Unit 1: Scientific Foundations of Psychology
11/19/25 16:31
Psychology: the science of behavior and mental processes.
Integrated/Biopsychological approach incorporates biological, psychological, and social-cultural
viewpoints. For example, biology = melatonin release, psychological = habits, social-cultural = school.
The scientific attitude prepares us to think harder and smarter, which is called critical thinking. It
consists of curiosity, skepticism, humility.
Seven perspectives in psychology:
1. Behavioral: observable behavior and how it is learned through environmental interaction,
primarily through conditioning (classical/operant).
2. Cognitive: mental processes that are behind the behavior, such as perception, learning, and
thinking.
3. Humanistic: personal growth, focused on individual's choice, experience, and fulfillment.
4. Psychodynamic: how behavior springs from unconscious. Emphasizes hidden desires and fears,
mostly as a result of childhood.
5. Biological: physical and biological processes, such as the nervous system, hormones, and genetics.
6. Evolutionary: how human's mind shaped due to natural selection and evolution.
7. Sociocultural: how social and cultural environment influence humans' behaviors, beliefs, and
development.
Psychology subfields:
Basic research is pure science as it increases the scientific knowledge base.
Basic research subfields:
1. Developmental psychology: the study of our changing abilities as we develop.
2. Educational psychology: the study of influences on cognitive processes, such as learning and
teaching.
3. Psychometric/quantitative psychology: study of measurements of our abilities, attitudes, and
trades.
Applied research aims to solve practical problems.
Applied research subfields:
1. Forensic psychology: applied psychological principles to legal issues.
2. Health psychology: psychology's contribution to promoting health and prevent diseases.
3. Industrial-organizational (I/0) psychology: relationship between people and their working
environment.
4. Neuropsychology: relationship between neurological processes (the nervous system) and
behavior.
5. Rehabilitation psychology: works with people who have lost optimal functioning after an accident,
illness, etc.
6. School psychology: intervention for children in educational settings.
7. Sport psychology: factors that influence or are influenced by sports.
8. Clinical psychology: treats people with psychological disorders.
9. Counseling psychology: helps people adjust to life transitions or make lifestyle changes.
10. Psychiatrist: works with people with disorders, but can actually provide medical treatment.
Psychiatrists go to medical schools.
Critical thinking blocks:
1. Hindsight bias: the tendency to believe, after learning an outcome, that one would have foreseen
it. AKA "I knew it all long" phenomenon.
2. Overconfidence: humans tend to think we know more than we do. Underestimating risks, ignoring
feedback.
3. Gambler's fallacy: perceiving order in random events. If you roll the dice and get 6 multiple times,
you start thinking 6 is overdue and it’s less likely to get 6 again, even though each roll is a 1/6
chance.
4. Confirmation bias: the tendency to gather evidence that confirms preexisting expectations.
Dismissing or failing to see what does not support your idea or belief.
5. Belief perseverance: the tendency to cling to one's belief even after the factual evidence that
they're wrong.
Research methods (non-experimental):
1. Case study: one individual or a specific group of people is studied in depth. It is not generalizable,
but provides very detailed info.
2. Naturalistic observation: observing and recording behavior in natural, everyday setting without
interference. It provides true picture, but does not provide any control.
3. Meta-analysis: combining results of different studies. It is great for a big picture summary, but
hides real differences.
4. Correlation: two factors may vary together, and thus how well either factor predicts the other.
One DOES NOT causes the other, but it shows the relationship between two variables.
Correlation coefficient: a statistical index of the relationship between two things.
From –1 to +1, and the closer to zero, the weaker the relationship.
Experimental study: a research method in which an investigator manipulates one or more factors. It
reveals the cause and effect on some behaviors.
• Random assignment: randomly placing participants into different groups, such as control and
experimental. Done to ensure that preexisting differences do not affect the study.
• Experimental group: group being manipulated or trying treatment.
• Control group: group that is not being manipulated.
• Independent variable: something in the experiment that is changed.
• Dependent variable: something in the experiment that changes because of an independent
variable.
• Confounding variable: a factor other than the factor being studied that can influence a study's
result.
• Operational definition: a clear, specific, and measurable definition of a concept or variable being
studied. Done to allow replication.
• Generalizability: the extent to which a study can be applied to a broader population other than
the group being studied.
• Sample: a group of individuals selected from a larger population for the experiment.
• Population: all people being studied.
For example, a population is college students everywhere, and the 100 college students you survey on
your campus are the sample.
Different studies:
1. Cross-sectional study: proved information about different groups at one point in time.
Example: comparing the reading ability of 6, 8, and 10 year olds at the same time.
2. Longitudinal study: observing the same group of people over time.
3. Cohort study: a type of longitudinal study where a group shares a common factor. For example,
birth year or a shared experience/event.
All cohort studies are longitudinal, but not all longitudinal studies are cohort, because not all of them
have to share a common factor.
Surveys:
Wording effect: even subtle changes in question will affect our mind. Can result in misleading or biased
survey results.
Experiment ethics:
1. Informed consent: providing participants with the detail of a study, so that they can give consent.
2. Informed assent: parental consent if minor is involved.
3. An Institutional Review Board (IRB): read through research proposals to safeguard participants
and may or may not grand approval.
4. Confidentiality: keeping information about participants in secret.
5. Protect from harm: protecting participants from potential harm to their mental or physical health.
6. Debrief: explain the research afterward. Say if you lied at the beginning with a purpose of
successful experiment.
Measures of central tendency/variation:
1. Mean: the average, measured by adding all scores and then dividing by the number of scores.
2. Median: the middle score in dataset (must be from least to greatest to determine.
3. Mode: the most frequent occurring score.
4. Range: the difference between the highest and lowest scores.
5. Standard deviation: a computed measure of how much scores may vary around the mean. Reveals
consistency. Smaller number = greater consistency.
In normal curve: 68% score within one standard deviation, 95% score withing two standard deviations.
Statistics:
Statistical significance: if the results are valid or just because of mistake/chance/coincidence.
You want a p value under 5 percent.
Percentile rank: shows the percentage of scores in a distribution that are equal to or lower than a
specific score.
Normal distribution: always symmetrical curve.
Negatively skewed: closer to the right.
Positively skewed: closer to the left.
Bimodal distribution curve: two modes that create two peaks.
, Unit 2: Biological bases of behavior
11/20/25 22:56
Neurons:
1. Sensory (afferent) neurons: neurons that carry incoming information from the body's tissues and
sensory receptors to the brain and spinal cord.
2. Motor (efferent) neurons: neurons that carry outgoing information from the brain and spinal cord;
they communicate to the muscles and glands.
3. Interneurons: neurons within the brain and spinal cord; they communicate internally and process
information between the sensory inputs and motor output.
Parts of neurons:
1. Dendrites: branching extensions at the cell body. They receive messages from other neurons.
2. Cell body (soma): life support center of the nucleus (processing).
3. Axon: Long single extension of a neuron, covered with myelin.
4. Myelin: protective covering to insulate and speed up messages through neurons.
At rest, the neuron has a positively charged outside and negatively inside, maintained by selective
permeability and the sodium potassium pump. Incoming signals through dendrites can be excitatory
(encouraging fire) or inhibitory (discouraging fire). if excitatory signals exceed inhibitory signals enough
to reach threshold, the neuron fires an action potential in all-or-none response. During depolarization
sodium ions rush in through open channels briefly reversing the charge inside the axon. This triggers a
chain reaction (like falling dominos) that sends the electrical impulse down the axon. When the action
potential reaches the axon terminals (branched endings of an axon that transmit messages to other
neurons, muscles, or glands), neurotransmitters (chemicals) are released into the synapse (space
between two neurons). These chemical messengers bind to receptor sites on the next neuron.
Afterwards, excess neurotransmitters are removed by reuptake (reabsorption), broken down by
enzymes, or drifting away.
Neurotransmitters:
• Substance P: alerts the brain the body is in pain.
• Serotonin: affects mood, regulates appetite, sleep.
• Norepinephrine: increased alertness needed for fight/flight and focus.
• Acetylcholine: enables muscle action, learning memory.
• GABA: helps regulate anxiety, stress, and cognitive abilities.
• Glutamate: crucial in cognitive processes.
• Endorphins: influences the perception of pain.
• Dopamine: brain's reward system and experiencing pleasure.
Agonist: stimulating response (mimic), such as morphine or heroin.
Antagonist: blocking response, such as Botox.
Nervous system:
1. Central nervous system: the brain and spinal cord.
2. Peripheral nervous system: the sensory and motor neurons that connect the central nervous
system to the rest of the body.
Autonomic nervous system: controls the glands and other muscles, such as digestion and heartbeat.
○ Sympathetic nervous system: activates the body, digestion stops.
○ Parasympathetic nervous system: calms the body (rest and digest).
Somatic nervous system: controls the body's skeletal muscles, such as raising your hand.
Endocrine system: the body's slow chemical communication system; a set of glands that secrete
hormones into the bloodstream.
• Hormones: chemical messengers that are manufactured by the endocrine glands, travel through
the bloodstream, and affect other tissues. Melatonin for sleep, insulin for blood sugar control,
adrenalin.
• Pituitary gland: the endocrine system's most influential. Under the influence of hypothalamus, it
regulates growth and controls other endocrine glands.
Neuroimaging:
1. EEG: measures the electrical activity of the brain by using small electrodes placed on the scalp.
2. MRI: uses radio waves to create detailed image. Donut :)
3. fMRI: maps brain activity by measuring changes in the blood flow.
Brain structures:
• Forebrain: cerebrum, cerebral cortex (4 lobes), thalamus, hypothalamus, pituitary gland, limbic
system, nucleus accumbens.
• Midbrain: located between the forebrain and hindbrain; helps with hearing and vision.
• Hindbrain: brainstem, cerebellum, medulla, reticular formation.
• Brainstem: the oldest part of the brain, beginning where the spinal cords wheels and enters the
skulls. It is responsible for automatic survival functions.
Medulla: breathing.
Reticular formation: the band of nerves that travels up brainstem for alertness/arousal.
• Cerebellum: balance/coordination.
• The limbic system: a doughnut-shaped system of neural structures at the border of the brainstem
and cortex that is associated with emotions, such as fear, aggression, drive for food and sex.
Hippocampus: new memories.
Amygdala: fear/aggression.
Hypothalamus: controls endocrine system, reward center, hunger/thirst, temperature.
• The cerebral cortex: the intricate fabric of interconnected neural cells covering the cerebral
hemispheres; the body's ultimate control and information processing center.
Left hemisphere: verbal, math, analytics.
Right hemisphere: nonverbal, spatial, holistic.
Corpus callosum: band of fibers that connects the two hemispheres, allowing messages to pass back and
forth.
Parietal lobe: at the top of the head; receive sensory input for touch and body position.
Occipital lobe: at the back of the head; includes areas that receive info from the visual fields.
Temporal lobe: roughly above the ears; includes the auditory areas, each receiving info primarily from
the opposite ear.
Frontal lobe: just behind the forehead; involved in speaking and muscle movements, also in making
plans and judgement.
Motor cortex: an area at the rear of the frontal lobe that controls voluntary movements.
Broca's area: responsible for speech production and language comprehension.
Wernicke's area: located in the left temporal lobe; critical for language comprehension.
Plasticity: the brain's ability to change, especially during childhood, by reorganizing after damage or by
building new pathways based on experience.
Neurogenesis: the formation of new neurons.
When the corpus callosum is absent (surgery, might be because of epilepsy), objects presented in the
right field can be names, while objects in the left visual field can't.
Differences
• Behavior genetics: study of humans' differences and the weight of relative effect of heredity and
environment.
• Epigenetics: the study of how genes can be turned off and on.
• Dizygotic twins: different DNA, same environment. If intelligence is the same, it must be due to
the environment. If different, due to genetics.
• Monozygotic twins: same DNA, different environment. If intelligence is the same, It must be due
to genetics. If different, due to the environment.
Sleep pattern and theories:
• Right amount of sleep helps sustain better mood and perform more efficiently and accurately.
Sleep feeds creative thinking and helps us recreate memories.
• Consciousness: our level of awareness and our environment.
• Circadian rhythm: occurs on a 24-hour cycle and include sleep and wakefulness. Can be altered by
artificial light.
Sleep stages:
1. NREM 1: transition period between wakefulness and sleep; lasts about 5-10 minutes.
2. NREM 2: body temperature drops and heart rate begins to slow, brain begins to produce sleep
spindles; lasts 20 minutes.
3. NREM 3: muscles relax, blood pressure and breathing rate drops; deepest sleep.
4. REM: brain becomes more active, body becomes relax, dreams occur, eyes move rapidly.
Sleep disorders:
• Insomnia: ongoing difficulty falling or staying asleep.
• Narcolepsy: sudden attacks of overwhelming sleepiness.
• Sleep apnea: stops breathing repeatedly while sleeping.
• Sleepwalking/talking: talking or walking during NREM 3.
• Night terrors: sudden episodes of fear and aggression during sleep, screaming, but still sleeping
and not remembering this in the morning; occurs in non-REM sleep.
While nightmares are scary dreams that occur in REM sleep.
• REM sleep behavior disorder: acting out dreams during REM.
• Shift work: difficulty or feeling tired during work shifts.
• Jetlag: internal body clock change after traveling.
• Restless leg syndrome: prevents from falling asleep due to leg tremors.
Dreams:
Dreams have no meaning. When we sleep, our brain produces random dream images (activation) which
are combined by the brain into a story (synthesis).
Drugs:
1. Depressants: slow the body down.
Example: Alcohol, heroin, morphine, codeine.
2. Stimulants: pump the body up.
Example: caffeine, nicotine, cocaine.
3. Hallucinogens: mind-manifesting drugs that may distort perception.
Example: LSD, marijuana.
• Tolerance: repeated exposure to a drug makes the drug's effect lessen. It takes greater quantities
to get the desired effect.
• Dependence: absence of a drug may lead to a feeling of physical pain, intense cravings, and
negative emotions.
• Withdrawal: upon stopping the use of drug, users experience the undesirable effects.
11/19/25 16:31
Psychology: the science of behavior and mental processes.
Integrated/Biopsychological approach incorporates biological, psychological, and social-cultural
viewpoints. For example, biology = melatonin release, psychological = habits, social-cultural = school.
The scientific attitude prepares us to think harder and smarter, which is called critical thinking. It
consists of curiosity, skepticism, humility.
Seven perspectives in psychology:
1. Behavioral: observable behavior and how it is learned through environmental interaction,
primarily through conditioning (classical/operant).
2. Cognitive: mental processes that are behind the behavior, such as perception, learning, and
thinking.
3. Humanistic: personal growth, focused on individual's choice, experience, and fulfillment.
4. Psychodynamic: how behavior springs from unconscious. Emphasizes hidden desires and fears,
mostly as a result of childhood.
5. Biological: physical and biological processes, such as the nervous system, hormones, and genetics.
6. Evolutionary: how human's mind shaped due to natural selection and evolution.
7. Sociocultural: how social and cultural environment influence humans' behaviors, beliefs, and
development.
Psychology subfields:
Basic research is pure science as it increases the scientific knowledge base.
Basic research subfields:
1. Developmental psychology: the study of our changing abilities as we develop.
2. Educational psychology: the study of influences on cognitive processes, such as learning and
teaching.
3. Psychometric/quantitative psychology: study of measurements of our abilities, attitudes, and
trades.
Applied research aims to solve practical problems.
Applied research subfields:
1. Forensic psychology: applied psychological principles to legal issues.
2. Health psychology: psychology's contribution to promoting health and prevent diseases.
3. Industrial-organizational (I/0) psychology: relationship between people and their working
environment.
4. Neuropsychology: relationship between neurological processes (the nervous system) and
behavior.
5. Rehabilitation psychology: works with people who have lost optimal functioning after an accident,
illness, etc.
6. School psychology: intervention for children in educational settings.
7. Sport psychology: factors that influence or are influenced by sports.
8. Clinical psychology: treats people with psychological disorders.
9. Counseling psychology: helps people adjust to life transitions or make lifestyle changes.
10. Psychiatrist: works with people with disorders, but can actually provide medical treatment.
Psychiatrists go to medical schools.
Critical thinking blocks:
1. Hindsight bias: the tendency to believe, after learning an outcome, that one would have foreseen
it. AKA "I knew it all long" phenomenon.
2. Overconfidence: humans tend to think we know more than we do. Underestimating risks, ignoring
feedback.
3. Gambler's fallacy: perceiving order in random events. If you roll the dice and get 6 multiple times,
you start thinking 6 is overdue and it’s less likely to get 6 again, even though each roll is a 1/6
chance.
4. Confirmation bias: the tendency to gather evidence that confirms preexisting expectations.
Dismissing or failing to see what does not support your idea or belief.
5. Belief perseverance: the tendency to cling to one's belief even after the factual evidence that
they're wrong.
Research methods (non-experimental):
1. Case study: one individual or a specific group of people is studied in depth. It is not generalizable,
but provides very detailed info.
2. Naturalistic observation: observing and recording behavior in natural, everyday setting without
interference. It provides true picture, but does not provide any control.
3. Meta-analysis: combining results of different studies. It is great for a big picture summary, but
hides real differences.
4. Correlation: two factors may vary together, and thus how well either factor predicts the other.
One DOES NOT causes the other, but it shows the relationship between two variables.
Correlation coefficient: a statistical index of the relationship between two things.
From –1 to +1, and the closer to zero, the weaker the relationship.
Experimental study: a research method in which an investigator manipulates one or more factors. It
reveals the cause and effect on some behaviors.
• Random assignment: randomly placing participants into different groups, such as control and
experimental. Done to ensure that preexisting differences do not affect the study.
• Experimental group: group being manipulated or trying treatment.
• Control group: group that is not being manipulated.
• Independent variable: something in the experiment that is changed.
• Dependent variable: something in the experiment that changes because of an independent
variable.
• Confounding variable: a factor other than the factor being studied that can influence a study's
result.
• Operational definition: a clear, specific, and measurable definition of a concept or variable being
studied. Done to allow replication.
• Generalizability: the extent to which a study can be applied to a broader population other than
the group being studied.
• Sample: a group of individuals selected from a larger population for the experiment.
• Population: all people being studied.
For example, a population is college students everywhere, and the 100 college students you survey on
your campus are the sample.
Different studies:
1. Cross-sectional study: proved information about different groups at one point in time.
Example: comparing the reading ability of 6, 8, and 10 year olds at the same time.
2. Longitudinal study: observing the same group of people over time.
3. Cohort study: a type of longitudinal study where a group shares a common factor. For example,
birth year or a shared experience/event.
All cohort studies are longitudinal, but not all longitudinal studies are cohort, because not all of them
have to share a common factor.
Surveys:
Wording effect: even subtle changes in question will affect our mind. Can result in misleading or biased
survey results.
Experiment ethics:
1. Informed consent: providing participants with the detail of a study, so that they can give consent.
2. Informed assent: parental consent if minor is involved.
3. An Institutional Review Board (IRB): read through research proposals to safeguard participants
and may or may not grand approval.
4. Confidentiality: keeping information about participants in secret.
5. Protect from harm: protecting participants from potential harm to their mental or physical health.
6. Debrief: explain the research afterward. Say if you lied at the beginning with a purpose of
successful experiment.
Measures of central tendency/variation:
1. Mean: the average, measured by adding all scores and then dividing by the number of scores.
2. Median: the middle score in dataset (must be from least to greatest to determine.
3. Mode: the most frequent occurring score.
4. Range: the difference between the highest and lowest scores.
5. Standard deviation: a computed measure of how much scores may vary around the mean. Reveals
consistency. Smaller number = greater consistency.
In normal curve: 68% score within one standard deviation, 95% score withing two standard deviations.
Statistics:
Statistical significance: if the results are valid or just because of mistake/chance/coincidence.
You want a p value under 5 percent.
Percentile rank: shows the percentage of scores in a distribution that are equal to or lower than a
specific score.
Normal distribution: always symmetrical curve.
Negatively skewed: closer to the right.
Positively skewed: closer to the left.
Bimodal distribution curve: two modes that create two peaks.
, Unit 2: Biological bases of behavior
11/20/25 22:56
Neurons:
1. Sensory (afferent) neurons: neurons that carry incoming information from the body's tissues and
sensory receptors to the brain and spinal cord.
2. Motor (efferent) neurons: neurons that carry outgoing information from the brain and spinal cord;
they communicate to the muscles and glands.
3. Interneurons: neurons within the brain and spinal cord; they communicate internally and process
information between the sensory inputs and motor output.
Parts of neurons:
1. Dendrites: branching extensions at the cell body. They receive messages from other neurons.
2. Cell body (soma): life support center of the nucleus (processing).
3. Axon: Long single extension of a neuron, covered with myelin.
4. Myelin: protective covering to insulate and speed up messages through neurons.
At rest, the neuron has a positively charged outside and negatively inside, maintained by selective
permeability and the sodium potassium pump. Incoming signals through dendrites can be excitatory
(encouraging fire) or inhibitory (discouraging fire). if excitatory signals exceed inhibitory signals enough
to reach threshold, the neuron fires an action potential in all-or-none response. During depolarization
sodium ions rush in through open channels briefly reversing the charge inside the axon. This triggers a
chain reaction (like falling dominos) that sends the electrical impulse down the axon. When the action
potential reaches the axon terminals (branched endings of an axon that transmit messages to other
neurons, muscles, or glands), neurotransmitters (chemicals) are released into the synapse (space
between two neurons). These chemical messengers bind to receptor sites on the next neuron.
Afterwards, excess neurotransmitters are removed by reuptake (reabsorption), broken down by
enzymes, or drifting away.
Neurotransmitters:
• Substance P: alerts the brain the body is in pain.
• Serotonin: affects mood, regulates appetite, sleep.
• Norepinephrine: increased alertness needed for fight/flight and focus.
• Acetylcholine: enables muscle action, learning memory.
• GABA: helps regulate anxiety, stress, and cognitive abilities.
• Glutamate: crucial in cognitive processes.
• Endorphins: influences the perception of pain.
• Dopamine: brain's reward system and experiencing pleasure.
Agonist: stimulating response (mimic), such as morphine or heroin.
Antagonist: blocking response, such as Botox.
Nervous system:
1. Central nervous system: the brain and spinal cord.
2. Peripheral nervous system: the sensory and motor neurons that connect the central nervous
system to the rest of the body.
Autonomic nervous system: controls the glands and other muscles, such as digestion and heartbeat.
○ Sympathetic nervous system: activates the body, digestion stops.
○ Parasympathetic nervous system: calms the body (rest and digest).
Somatic nervous system: controls the body's skeletal muscles, such as raising your hand.
Endocrine system: the body's slow chemical communication system; a set of glands that secrete
hormones into the bloodstream.
• Hormones: chemical messengers that are manufactured by the endocrine glands, travel through
the bloodstream, and affect other tissues. Melatonin for sleep, insulin for blood sugar control,
adrenalin.
• Pituitary gland: the endocrine system's most influential. Under the influence of hypothalamus, it
regulates growth and controls other endocrine glands.
Neuroimaging:
1. EEG: measures the electrical activity of the brain by using small electrodes placed on the scalp.
2. MRI: uses radio waves to create detailed image. Donut :)
3. fMRI: maps brain activity by measuring changes in the blood flow.
Brain structures:
• Forebrain: cerebrum, cerebral cortex (4 lobes), thalamus, hypothalamus, pituitary gland, limbic
system, nucleus accumbens.
• Midbrain: located between the forebrain and hindbrain; helps with hearing and vision.
• Hindbrain: brainstem, cerebellum, medulla, reticular formation.
• Brainstem: the oldest part of the brain, beginning where the spinal cords wheels and enters the
skulls. It is responsible for automatic survival functions.
Medulla: breathing.
Reticular formation: the band of nerves that travels up brainstem for alertness/arousal.
• Cerebellum: balance/coordination.
• The limbic system: a doughnut-shaped system of neural structures at the border of the brainstem
and cortex that is associated with emotions, such as fear, aggression, drive for food and sex.
Hippocampus: new memories.
Amygdala: fear/aggression.
Hypothalamus: controls endocrine system, reward center, hunger/thirst, temperature.
• The cerebral cortex: the intricate fabric of interconnected neural cells covering the cerebral
hemispheres; the body's ultimate control and information processing center.
Left hemisphere: verbal, math, analytics.
Right hemisphere: nonverbal, spatial, holistic.
Corpus callosum: band of fibers that connects the two hemispheres, allowing messages to pass back and
forth.
Parietal lobe: at the top of the head; receive sensory input for touch and body position.
Occipital lobe: at the back of the head; includes areas that receive info from the visual fields.
Temporal lobe: roughly above the ears; includes the auditory areas, each receiving info primarily from
the opposite ear.
Frontal lobe: just behind the forehead; involved in speaking and muscle movements, also in making
plans and judgement.
Motor cortex: an area at the rear of the frontal lobe that controls voluntary movements.
Broca's area: responsible for speech production and language comprehension.
Wernicke's area: located in the left temporal lobe; critical for language comprehension.
Plasticity: the brain's ability to change, especially during childhood, by reorganizing after damage or by
building new pathways based on experience.
Neurogenesis: the formation of new neurons.
When the corpus callosum is absent (surgery, might be because of epilepsy), objects presented in the
right field can be names, while objects in the left visual field can't.
Differences
• Behavior genetics: study of humans' differences and the weight of relative effect of heredity and
environment.
• Epigenetics: the study of how genes can be turned off and on.
• Dizygotic twins: different DNA, same environment. If intelligence is the same, it must be due to
the environment. If different, due to genetics.
• Monozygotic twins: same DNA, different environment. If intelligence is the same, It must be due
to genetics. If different, due to the environment.
Sleep pattern and theories:
• Right amount of sleep helps sustain better mood and perform more efficiently and accurately.
Sleep feeds creative thinking and helps us recreate memories.
• Consciousness: our level of awareness and our environment.
• Circadian rhythm: occurs on a 24-hour cycle and include sleep and wakefulness. Can be altered by
artificial light.
Sleep stages:
1. NREM 1: transition period between wakefulness and sleep; lasts about 5-10 minutes.
2. NREM 2: body temperature drops and heart rate begins to slow, brain begins to produce sleep
spindles; lasts 20 minutes.
3. NREM 3: muscles relax, blood pressure and breathing rate drops; deepest sleep.
4. REM: brain becomes more active, body becomes relax, dreams occur, eyes move rapidly.
Sleep disorders:
• Insomnia: ongoing difficulty falling or staying asleep.
• Narcolepsy: sudden attacks of overwhelming sleepiness.
• Sleep apnea: stops breathing repeatedly while sleeping.
• Sleepwalking/talking: talking or walking during NREM 3.
• Night terrors: sudden episodes of fear and aggression during sleep, screaming, but still sleeping
and not remembering this in the morning; occurs in non-REM sleep.
While nightmares are scary dreams that occur in REM sleep.
• REM sleep behavior disorder: acting out dreams during REM.
• Shift work: difficulty or feeling tired during work shifts.
• Jetlag: internal body clock change after traveling.
• Restless leg syndrome: prevents from falling asleep due to leg tremors.
Dreams:
Dreams have no meaning. When we sleep, our brain produces random dream images (activation) which
are combined by the brain into a story (synthesis).
Drugs:
1. Depressants: slow the body down.
Example: Alcohol, heroin, morphine, codeine.
2. Stimulants: pump the body up.
Example: caffeine, nicotine, cocaine.
3. Hallucinogens: mind-manifesting drugs that may distort perception.
Example: LSD, marijuana.
• Tolerance: repeated exposure to a drug makes the drug's effect lessen. It takes greater quantities
to get the desired effect.
• Dependence: absence of a drug may lead to a feeling of physical pain, intense cravings, and
negative emotions.
• Withdrawal: upon stopping the use of drug, users experience the undesirable effects.
