Chapter 3 - Biology and Behavior

Question 1

What does it mean to say that everything psychological is biological?

Answer 1

The mind and the brain is one thing. The mind is what the brain does.

Question 2

What are glial cells and what do they do?

Answer 2

They make up the myelin sheath.

Question 3

What are the basic parts of the neuron and what role does each of the parts play in the process of neural communication?

Answer 3

Dendrites - antenna on the neuron, increases the size of its receptive field
Cell body - has a nucleus inside, where information gets integrated, does computation
Axon - long skinny part, has myelin sheath. (made up of glial cells)
Myelin sheath - white coating on the outside of the axon, allows electricity to travel faster in neurons (not all neurons have myelin)
Terminal buttons - knoblike structures at the end of the axon

Question 4

Explain the basic processes underlying an action potential.

Answer 4

Resting Potential - the neuron is more negative in the inside compared to the outside (polarized)

When the neuron receives excitatory inputs it causes it causes more positive charge to come inside the neuron (depolarizing)

Once the neuron receives enough excitatory input, the neuron fires

This is an all or nothing response! The neuron either fires or it doesn’t

After the neuron fires, positive charges are pumped back outside the neuron (refractory period)

Absolute refractory period - a neuron can’t be fired

Relative refractory period - a neuron can be fired but it requires more excitatory input than before

Question 5

How do neurons send signals to other neurons?

Answer 5

Neurons communicate with other neurons at the synapse.
Synaptic vesicles release neurotransmitters and these neurotransmitters bind to specific receptors of a neighboring neuron.

Reuptake - when the neurotransmitter is taken back into the presynaptic terminal button (if you BLOCK this, you can get more effect of neurotransmitters)

Enzyme deactivation - when the enzyme destroys the neurotransmitter in the synapse.

Question 6

What does serotonin do?

Answer 6

Influences mood, sleep/wake cycle (dreaming), hunger, impulsiveness

Question 7

What does dopamine do?

Answer 7

Controls voluntary movement, heavily involved in reward feeling, learning/attention

Question 8

What does epinephrine and norepinephrine do?

Answer 8

Both involved in flight or fight response. Increases anxiety, alertness, heart rate, heat in your body

Question 9

What does acetylcholine do?

Answer 9

Motor control over muscles, learning, memory, sleeping, dreaming

Question 10

What does GABA (gamma-aminobutyric acid) do?

Answer 10

Inhibits action potential, reduces anxiety

Question 11

What does glutamate do?

Answer 11

Enhances action potential, facilitates learning and memory

Question 12

What do endorphins do?

Answer 12

Pain reduction, reward feeling

Question 13

What does methamphetamine do?

Answer 13

Huge hit of dopamine (very addicting!)

Question 14

What does ritalin do?

Answer 14

Affects dopamine by blocking reuptake. However, it is more of a subtle, slow, long term effect. Also, has an effect on norepinephrine (increases alterness)

Question 15

What does ecstasy do?

Answer 15

Affects dopamine and norepinephrine. Huge hit of serotonin

Question 16

What does sudafed do?

Answer 16

Affects ephedrine (“flight or flight” response), makes you jittery

Question 17

What does prozac do?

Answer 17

Serotonin rush by blocking reuptake. A type of SSRI (selective serotonin reuptake inhibitor)

Question 18

What is the importance of the brain stem?

Answer 18

The brain stem is necessary for survival. In charge of several basic functions such as breathing and urination.

Question 19

What is the function of the medulla?

Answer 19

Breathing and heart rate

Question 20

What is the function of the pons?

Answer 20

“Bridge”, bridges the cerebellum to the the brain stem, responsible for sleeping and dreaming

Question 21

What is the function of the reticular formation?

Answer 21

Pulls you into alertness, extends up to the thalamus

Question 22

What is the function of the cerebellum?

Answer 22

“Little brain”, coordinates movement

Question 23

What is the function of the thalamus?

Answer 23

Gateway for all incoming sensory information in your brain (except for smell). Helps shut down some sensory information while you sleep

Question 24

What is the function of the hypothalamus?

Answer 24

Regulator of your brain, thermostat (body temperature), circadian rhythm, blood pressure, etc.
4 Fs - Fleeing, Feeling, Flighting, Sex

Question 25

What is the function of the amygdala?

Answer 25

Memory, emotional responses (fear and aggression)

Question 26

What is the function of the hippocampus?

Answer 26

Directs/organizes memory, involved in forming NEW memories

Question 27

What are the 4 lobes of the cerebral cortex? What are there functions?

Answer 27

Occipital Lobe -

Question 28

What is the function of the primary visual cortex?

Question 29

What is the function of the somatosensory cortex?

Question 30

What is the function of Wernicke’s area? What happens if that area is damaged?

Question 31

What is the function of the prefrontal cortex?

Question 32

What is the function of the orbitofrontal cortex?

Question 33

What is the function of the primary motor cortex?

Question 34

What is the function of Broca’s area? What happens if that area is damaged?

Question 35

What is the function of the corpus callosum?

Answer 35

The connection between the left and right hemispheres.

Question 36

What has research with split brain patients told us about the nature of the two hemispheres of the brain?

Answer 36

When the corpus callosum is cut out, the two hemispheres do not receive information from each other. Split brain patients have given insight to the specialization of each hemisphere.

If a split-brain patient sees two pictures flashed on a screen briefly and simultaneously—one to the visual field’s right side and one to the left side—the patient will report that only the picture on the right was shown. This is because the left hemisphere, with its control over speech, sees only the picture on the right side. Since the right hemisphere has no language capacity, the right hemisphere has trouble saying the image it saw on the left side. However, since the right brain is good with spatial relationships, it can pick out the image it saw on the left side with its left hand.

Question 37

Describe how that research worked. In what ways are the right and left hemispheres different?

Answer 37

The left hemisphere is better with language, while the right hemisphere is better with spatial relationships.

Question 38

What are the basic units of the overall nervous system?

Answer 38

The nervous system is broken down into two divisions: the central nervous system (brain and the spinal cord) and the peripheral nervous system (all other nerves). The peripheral nervous system gets broken down even further into the somatic nervous system and the autonomic nervous system. And the autonomic nervous system gets broken down even further into the sympathetic and parasympathetic nervous system.

Question 39

How does the primary function of a sensory neuron differ from the primary function of a motor neuron?

Answer 39

Sensory neurons detect information from the physical world and pass that information along to the brain.
Motor neurons direct muscles to contract or relax, thereby producing movement.

Question 40

What is the difference between an agonist and an antagonist?

Answer 40

Agonist - “again”, increase the effect of neurotransmitters (ex: SSRIs)
Antagonist - “anti” decrease the effect of neurotransmitters

Question 41

What is the function of the insula?

Answer 41

Necessary for TASTE, gives you the ability to be aware of bodily states related to emotion (ex: your heart beating fast when you’re nervous)

Question 42

What is the function of the basal ganglia?

Answer 42

Planning and producing movement. Important for learning movement and habits. (ex: why you know to look for cars when you cross the street)

Question 43

What is the function of the nucleus accumbens?

Answer 43

Important for experiencing reward and motivating behavior (where DOPAMINE ACTIVITY occurs)

Question 44

How do the functions of the autonomic nervous system and the somatic nervous system differ?

Question 45

How do the functions of the sympathetic and parasympathetic systems differ?

Question 46

What is the difference between a genotype and a phenotype?

Question 47

What does it mean to say that a trait is polygenic?

Question 48

Explain the logic of twin studies.

Answer 48

Compare similarities between different types of twins to determine the genetic basis of specific traits. To the extent that monozygotic twins are more similar than dizygotic twins, the increased similarity is most likely due to genetic influence. GENES INFLUENCE PERSONALITY

Question 49

What does it mean to say that heritability is about a population and not about individuals?

Answer 49

This term refers to the proportion of the variation in some specific trait in a population that is due to genetics. RELEVANT to understanding the population as a whole, not just the individual.

Question 50

What does epigenetics mean?

Answer 50

Epigenetics researchers look at the processes by which environment affects genetic expression.
Ex: If you live in a poor community, some genes may be more expressed than others. These changes in how DNA is expressed can be passed along to future generations