Summary Myers Psychology Book - Chapter 2 Notes

Myers Ch 2

The Mind
 Phrenology
o Plato located the brain in the head
o Aristotle believed mind was in the heart
o Gall said that studying bumps on the skull reveals mental abilities
o Localization of brain function
 Neurons
o Nerve cells “talk” using electricity and chemical messages
o Biopsychosocial systems
o Structure and function
 Cell body
 Basic part of a neuron (and branching fibers)
 Dendrite
 “Listen”
 Bushy fibers
 Branching extensions of neurons
 Receive messages
 Conduct impulses
 Axon
 “Speak”
 Lengthy fibers
 Neuron extension
 Passes messages to other neurons or to muscles/glands
 Encased by myelin sheath
 Synapse
 Junction between axon tip of sending neuron and dendrite of
receiving neuron
 Myelin
 Fatty tissue that insulates axons
 Multiple sclerosis results from degeneration
 Insulated by glial cells
o More in a more complex brain
o Communication between neurons
 Synaptic gap
 Between dendrites and axons
 Gap between receiver and sender
 Action potentials
 Impulse fired by neuron
o Refractory period is inactivity after a neuron has fired
o Stronger stimuli cause more neurons to fire
 Travels down an axon

, o Depolarization
 All or none response
o Neuron’s reaction of either firing or not firing
 If fires, it is a full strength response
 Neurotransmitters
o Cross synaptic gaps between neurons
o Glutamate
 Excitatory
 Memory
 Too much = migraines or seizures
o GABA
 Inhibitory
 Too little = seizures or insomnia
o Serotonin
 Mood, hunger, sleep, arousal
 Too little = depression
o Dopamine
 Movement, learning, attention, emotion
 Too much = schizophrenia
 Too little = Parkinson’s
 Reuptake of neurotransmitters
o Reabsorption of a neurotransmitter by the sender (axon)
 Effect of drugs
o Endorphins are like opiates
o Agonist
 Increases a neurotransmitter’s action
 May increase production or release
 May block reuptake by mimicking
o Antagonist
 Blocks a neurotransmitter’s action
 May block production or release
 Nervous System
o Adrenal glands arouse the body
o Central Nervous System
 Brain and spinal cord
 Sensory/afferent neurons
 Carry messages to CNS
 Motor/efferent neurons
 Carry messages from CNS
o Brain Regions
 Brainstem
 Innermost region
 Where spinal cord swells at the skull (medulla)