Introduction to Psychology: Lecture Notes

Introduction to Psychology
Lecture 2
Vrije Universiteit Amsterdam
Period 1, Week 1

Communication among neurons
 Either fire or do not fire
 All-or-none law
 Intensity variations by
1. No of neurons firing
2. Variations in firing rate
 Neurons interact
 Via synapses
 Through chemical substances

 Synapse
 The place where a signal passes from one nerve cell to another

 Neurotransmitters
 Chemical substances that transmit signals from one neuron to another
 Lock-and-key model
 Effect is terminated by
1. Autoreceptors
2. Synaptic reuptake
3. Enzymes

 The binding of a neurotransmitter with a receptor produces an excitatory or
inhibitory signal




 Drugs
 Agonists
 Increase of precursor
 Counteracting the cleanup enzymes
 Blocking the reuptake
o SSRIs
 Mimicking the transmitter’s action
o Because it fits into the receptor

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,  Antagonists – antipsychotics
 Decrease precursor (or neurotransmitter)
 Increase effectiveness cleanup enzymes
 Enhance the reuptake
 Blocking of receptors

Studying the brain
 19th century > Phrenology
 Bumps on the skull were interpreted in terms of personality traits
 Methods for studying the brain
 Clinical observation of patients with brain damage
 Experimental techniques
 Invasive: animal studies
 TMS (Transcranial Magnetic Stimulation)
 EEG
 ERP
 fMRI
 MRI
 PET



Introduction to Psychology
Lecture 3
Vrije Universiteit Amsterdam
Period 1, Week 2

Consciousness: one’s subjective experience of the world, resulting from brain
activity
 Brain and mind are inseparable
 Everyone experiences consciousness personally
 Arises as a function of which brain circuits are active
 Global Workspace Model
 Sometimes unconscious processes lead people to do things that their
conscious minds struggle to explain
 After-the-face explanations

Variations in consciousness
 Attention: refers to the process that enables you to focus selectively on some
things and avoid focusing on others
 There is a limit to the number of things you can be conscious of at the
same time
 Unattended behavior may still affect behavior > subliminal perception
 Yet, without much awareness > change blindness
 Cocktail party phenomenon
 Sometimes the unattended information breaks through
 Sleep
 Why do we sleep? > theories about sleep
 Restorative theory
 Circadian rhythm theory

2

,  Facilitation of learning theory > strengthening of neural
connections and memory consolidation
 Dreams: products of an altered state of consciousness in which images
and fantasies are confused with reality
 Non-REM dreams: dull
 REM dreams: bizarre and intense
 Drugs
 Addiction: drug use that remains compulsive despite its negative
consequences
 Physical and psychological dependence
 Tolerance: increasing amounts of a drug needed to achieve the
intended effect
 Withdrawal: physiological and psychological state characterized
by feelings of anxiety, tension and cravings for the addictive
substance

Four major categories of drugs
 Stimulants: drugs that increase behavioral and mental activity and activate
the sympathetic nervous system (e.g. amphetamines, methamphetamines,
cocaine, nicotine, caffeine)
 Depressants: reduce behavioral and mental activity by depressing the central
nervous system (e.g. alcohol, benzo’s, barbiturates)
 Opiates (narcotics): depress or slow down the central nervous system, relieve
pain and suffering (e.g. heroin, morphine, codeine)
 Hallucinogens (psychedelics): produce alterations in cognition, mood and
perception (e.g. LSD, Mescaline – from Peyote cactus, psilocybin mushrooms)
 Many do not fit into these four categories (XTC, MDMA, marijuana)



Introduction to Psychology
Lecture 4
Vrije Universiteit Amsterdam
Period 1, Week 2

Sensation: the detection of external stimuli and the transmission of this information
to the brain
Perception: the processing, organization, and interpretation of sensory signals

Distal stimulus > proximal stimulus > transduction > sensation > perception

The senses
 Vision
 Hearing
 Taste
 Smell
 Skin senses
 Vestibular sense – sense of balance
 Kinesthesis – sense of muscles/tendants/joints



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