psych 2

How is the title of a scholarly journal article usually different from the title of a book or

article for a general audience?

A scholarly journal article usually has a more specific and detailed title that clearly tells

you what the study is about. A title for a general audience is usually more catchy or

meant to grab your attention

What is the abstract of a journal article?

The abstract is a short summary of the entire article It gives you a quick idea of what the

study was about, what the researchers did, and what they found

What is in the literature review section of a journal article?

The literature review goes over previous research that has already been done on the topic.

It explains what researchers already know and how the current study connects to that

research

What is the difference between a hypothesis and a research question?

A hypothesis is a specific prediction about what the researcher thinks will happen. A

research question is what the researcher wants to find out and does not necessarily make

a prediction

What is in the methods section of a journal article?

The methods section explains how the study was done. It includes things like who

participated in the study, what materials or measures were used, and what the participants

had to do

Why is replication important?

Replication is important because it shows whether the same results can be found again. If

a study is repeated and gets similar results, it gives researchers more confidence that the

original findings were reliable

Why is it important to think about the potential demand characteristics of a study?

Demand characteristics can cause participants to figure out what the study is about and

change how they act because of it. This can affect the results and make them less

accurate

What is the issue of directionality? As part of your answer, you should explain how the

issue of directionality limits our ability to draw conclusions about cause and effect from

correlations

The issue of directionality means that when two things are correlated, we do not know

which one is causing the other. For example, stress could cause someone to sleep poorly,

but poor sleep could also cause more stress. Because we do not know which direction the

relationship goes, a correlation cannot prove cause and effect

Why can’t a third variable be a confounding variable if it only affects one of the two

variables in a correlation?

A third variable would have to affect both variables to explain why they are related. If it

only affects one of them, it cannot explain the correlation between the two variables

What is external validity?

External validity is how well the results of a study can apply to other people, situations,

or settings outside of the actual study

Why is it important for an experiment to have external validity?

It is important because researchers usually want their findings to apply outside of just the

specific people or setting they studied. If a study has good external validity, the results

are more likely to apply to real-life situations

Laura wanted to study whether a diet intervention emphasizing fruit, vegetables, and

protein improves the mood of people with depression. She recruited participants with

major depressive disorder and randomly assigned them to receive the dietary intervention

or a control condition. After three months, she measured all of the participants’

depression symptoms. “Wait,” asked John, “what if some of the participants were more

depressed than others at the start of the study? Wouldn’t that affect which group is more

depressed at the end?” Explain how the process of randomization addresses John’s

concern.

Random assignment gives each participant an equal chance of being put into either group.

Because of this, people with different levels of depression should be spread between the

two groups instead of all the more depressed people ending up in one group. This helps

make the groups more similar at the start of the study

What is statistical significance?

Statistical significance means that the results are unlikely to have happened just because

of random chance

Why does it make sense that having a larger sample would make it easier to find a

statistically significant result?

A larger sample gives researchers more information and makes the results less affected

by random differences between people This makes it easier to find a real difference or

relationship if there is one

Why does it make sense that studying a larger effect makes it easier to find a statistically

significant result?

A larger effect is easier to notice because the difference or relationship between the

variables is stronger This makes it easier to tell that the result probably did not happen

just because of random chance

What is in the discussion section of a journal article?

The discussion section explains what the results mean. Researchers talk about whether

the results supported their hypothesis or answered their research question, any limitations

of the study, and what could be studied in the future

What are chromosomes?

Chromosomes are long strings of genetic material made up of DNA

What is DNA?

DNA stands for deoxyribonucleic acid. It is a helix-shaped molecule made up of

nucleotide base pairs

What is a gene?

A gene is a sequence of DNA that controls or partially controls certain traits, like eye

color or hair color

What is an allele?

An allele is a specific version of a gene. For example, a gene can control hair color, while

different alleles affect which hair color a person has

How is a genotype different from a phenotype?

A genotype is a person’s genetic makeup. A phenotype is a person’s inherited and

observable characteristics, which are influenced by both genetics and the environment

What is a dominant allele?

A dominant allele is an allele that will show in a person’s phenotype if they have at least

one copy of it

What is a recessive allele?

A recessive allele is an allele that will only show in a person’s phenotype if they have two

copies of the recessive allele

How is a homozygous genotype different from a heterozygous genotype?

A homozygous genotype means someone has two copies of the same allele, like BB or

bb A heterozygous genotype means someone has two different alleles, like Bb

Why is it usually unhelpful to ask whether something is caused by “nature” or caused by

“nurture”?

It is usually unhelpful because most traits and behaviors are influenced by both genetics and the

environment. They work together, so it is usually not just one or the other

What is the difference between the study of molecular genetics and the study of behavioral

genetics?

Molecular genetics looks at specific genes and how they work. Behavioral genetics looks at how much

genes and the environment influence differences in behavior and traits between people

What is a family study?

A family study looks at whether a certain trait or behavior occurs more often among people who are

biologically related

What is the main problem with using a family study to conclude that a behavioral trait is

influenced by genetics?

Family members usually share both genes and an environment. Because of this, it is hard to know whether similarities are caused by genetics, the environment, or both

How are monozygotic twins different from dizygotic twins?

Monozygotic twins are identical twins that come from one fertilized egg and share almost 100% of their genes. Dizygotic twins are fraternal twins that come from two different eggs and share about 50% of their genes, like regular siblings

How do twin studies use the difference between monozygotic twins and dizygotic twins to try to figure out how much a behavioral trait is influenced by genetics?

Researchers compare how similar identical twins are to how similar fraternal twins are. If identical twins are much more similar for a trait than fraternal twins, that suggests genetics may have a stronger influence on that trait

How do adoption studies try to figure out how much a behavioral trait is influenced by genetics?

Adoption studies compare adopted children to their biological parents and their adoptive parents.

Similarities with biological parents suggest a genetic influence, while similarities with adoptive parents suggest an environmental influence

What have adoption studies found about criminal behavior?

Adoption studies suggest that criminal behavior can be influenced by both genetics and the environment A person may inherit a greater risk for certain behaviors, but their environment can also affect whether those behaviors actually develop

What have adoption studies found about intelligence?

Adoption studies suggest that intelligence is influenced by both genetics and environment. Adoptedchildren can resemble their biological parents in intelligence, but their adoptive environment also plays an important role

What have adoption studies found about alcoholism?

Adoption studies have found evidence for a genetic influence on alcoholism. Children of biological

parents with alcoholism can have an increased risk even when they are raised by adoptive parents who do not have alcoholism Environment still matters too

What are some problems with adoption studies that limit our ability to be certain that they tell us how much a trait is related to genes versus how much a trait is related to family life?

Adoptive families are not always randomly chosen, biological and adoptive families can sometimes have similar backgrounds, and children may have had experiences with their biological family before adoption Adoption agencies may also place children into families that are similar to their biological families

How does natural selection influence the prevalence of a trait in the population of a species?

If a trait helps an organism survive and reproduce, individuals with that trait are more likely to pass their genes on. Over generations, the trait can become more common in the population

Why do researchers sometimes study animals when they want to know something about

humans?

Animals share many biological and behavioral processes with humans. Researchers can also perform certain controlled studies with animals that would be impossible or unethical to do with humans

Researchers must justify the use of animals to their institution’s ethics board (the IRB). What arguments do they have to make to get their study approved?

Researchers have to show that using animals is necessary, that the research has enough potential scientific benefit to justify it, and that there is not a reasonable alternative. They also have to minimize the animals’ pain, stress, and suffering and properly care for them

What is evolutionary preparedness?

Evolutionary preparedness is the idea that organisms may be biologically prepared to learn certain

behaviors or associations because those behaviors helped their ancestors survive

Why do you think the words “evolutionary” and “preparedness” are used to define that

concept?

“Evolutionary” refers to the behavior developing through natural selection over many generations.

“Preparedness” means that an organism is already biologically more ready to learn certain things than others

What is altruism?

Altruism is behavior that helps another individual even when it involves a cost or risk to the person doing the helping

What is inclusive fitness?

Inclusive fitness is the idea that evolutionary success includes both producing your own offspring and helping genetically related people survive and reproduce

How might the concept of inclusive fitness explain how natural selection could promote the trait of altruism?

Helping relatives can help copies of your own genes survive because relatives share some of your genes Because of this, altruistic behavior toward relatives could be favored by natural selection

What is group selection?

Group selection is the idea that certain traits may become more common because they help the survival or success of the group as a whole

How might group selection promote the trait of altruism?

Groups containing more cooperative or altruistic members might survive or reproduce more successfully than groups whose members do not cooperate. This could allow altruistic traits to become more common over generations

On average, how do males and females differ in terms of promiscuity?

On average, males tend to show a greater tendency toward having multiple sexual partners than females. This is an average difference and does not mean every male or female behaves this way

How might natural selection promote Y chromosomes that lead to increased promiscuity?

A male could potentially produce offspring with multiple females in a relatively short period of time. If a genetically influenced tendency toward greater promiscuity resulted in more offspring, genes connected to that tendency could be passed on more often

On average, how do males and females differ in terms of the time and energy they devote to their offspring?

On average, females make a larger required biological investment in reproduction because of pregnancy and, in mammals, nursing. Males have a lower minimum biological investment, although actual parental involvement varies a lot between individuals and cultures

How might the principle of uncertain paternity explain why natural selection could increase the prevalence of Y chromosomes that promote a modest investment in a male’s offspring?

A mother is biologically certain that a child is her offspring, while historically a father could not have the same certainty of paternity. The idea is that natural selection could favor males who balance caring for offspring with other opportunities to reproduce rather than putting all of their time and energy into offspring whose genetic relationship to them was uncertain

What does it mean to say that a neuron’s outer surface is made of a semipermeable membrane?

It means the membrane lets some substances pass through while blocking others. Smaller molecules and molecules without an electrical charge can pass through more easily, while larger or highly charged molecules are blocked

What is soma?

The soma is the cell body of the neuron. It contains the neuron’s nucleus

What are dendrites?

Dendrites are branching extensions from the soma that receive signals from other neurons

What is the axon?

The axon is the long extension of a neuron that carries the electrical signal away from the cell body toward the terminal buttons

What are neurotransmitters?

Neurotransmitters are chemical messengers that neurons use to communicate with other neurons.

What is the function of the myelin sheath?

The myelin sheath is a fatty covering around the axon that acts as insulation and increases the speed at which the neuronal signal travels

What is the synaptic cleft?

The synaptic cleft is the tiny space between two neurons where neurotransmitters are released and communication between neurons occurs

What is the role of a dendrite’s receptors?

Receptors are proteins on the dendrite where specific neurotransmitters attach. The neurotransmitter and receptor work kind of like a lock and key, meaning certain neurotransmitters fit certain receptors

What is the resting potential?

The resting potential is the neuron’s state of readiness when it is not actively sending a signal. There is a difference in electrical charge between the inside and outside of the neuron

Why is the neuron membrane’s potential negative at rest?

The inside of the neuron is slightly negative compared to the outside partly because the sodium-potassium pump moves three sodium ions out of the cell for every two potassium ions it moves in

What is the action potential?

The action potential is the electrical signal that moves from the cell body down the axon toward the axon terminals

What does it mean to say that the action potential is an all or nothing phenomenon?

It means the neuron either reaches the threshold and fires completely or it does not fire at all. There is no partial action potential. Once it starts, it cannot be stopped

What is re-uptake?

Reuptake is when neurotransmitters in the synaptic cleft are taken back into the neuron that originally released them. This helps clear the synapse after the signal has been sent

What does the neurotransmitter dopamine do?

Dopamine is involved in mood, sleep, and learning. It is also associated with pleasure and can suppress appetite

What does the neurotransmitter GABA do?

GABA is involved in brain function and sleep It can decrease anxiety and tension

What does the neurotransmitter norepinephrine do?

Norepinephrine is involved with the heart, intestines, and alertness. It can increase arousal and suppress appetite

What does the neurotransmitter serotonin do?

Serotonin is involved in mood and sleep It helps regulate mood and can suppress appetite

What is an agonist?

An agonist is a chemical that mimics a neurotransmitter by binding to its receptor and producing a similar effect

What is an antagonist?

An antagonist is a chemical that blocks or interferes with the normal activity of a neurotransmitter at its receptor

What is the cerebral cortex?

The cerebral cortex is the outer surface of the brain. It is involved in higher-level processes like

consciousness, thought, emotion, reasoning, language, and memory

In what things does the right hemisphere of the brain tend to specialize?

The right hemisphere tends to be better at things like pitch perception, arousal, and negative emotions. It also controls the left side of the body

In what things does the left hemisphere of the brain tend to specialize?

The left hemisphere tends to be better at forming associations in memory, selective attention, and positive emotions. It also controls the right side of the body. The reading does point out that the two hemispheres work together and that research on strict left-versus-right specialization has sometimes been inconsistent

What is the corpus callosum?

The corpus callosum is a thick band of neural fibers that connects the left and right hemispheres. It allows the two sides of the brain to communicate and share information

What are the major functions of the frontal lobe?

The frontal lobe is involved in reasoning, motor control, emotion, and language. It also helps with

planning movement, higher-level thinking, judgment, impulse control, and producing language

What are the major functions of the parietal lobe?

The parietal lobe processes sensory information from the body, including touch, temperature, and pain

What are the major functions of the temporal lobe?

The temporal lobe is involved in hearing, memory, emotion, and some parts of language. It also contains Wernicke’s area which is important for understanding speech

What is the major function of the occipital lobe?

The occipital lobe mainly processes visual information It contains the primary visual cortex

What are the major functions of the thalamus?

The thalamus acts as a sensory relay center. Almost all sensory information, except smell, passes through the thalamus before being sent to other areas of the brain for processing

What are the major functions of the hippocampus?

The hippocampus is important for learning and memory, especially forming and consolidating new

explicit memories

What are the major functions of the amygdala?

The amygdala is involved in emotion and attaching emotional meaning to memories

What are the major functions of the hypothalamus?

The hypothalamus helps maintain homeostasis. It regulates things like body temperature, appetite, and blood pressure It also connects the nervous system with the endocrine system and is involved in sexual motivation and behavior

The medulla and the pons are part of the hindbrain. What do these parts of the hindbrain do?

The medulla controls automatic functions like breathing, blood pressure, and heart rate. The pons acts like a bridge connecting the hindbrain to the rest of the brain and also helps regulate brain activity during sleep

What are the major functions of the cerebellum?

The cerebellum helps control balance, coordination, movement, and motor skills. It is also involved in some types of memory, especially procedural memory, which is memory for how to perform task

Explain the sequence of the action potential

An action potential starts when a neuron is stimulated enough to reach a threshold. Then sodium

channels open and sodium rushes into the axon, making the inside more positive. After that,

sodium channels close and potassium channels open, so potassium leaves the cell and the inside

becomes negative again. The neuron briefly becomes even more negative than normal before

returning to its resting state

Why is the charge of the axon negative at rest?

At rest, the inside of the axon is negative compared to the outside because there are more

negatively charged particles inside the cell, and the neuron keeps more sodium outside and more

potassium inside. The sodium-potassium pump also helps maintain this difference in charge

How do voltage-gated ion channels work?

V oltage-gated ion channels open or close depending on changes in the electrical charge across

the cell membrane. During an action potential, these channels allow ions like sodium and

potassium to move in or out of the neuron

How does the size of an axon influence the speed at which messages pass through it?

Larger axons send signals faster than smaller axons. A larger axon has less resistance to the

electrical signal, so the message can travel through it more quickly

How does myelin influence the speed of neuronal transmission?

Myelin is a fatty covering around the axon that helps electrical signals travel faster. Instead of

moving continuously down the entire axon, the signal basically jumps from one gap in the

myelin to the next. These gaps are called nodes of Ranvier

What is a ligand-gated channel?

A ligand-gated channel is an ion channel that opens when a specific chemical, such as a

neurotransmitter, binds to it. When it opens, ions can move into or out of the neuron

Why does it make sense to call some neurotransmitters excitatory and some inhibitory?

Excitatory neurotransmitters make a neuron more likely to fire an action potential, while

inhibitory neurotransmitters make it less likely to fire. Basically, excitatory signals push the

neuron toward firing, while inhibitory signals hold it back

What is the cortical homunculus?

The cortical homunculus is a visual map showing how much of the brain's cortex is devoted to

sensing or controlling different parts of the body. Body parts that need more precise control or

have more sensation, like the hands, lips, and face, appear much larger on the map

What is sensation?

Sensation is when our sensory receptors detect information from the environment, like light,

sound, smell, or touch. Basically, it is the process of our senses picking something up

What is transduction?

Transduction is when sensory information, like light or sound, gets changed into electrical

signals that the nervous system and brain can understand

What is an absolute threshold?

An absolute threshold is the smallest amount of a stimulus that a person can detect 50% of the

time. So basically, how weak something can be before you stop noticing it

What is a just a noticeable difference?

A just noticeable difference, or JND, is the smallest difference between two stimuli that you are

able to notice. For example, how much louder a sound has to get before you can actually tell that

it got louder

How is perception different from sensation?

Sensation is actually detecting the stimulus, while perception is how your brain organizes and

interprets what you detected. So sensation is basically receiving the information, and perception

is making sense of it

What is sensory adaptation?

Sensory adaptation is when you stop noticing a stimulus after being exposed to it for a while.

The stimulus is still there, but your brain starts paying less attention to it. An example would be

getting used to a smell in a room after being there for a few minutes

According to signal detection theory, what influences whether we perceive a stimulus?

Whether we notice a stimulus depends on how well we can separate the actual stimulus from

background noise. Things like our attention, motivation, expectations, and the strength of the

stimulus can affect whether we notice it

What is the pupil?

The pupil is the opening in the eye that lets light enter. It gets bigger in darker conditions to let in

more light and smaller in brighter conditions

What is the function of the lens?

The lens helps focus light onto the retina. It can change its shape depending on whether you are

looking at something close up or far away

What is the function of the retina?

The retina is the light-sensitive layer in the back of the eye. It contains rods and cones that detect

light and start turning it into information that can be sent to the brain