motor and Sensory Areas
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• 5. Association Functions
• a. Association areas areas of the cerebral
  cortex that are not involved in primary motor or
  sensory functions
• b. Rather they are involved in higher mental
  functions such as learning remembering, thinking
  and speaking
• c. Examples of association area damage
• Wilder Penfields sister had damage to her
  frontal lobe, and although she had perfect
  knowledge of cake recipes could not bake a cake.
• Phineas Gage was a railroad worker who suffered
  sever brain damage. As a result his limbic
  system (emotional center) was seperated from his
  frontal lobe (planning center) He was now
  irritable and quick to be angry

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• 6. Language
• a. Aphasia impairment of language usually
  caused by left hemisphere damage either to
  Brocas area (impairing speaking) or to
  Wernickes area (impairing understanding).
• b. Brocas area an area of the frontal lobe
  usually in the left hemisphere
• It directs the muscle movements involved in
  speech
• Discovered when Paul Broca treated his famous
  patient Tan
• c. Wernickes Area a brain area involved in
  language comprehension and expression usually
  found in the left temporal lobe

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• e. Geschwinds description of how we read aloud
• The visual cortex in the occipital lobe receives
  written words as visual stimulation
• The angular gyrus transforms the visual
  representations into an auditory code
• Wernickes area interprets the auditory code
• Brocas Area controls the muscled for speech via
  the motor cortex
• The motor cortex signals the appropriate muscles
  to make speech

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GHOTI
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• 7. Brain Reorganization
• a. Plasticity the brains capacity for
  modification as evident in brain reorganization
  following damage (specifically in children) and
  in experiments on the effects of experience on
  brain development
• b. Examples include a man who had ½ of his brain
  removed and yet made it through college and grad
  school.

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VII. Our Divided Brains

• A. Splitting the Brain
• 1. Sperry and Myers used classical conditioning
  to train a cat while one eye was closed. When
  tested with the opposite eye open the cat was
  unable to produce the newly learned behavior.
  The study showed that the cat must be conditioned
  for both eyes.
• 2. Vogel and Bogen were two neurosurgeons who
  proposed splitting the brain of one of their
  severely epileptic patients, a 48 year old war
  veteran referred to as W.J.

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Split Brain Experiment
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• 3. Upon awakening the patients seemed to be fine
  able to think and function normally.
• 4. Roger Sperry invented an apparatus to study
  the split brain patients. This apparatus
  involved flashing different words to each visual
  field while also allowing for the patient to
  blindly feel objects with both hands.
• 5. The subject is asked to fixate on the center
  of the screen while words are flashed very
  briefly onto the screen. The subjects were then
  asked to identify vocally and with their hands
  what they saw.

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• 6. When intact brain patients participate they
  have no trouble identifying the word key ring
• 7. Split brain patients on the other hand report
  only the word ring which was presented in their
  right field of vision which is processed by the
  left brain which is also the verbal side of the
  brain.
• 8. If asked to identify the object with their
  left hand (controlled by the right brain) they
  will search for the key that they would adamantly
  deny seeing.
• 9. One way they can compensate is by saying the
  word out loud so both sides become aware of it or
  by pointing to communicate between the right and
  left hemispheres
• 10. The results may have been over-generalized
  to the fields of education and literature.

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• B. Studying Hemispheric Difference in the Intact
  Brain
• 1. Perceptual task are centered in the right
  hemisphere
• a. For example most people recognize a picture
  more quickly when it is projected to the right
  brain
• b. Although the left brain is better at
  recognizing words the right brain is better at
  identifying abstract relationships between words
• c. Faces are recognized in the right brain

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• 2. Language tasks are generally centered in the
  left hemisphere
• a. For example most people recognize words more
  quickly when flashed to the left hemisphere
• C. Brain Organization and Handedness
• 1. Handedness and language
• a. About 95 of right handers process language
  in their left brain
• b. Left-handers are more diverse
• More than half process language in their left
  hemisphere
• About 25 process language in their right
  hemisphere
• And the other 25 process language in both
  hemispheres

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• 2. Is handedness inherited
• a. Right handedness goes back to prehistoric
  times
• b. Ultrasound shows that 9 out of 10 babies in
  the womb show a preference for sucking the right
  thumb
• c. Handedness is one of the few characteristics
  identical twins often do not share
• 3. The Case of the Disappearing Southpaws
• a. Studies show that left handers die earlier
  than right handers
• b. May be due to prenatal stresses and premature
  births

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• D. Hemispheric specialization
• 1. Left Brain specialization (analytic)
• a. Language
• Wernickes Area left temporal lobe normal
  speech without structure
• Brocas Area Left frontal lobe expressive
  area trouble putting speech into words
• b. Mathematical
• 2. Right Hemisphere specialization (creative)
• a. Spatial functions
• Pattern recognition such as faces
• Color discrimination (fine differences)
• b. Musical
• Variation in intonation
• Memory of musical patterns in right side

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VIII. Genetics and Environment

• A. Our Biological Blueprint
• 1. Chromosomes Thread like structures made of
  DNA molecules that contain the genes
• 2. DNA a complex molecule containing the
  genetic information that makes up the chromosomes
• 3. Genes The biochemical units of heredity
  that make up the chromosomes

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• 4. Genome The complete instructions for making
  an organism, consisting of all the genetic
  material in its chromosomes.

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• B. Evolutionary Psychology
• 1. The case of the tame fox
• a. Researchers in Russia selectively bred foxes
  to create a tame fox that was completely
  domesticated

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• b. Some 45,000 foxes and 40 years later, they
  have created a fox that can be a pet, replicating
  what may have happened between our ancestors and
  wolves that later became mans best friend.
• c. This shows that certain traits can be
  inherited and selected for survival

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• 2. Natural Selection
• a. The principle that among the range of
  inherited trait variations, those that lead to
  increased reproduction and survival will most
  likely be passed on to succeeding generations
• b. Mutation a random error in gene replication
  that leads to change in the sequence of
  nucleotides the source of all genetic diversity.

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• 3. Evolutionary Psychology the study of the
  evolution of behavior and the mind, using
  principles of natural selection.
• a. Natural selection has favored genes that
  designed both behavioral tendencies and
  information processing systems that solved
  adaptive problems faced by our ancestors.
• b. Thus contributing to the survival and spread
  of their genes.

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• 4. Evolution and sexuality
• a. Gender in psychology the characteristics
  whether biologically or socially influenced by
  which people define males and females.
• b. Sexuality especially attitudes towards sex is
  one of the greatest differences between the
  genders

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• c. Evolutionary psychologist would say that the
  fact that women nurtured the child, caused this
  difference
• Women mated wisely, while men mated widely.

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• Men are attracted to youthful women whose waist
  is three times as small as her hips suggesting
  child rearing.
• Women were attracted to healthy looking men, but
  especially those who seem mature, dominant bold
  and affluent.
• 5. Critique of the Evolutionary Perspective
• a. Starts with a behavior and works backwards so
  it could be tainted by hindsight bias
• b. Others say it will lead to a type of
  determinism and loss of free will.

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• C. Behavior Genetics
• 1. Behavior Genetics the study of the relative
  power and limits of genetic and environmental
  influences on behavior.
• 2. Environment every nongenetic influence from
  prenatal nutrition to the people and things
  around us.

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• 3. Twin Studies
• a. Identical twins twins who develop from a
  single fertilized egg that splits in two creating
  two genetically identical organisms

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• b. Fraternal twins twins who develop from
  separate eggs. They are genetically no closer
  than brothers and sisters, but the share fetal
  development

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• c. Twin and Adoption Studies
• Many cases of twins who have been separated at
  birth and raised independently have been study to
  reveal the relative importance of both genetics
  and environment.
• The findings although criticized by some show
  many startling similarities.
• With adoption studies we look at siblings who
  were separated at birth and raised independently.
  
• The findings point to the importance of genetics
  over environment.

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• 4. Heritability the proportion of variation
  among individuals that we can attribute to genes.
  The heritability of a trait may vary, depending
  on the range of populations and environments
  studied.

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• 5. Molecular Genetics the subfield of biology
  that studies the molecular structure and function
  of genes
• D. Genetics and Human Disorders
• 1. The X Chromosome in humans females most
  often have two x-chromosomes, while men only have
  one
• 2. The Y Chromosome in humans males have on
  Y-chromosome whereas women have none

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• 3. Genetic Disorders
• a. Down Syndrome usually with 3 copies of
  chromosome 21 in their cells, individuals are
  typically mentally retarded, have a round head,
  flat nasal bridge, protruding tongue, small round
  ears, a fold in the eyelid and poor muscle tone
  and coordination

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• b. Albinism a recessive trait that produces
  lack of pigment and involves quivering eyes and
  inability to perceive depth with both eyes
• c. Hunningtons Disease a dominant gene defect
  that involves degeneration of the nervous system
  characterized by tremors, jerky motions,
  blindness and death
• d. Klinefelters syndrome males with XXY
  chromosomes often results in taller, leaner men
  with less bone density and muscle strength

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• e. PKU phenylketonuria is a recessive trait
  that results in severe, irreversible brain damage
  unless the baby is fed a special diet low in
  phenylalanine
• f. Tay-Sachs syndrome Recessive trait that
  produces progressive loss of nervous function and
  death in a baby.
• g. Turners Syndrome females with only one X
  chromosome. They are usually short, often
  sterile and have difficulty with calculations.

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IX. Environmental Influence and Genetics

• A. Culture
• 1. Culture is the enduring behaviors, ideas,
  attitudes and traditions shared by a large group
  of people and transmitted from one generation to
  the next.
• 2. Norm a norm is an understood rule for
  accepted and expected behavior. Norms prescribe
  proper behavior

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• 3. Personal Space the buffer zone we like to
  maintain around our bodies
• 4. Memes Self replicating ideas, fashion and
  innovations passed from person to person.
• B. The Nature and Nurture of Gender
• 1. Role A set of expectations about a social
  position.

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• 2. Gender Role a set of expected behaviors for
  males and females.
• 3. Gender Identity ones sense of being either
  male or female
• 4. Gender Typing the acquisition of
  traditional masculine or feminine roles

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• 5. Social Learning Theory the theory that we
  learn social behavior by observing and imitating
  and being rewarded or punished.
• 6. Gender Schema Theory the theory that
  children learn from their cultures a concept of
  what it means to be a male and female and that
  they adjust their behavior accordingly.

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Prompt 7

• Draw a brain and label the structures of the
  cerebral cortex.

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Essay Question 1

• Describe the structure and function of the
  various parts of a neuron. Explain the process
  involved when a neuron goes from a state of rest
  to communicating with another neuron.

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Bell-ringer 10

• Get a text book out of the closet and then label
  the two brain worksheets.

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