Psychology Lecture One & Two
Thinking Critically with Psychological Science
Common sense is not sufficient to understand and predict behavior...scientific
method is necessary
Intuitive/Folk Psychology: Intuition may not always be correct. Many
psychological findings have been counterintuitive.
Facial attractiveness: Intuition says distinctive faces are attractive. Science
says that average faces are attractive. Intuition says that an individual's
judgement is consistent over time. Science says that interpretation of the
attractiveness of a face is inconsistent and depends on hormonal state for
example. When a woman is ovulating, the male with the most testosterone
driven features (strong jaw for example) is most attractive.
Notes on Modules 4
Neural and Hormonal Systems
-Building blocks are neurons
-Every neuron has a cell body and branching fibers. Dendrite fibers receive
information and conduct it into the cell body while the axon fiber carries it to the
axon terminal to conduct impulses
-Some axons are encased in myelin sheath which conduct impulses quicker. The
degeneration of the myelin sheath is what leads to multiple sclerosis
-When an impulse reaches the threshold potential, an impulse will fire and the axon
brings in sodium ions to depolarize which causes all the channels along the line to
follow in a dominos effect.
-During a refractory period, the neuron will open potassium channels to allow
positive ions to flood out to return to its resting potential of -70 mv.
-Increasing stimulation does not affect the neural impulse intensity. Strong
stimulus simply triggers MORE neurons to fire.
-Axon terminal of one neuron is separated from the dendrite of the next neuron by
a synaptic cleft across which neurotransmitters carry messages to bind to
receptors on the receiving neuron.
-Particular brain pathways can only use certain neurotransmitters and different
neurotransmitters affect different behaviours.
ACh is a neurotransmitter which plays a role in learning and memory. If Ach
transmission is blocked, paralysis could occur as muscle contraction cannot happen
-If the brain is flooded with artificial opiates to intensify a good feeling, it will
stop making it naturally causing the body to need to depend on the drug. -Drugs and other chemicals affect brain chemistry at synapses by exciting or
inhibiting the neuron firing.
-Agonist molecules are similar enough to some neurotransmitters that they can
bind to a receptor and mimic effects. Agonists are present in many opiates
-Antagonists can also bind to receptors, but they block neurotransmitters and do
not have the same effects and cannot stimulate the receptor. Antagonists are
present in many poisons.
-Brain and spinal cord make up the central nervous system
-Peripheral nervous system is made up of sensory neurons which carry messages
from tissues and receptors to interneurons in the brain or spinal cord, which send
out motor neurons to muscles to respond.
-Peripheral nervous system has somatic and autonomic components, with somatic
being voluntary and autonomic being automatic.
Autonomic nervous systems can have parasympathetic impulses, which lower heart
rate or blood sugar, while sympathetic impulses raise blood sugar or heart rate.
These two systems work together to keep homeostasis within the body.
-On spinal cord, ascending neural fibers send up sensory information while
descending fibers send back motor information.
-Reflexes are automatic responses to stimuli and result from a sensory neuron and
motor neuron communicating in the spinal cord without the interneuron input.
-Connected with the nervous system is the endocrine system, which use the
chemical messengers of hormones. Some hormones are chemically similar to
neurotransmitters. Endocrine messages are much slower then neural messages, but
with longer lasting effects.
-In danger, the adrenal gla