Unit III - Biological Bases of Behavior Flashcards
1
Q
Why are psychologists concerned with human biology?
A
Psychologists from the biological perspective study the links between our biology and our behavior and mental processes.
2
Q
What is a neuron?
A
A nerve cell - basic building block of the nervous system
3
Q
What is the cell body or soma?
A
Part of the neuron - contains the nucleus, the cell’s life-support center
4
Q
What are the dendrites?
A
Bushy, branching extensions
Receive & integrate messages,
Conducting impulses toward cell body
5
Q
What is the axon?
A
Attached to the soma,
Neuron extension that passes messages through its branches to other neurons or to muscles or glands.
6
Q
What is the myelin sheath?
A
Fatty tissue layer segmentally encasing the axons of some neurons
Increases transmission speed and provides insulation
7
Q
What is myelin and why is it important?
A
Babies- no myelinated axons
Development not complete until age 25
Deterioration can lead to motor impairments (e.g. multiple sclerosis)
8
Q
What are the terminal branches?
A
Ends of axon containing terminal buttons
Hold synaptic vesicles that store neurotransmitters
9
Q
What are glial cells?
A
Cells that support, nourish, and protect neurons
Role in learning, thinking, and memory
10
Q
Neurons are like…
Glial cells are like
(hint:bee)
A
Queen bee- can’t perform any tasks
Worker bees- provide nutrients, insulation, guiding neural connections, clean up chemicals
11
Q
How is a neural impulse generated?
A
Combined received chemical signals exceed a minimum threshold, neuron fires transmitting an electrical impulse down axon
12
Q
What is a threshold?
A
The level of stimulation required to trigger a neural impulse.
Neurotransmitters received by the dendrites build up to initiate the action potential
13
Q
What is the all-or-none response?
A
More stimulation does not produce a more intense neural transmission
Neural rxn is all or nothing
Similar to gun, fire or don’t - squeezing trigger does not make bullet go faster
14
Q
Neural impulses can be…
A
excitatory or inhibitory
15
Q
What is an excitatory signal?
A
Like gas pedal on car
Signals trigger action
16
Q
What is an inhibitory signal?
A
Like the brake pedal on car
Signals depress action
17
Q
When excitatory impulses outnumber the inhibitory impulses,
A
threshold has been reached and an action potential occurs
18
Q
What is the resting state of an axon?
Polarized
A
Outside of axon’s membrane- positively charged sodium (Na+) ions
Inside of membrane- negatively charged proteins and small amount of positively charged (K+) ions
19
Q
What does it mean that an axon membrane is selectively permeable?
A
Membrane contains voltage gated ion channels that either open to allow ion exchange or close to prevent ion exchange
20
Q
What is the first step in an action potential?
A
first section of semipermeable axon opens its gates once threshold is met
Na+ ions flood in through the channels
21
Q
Why do Na+ ions rush in?
A
Since the inside of the membrane is slightly more negative, the Na+ ions try to balance the charge.
This causes a slight depolarization
22
Q
What is the second step in an action potential?
A
The depolarization changes the electrical charge of the next part of the axon.
Gates in this second area now open, allowing even more Na+ ions to flow in
23
Q
When Na+ ions move in, what happens to the K+ ions?
A
Gates open in first part of axon to allow K+ ions to flow out to repolarizes that section
24
Q
What is the third step in an action potential?
A
Sodium/potassium pump continues to depolarize new sections of axons/re-polarize the previous sections
25
How does impulse move?
The influx of the positive ions is the neural impulse.
The impulse moves down the axon like dominos falling one after the other.
26
What happens after the action potential moves to the end of the neuron??
Neurons need short breaks
REFRACTORY period- subsequent action potential can't occur until axon reaches resting state
27
What is polarization?
the resting state of the neuron, charge is more positive outside the membrane and more negative inside.
28
What is depolarization?
the action potential; the rushing in and out of positively charged ions
29
What is repolarization?
the refractory period; the closing of the membrane and reestablishing a more negative charge inside
30
How do neurons communicate with each other?
The sending neuron releases neurotransmitters across a synapse to the receiving neuron.
31
What is a neurotransmitter?
Chemical messengers that travel acorss the synapse and bind to the receptor sites on the receiving neuron
32
What is a synapse?
the junction between the axon tip of the sending neuron and the dendrite or cell body of the receiving neuron
33
What is the synaptic gap/cleft?
Tiny gap at this junction
34
When an action potential reaches an axon terminal branch,...
it stimulates the release of neurotransmitter molecules which cross the synaptic gap/bind to receptor sites on receiving neuron
35
Once a neuron receives neurotransmitters from another neuron's terminal branch,
this will either excite or inhibit a new action potential
36
What is reuptake?
A neurotransmitter's reabsorption by the sending neuron
37
Neurotransmitters have different
neutral pathways
38
Examples of neural pathways
serotonin pathway
| dopamine pathway
39
Acetylcholine neurotransmitter
Learning and memory
Messenger b/t motor neurons/skeletal muscles
Release causes muscle contractions
Blocked transmission causes paralysis
40
Dopamine Neurotransmitter
Undersupply of dopamine is linked to Parkinson's (suffered by Muhammad Ali)
Movement/learning/attention/emotion
Rewards/ addiction/ may lead to schizophrenia when in excess
41
What are endorphins?
Endogenous morphine
"Morphine within"
Natural opiate like neurotransmitters linked to pain control/pleasure
42
How do drugs alter neurotransmission ?
Drugs and chemicals from outside the body alter our brain chemistry.
Drugs act as agonists (exciting neuron firing) or as antagonists(inhibiting neuron firing).
43
How does an agonist work?
An agonist is a drug molecule that increases a neurotransmitter’s action.
44
How does an antagonist work?
An antagonist is a drug molecule that inhibits or blocks a neurotransmitter’s action.
Antagonists can also work by blocking reuptake
45
What is the nervous system?
body’s speedy, electrochemical communication network, consisting of all the nerve cells of the peripheral and central nervous systems
46
What are nerves?
bundled axons of many neurons that form neural cables connecting the central nervous system with muscles, glands, and sense organs.
47
What is an example of nerve?
Optic nerve bundles a million axons into a single cable carrying messages from the eye to the brain
48
What are the three types of neurons?
sensory (afferent), motor(efferent) and interneurons.
49
What are sensory neurons?
contain afferent nerve fibers
carry information from the sense organs to the CNS
50
What are motor neurons?
contain efferent neurons
carry messages from the CNS to the muscles and glands
51
How is the nervous system divided?
Peripheral
| Central
52
What systems are under the peripheral NS?
Autonomic
| Somatic
53
What is the Central Nervous System (CNS) and what does it do?
Brain and spinal cord.
The CNS is the decision maker responsible for coordinating incoming sensory messages and outgoing motor messages
54
What is the Peripheral Nervous System (PNS) and what does it do?
Sensory and motor neurons.
The PNS connects the body to the CNS by gathering information from the senses and transmitting messages from the CNS.
55
What does the somatic part of the PNS do?
controls the body’s skeletal muscles
also called the skeletal nervous system
56
What does the autonomic part of the PNS do?
controls the glands and the muscles of the internal organs (such as the heart)
operates automatically
57
What two parts are in the autonomic divsion?
Sympathetic
| Parasympathetic
58
What does the sympathetic nervous system do?
arouses the body, mobilizing its energy
fight, flight or freeze
The gas pedal of a car.
59
What does the parasympathetic nervous system do?
calms the body, conserving its energy
rest or digest
The brake pedal of a car
60
The sympathetic nervous system…
| HBDSC
```
accelerates heartbeat
raise blood pressure
slows digestion
raises blood sugar
cools the body
```
61
The parasympathetic nervous system…
| HBDWC
```
decelerates heartbeat
lowers blood pressure
stimulates digestion
processes waste
calms the body
```
62
What are the two parts of the CNS?
Brain
| Spinal cord
63
What and how does the brain function?
Comprised of the cortex and subcortical structures carrying out various functions
Nerves arranged into neural networks
Like people grouping in cities
64
What and how does the spinal cord function?
2-way connection between PNS and brain
Oversees the sensory and motor pathways of reflexes.
65
What is the first step in a reflex?
Sense receptors in the skin send signals up through the spinal cord via sensory (afferent) neurons.
66
What is the second step in a reflex?
Interneurons in the spinal cord receive the information from the sensory neurons and send signals back through motor neurons.
67
What is the third step in a reflex?
Motor (efferent) neurons connect to muscles in the body and direct movement.
68
How does a simple reflex occur?
A simple reflex ... like that to pain… occurs only in the spinal cord before information reaches the brain.
69
What is the endocrine system?
body’s “slow” chemical communication system
a set of glands that secrete hormones into the bloodstream
70
What is the difference between the nervous system and the endocrine system?
NS
Neurons release neurotransmitters
Neurotransmitters move across synapses
Neural transmission is nano-fast
“text message”
ES
Glands secrete hormones
Hormones move through the bloodstream
Hormonal secretion is slower
“email”
71
What are the adrenal glands?
When the sympathetic nervous system is activated (during a fight, flight, or freeze event), the adrenal glands release epinephrine and norepinephrine (adrenaline and noradrenaline) to energize the body.
72
Norepinephrine (noradrenaline) is both a
hormone and a neurotransmitter
Epinephrine (adrenaline) energizes the body, but norepinephrine (noradrenaline) is released in the PNS to calm the body.
73
What is the pituitary gland?
endocrine system’s most influential gland.
Directed by hypothalamus
regulate growth and control over other endocrine glands
74
The hypothalamus is part of...
both the CNS and the endocrine system
75
What are secreted from the pituitary gland?
```
Growth hormone
Growth/metabolism
Oxytocin: uterine contractions of childbirth
Milk secretion
Pair bonding
Group cohesion/trust
Direct other glands
```
76
How do scientists study the brain?
Lesion
| Stimulation
77
What is a lesion?
brain tissue is destroyed and researchers study the impact on functioning
78
What is a simulation?
Brain regions are stimulated electrically, chemically, or magnetically and researchers study the impact on functioning
79
How does EEG scans image the brain?
A recording of the waves of electrical activity across the brain’s surface measured by electrodes placed on the scalp.
80
How does MEG scans image the brain?
A brain imaging technique that measures magnetic fields from the brain’s natural electrical activity.
81
How does CT scans image the brain?
X-ray photographs taken from different angles and combined by computer to show
a slice of the brain’s structure; shows structural damage.
82
How does PET scans image the brain?
A visual display of brain activity that detects where a radioactive glucose goes while the brain performs a given task. Shows activity.
83
How does MRI scans image the brain?
A technique that uses magnetic fields and radio waves to produce computer-generated images of brain anatomy.
More detailed than CT scan.
84
How does fMRI scans image the brain?
A measure of blood flow and brain activity by comparing successive MRI scans to show brain function or as well as structure.
Shows damage.
85
Which imaging techniques show structure ?
CT
MRI
fMRI
86
Which imaging techniques indicate function?
EEG
MEG
PET
fMRI
87
Which structures make up the brainstem?
Pons
| Medulla
88
What are the functions of the medulla?
at the base of the brainstem
controls heartbeat and breathing
89
What are the functions of the pons?
just above the medulla
controls sleep and helps coordinate movements
90
What are the functions of the reticular formation?
nerve network that travels through the brainstem into the thalamus
helps control arousal and filters incoming sensory stimuli
91
What are the functions of the thalamus?
at the top of the brainstem
relay station for incoming and outgoing sensory information (with the exception of smell)
92
What are the functions of the cerebellum
at the rear of the brainstem
processing sensory input, coordinating movement and balance, nonverbal learning and memory
93
Which structures make up the limbic system?
Hypothalamus
Amygdala
Hippocampus
94
What are the functions of the amygdala?
two lima-bean-sized neural clusters
linked to emotion, fear, and aggression
95
What does research suggest about the functions of the amygdala?
Math anxiety-hyperactivity in right amygdala
Criminal behavior with amygdala dysfunction
Angry faces increase activity in amygdala
96
What are the functions of the hypothalamus?
below (hypo) the thalamus;
directs eating, drinking, body temperature
helps govern the endocrine system via the pituitary gland, linked to emotion and reward
97
What does research suggest about the functions of the hypothalamus?
Stimulating the reward centers of the hypothalamus will motivate a rat to cross an electrified grid, receiving painful electric shocks, to reach a bar that will give additional stimulation.
98
What are the functions of the hippocampus
Small structure with two “arms” that wrap around the thalamus
helps process for storage explicit (conscious) memories of facts and events
99
What does research suggest about the functions of the hippocampus?
No hippocampus= no new memories
Hippocampus tumor- struggle to retain information
Concussion-shrunken hippocampus/poor memory
100
What is the cerebral cortex?
intricate fabric of interconnected neural cells covering the cerebral hemispheres
the body’s ultimate control and information-processing center.
It is divided into four regions called lobes.
101
What four lobes make up the cerebral cortex?
frontal lobe, parietal lobe, temporal lobe and occipital lobe
located in both right and left hemispheres
102
What are the functions of the frontal lobes?
Involved in speaking, motor movements, judgment and decision- making.
103
What are the functions of the parietal lobes?
Receives and processes sensory input for touch and body position.
104
What are the functions of the temporal lobes?
Each lobe receives auditory information, primarily from opposite ear.
105
What are the functions of the occipital lobes?
Each lobe receives visual information, primarily from opposite visual field.
106
What are the functions of the motor cortex?
controls voluntary movements
107
What are the functions of the somatosensory cortex?
registers information from the skin senses and body movement
108
What are the functions of the auditory cortex?
receives information from the ears
109
What are the functions of the visual cortex?
receives information from the eyes
110
Do we really use only 10% of our brain
NOPE
90% is association areas
Smarter animals have larger association ares
111
What are the association areas?
Most of the brain’s cortex which integrates information involved in learning, remembering, thinking, and other higher-level functions.
Attention is shifted, planning occurs.
Not specifically devoted to motor or sensory cortex functions.
112
What does research say about association areas?
The prefrontal cortex in the forward part of the frontal lobes enables judgment, planning, and processing of new memories
Damage to this area-high IQ/great cake-baking skills
Bad memory/no planning skills
113
The case of Phineas Gage
A tamping iron accident damaged neural tracks in his frontal lobe.
His frontal lobes could no longer filter emotional reactions from the limbic system.
114
What are Broca’s areas?
language center located in the left frontal lobe
involved in expressive language
115
What are Wernicke’s areas?
language center located in the left temporal lobe
involved in receptive language
116
How does our brain adjust to new experiences?
plasticity: the brain’s ability to change, especially during childhood, by reorganizing after damage or by building new pathways based on experience
117
Give an example of plasticity.
Increased hippocampus in taxi drivers in London whom spent 2-4 years memorizing routes
118
How does plasticity work?
Removal of right hemisphere from little girl due to chronic seizures
Left hemispheres compensated by reallocation functions to other areas
119
What is neurogenesis?
Production of new neurons intended for self-repair
120
What is meant by a split brain?
The corpus callosum is a wide band of axon fibers connecting the two hemispheres
of the brain.
Split brain results when the fibers of the corpus callosum are severed isolating each hemisphere
from the other.
121
How are the eyes wired to the brain?
In each eye, information from the left visual field goes to your right hemisphere, and information
from the right half of your visual field goes to your left hemisphere.
122
What is a visual field?
Along the retina of the eye, sense receptors pick up stimuli that is about two inches apart – the right sides of both retinas gather information from the left side of what you are looking at and vice versa.
123
How is a split brain different from an intact brain?
Intact brain- info readily transferred across corpus callosum
Split brain-transfer does not occur
124
What was the first step in Michael Gazzaniga's experiment?
Patients with a severed corpus callosum (“split brain”) were asked to look at a dot in the center of a screen.
This created a left and right visual field.
125
What was the second step in Michael Gazzaniga's experiment?
The word “HEART” was flashed on the screen so that the word “HE” was in the left visual field and the word “ART” appeared in the right visual field.
126
What was the third step in Michael Gazzaniga's experiment?
Patients were asked to tell Gazzaniga what they had seen.
Patients reported seeing the word “ART”.
127
Why did the patients report seeing the word ART?
cross wiring-objects in the right visual field perceived in left hemisphere
Left hemisphere-Broca's and Wernicke's area- controls language
Patient said ART
128
What did the patients point to with their left hands?
Pointed to the word flashed in the left visual field
| Left hand controlled by right hemisphere
129
What are the function of the left hemispheres?
speaking and language
math calculations
making literal interpretations
controlling the right side of the body
130
What are the function of the right hemispheres?
```
perceptual tasks
making inferences
modulating speech
visual perception
recognition of emotion
controlling the left side of the body
```
131
Humans have two -- not two brains
Hemispheres
| ONE BRAIN WITH TWO HEMISPHERES
132
Are humans left or right-brained?
NOPE
| We use the entirety of our brain to perform countless activities
133
What is consciousness?
Our subjective awareness of ourselves and our environment.
Helps us cope with novelty and act in our best interests.
134
What is cognitive neuroscience?
Combines the study of brain activity with how we learn, think, remember and perceive.
Researchers are exploring and mapping the conscious functions of the cortex.
135
What is dual processing?
principle that information is often simultaneously processed on separate conscious and unconscious tracks.
136
The high road is ___, the low road___
Reflective
| Intuitive
137
What can be dually processed?
Perception,memory, thinking, language, and attitudes
138
What is blindsight?
A condition in which a person can respond to a visual stimulus without consciously experiencing it
139
What is parallel processing?
unconscious processing of many aspects of a problem simultaneously
generally used to process well-learned information or to solve easy problems
140
What is sequential processing?
conscious processing or one aspect of a problem at a time
generally used to process new information or to solve difficult problem
141
How does heredity differ from environment?
Heredity- genetic transfer of characteristics from parent to offspring
Environment-every nongenetic influence, from prenatal nutrition to the people and thing around us
142
What do behavior geneticists study?
relative power and limits of heredity and environmental influences on behavior.
143
What is a chromosome?
Threadlike structures made of DNA molecules that contain the genes.
Each person has 46 chromosomes – 23 from each parents
144
What is DNA?
complex molecule containing the genetic information that makes up the chromosomes.
145
What are genes?
biochemical units of heredity that make up the chromosomes;
segments of DNA capable of synthesizing proteins.
You have ~20,000 genes.
146
What is the human genome?
complete instructions for making a human organism, consisting of all the genetic material in that human’s chromosomes.
Common sequence within human DNA- shared genetic profiles distinguishes us as humans
147
How do monozygotic twins develop?
Identical monozygotic twins
Single fertilized egg splits into two, creating two genetically identical organisms
148
How do dizygotic twins develop?
Fraternal dizygotic twins
separate fertilized eggs that share a maternal prenatal environment… no more alike than siblings
149
How do MZ and DZ twin studies help us understand nature and nurture?
A person whose identical twin has autism spectrum disorder has about a 3 in 4 risk of being similarly diagnosed. If the affected twin is fraternal, the co-twin has about a 1 in 3 risk.
Identical twins are much more alike in extraversion (outgoingness) and neuroticism (emotional instability) than are fraternal twins.
Drinking and driving convictions are 12 times greater among those who have an identical twin than those with a fraternal twin with such a conviction.
150
What do twins reared apart tell us about heredity and environment?
Thomas Bouchard et al located and studied 74 pairs off identical twins raised apart-similarities of tastes, physical attributes personality, abilities, attitudes, interests, and feats
151
How do adoption studies help us understand nature and nurture?
Two adopted children raised in the same home are no more likely to share personality traits with each other than with the child down the block.
The environment shared by a family’s children has virtually no discernible impact on their personalities
152
What is heritability?
Variation of heritability depends on what?
proportion of variation among individuals in a group that we can attribute to genes.
The heritability of a trait may vary, depending on the range of populations and environments studied.
153
Give examples of heritability of a trait.
Personality traits are ~40% heritable
Intelligence is ~60% heritable.
Height is ~90% heritable.
154
What does “intelligence is about 60% heritable” mean…and NOT mean?
Genetic influence explains about 60% of the observed variation among people.
DOES NOT MEAN: Your intelligence is 60% genetic
155
Teasing apart environment from genetics
Raising boys in barrels to age 12 feeding them through a hole- lower than average IQ
Yet, given their equal environments, their test score differences could be explained only by their heredity.
156
How do similar environments impact heritability?
If the differences due to environment would decrease, heritability would increase
Any difference we noticed between two students would then be generalized more to their genes than environment
157
What is molecular genetics?
the study of the molecular structure and function of genes
158
What is molecular behavior genetics?
the further study of how the structure and function of genes interact with our environment to influence behavior
159
What is epigenetics?
| "Above genetics"
Study of environmental influences on gene expression that occur without a DNA change
how an individual’s lifestyle, environment, choices, etc. can directly interact with the genome.
160
How does epigenetics influence gene expression?
life experiences lay down epigenetic marks—often organic methyl molecules—that can affect the expression of any gene in the DNA segment they affect.
161
What are some examples of epigenetics research?
effects of trauma, poverty, malnutrition last lifetime
Health affected by stresses or pollutants experienced by grandparents
Why one member of MZ may develop genetically influenced mental disorder
162
How do evolutionary psychologists use natural selection to explain behavior?
Darwin’s principles of natural selection guide evolutionary psychologists in understanding what makes humans so much alike.
163
What is natural selection?
principle that inherited traits that better enable an organism to survive and reproduce in a particular environment will (in competition with other trait variations) most likely be passed on to succeeding generations
164
What is a mutation?
a random error in gene replication that leads to a change
165
What are Darwin’s basic principles?
Organisms’ varied offspring compete for survival.
Certain biological and behavioral variations increase organisms’ survival chances in their particular environment
Offspring that survive are more likely to pass their genes to the next generation.
Over time population characteristics may change.
166
Researchers Belyaev and Trut selectively bred the tamest foxes over many generations
after 40 years were able to produced domesticated animals
Psychological traits can be selected as well as physical traits
167
What about naturally occurring selection?
Our historical genes give us a great capacity to learn and to adapt to life in varied environments, from the tundra to the jungle.
Genes and experience together wire the brain.
Our adaptive flexibility in responding to different environments contributes to our fitness—our ability to survive and reproduce.
168
What do evolutionary psychologists believe about male sexuality?
May be more likely to initiate sexual activity.
| May perceive women’s friendliness for sexual interest.
169
What do evolutionary psychologists believe about female sexuality?
Tendency toward tall men with slim waists and broad shoulders.
May prefer men who are mature, dominant and bold.
170
What are social scripts?
a culturally modeled guide for how to act in various situations
171
Give examples of social scripts.
how to go out to eat in a restaurant (enter, take a seat, read a menu, order, eat, pay the bill, leave)
and social scripts that give indications of how men and women, elderly and young, etc., might act in a society.
172
Criticism of the evolutionary perspective on sexuality…
Start with the effect and work backward to explain what happened.
Try to explain today’s behavior with decisions made thousands of years ago.
There are social consequences to accepting evolutionary explanations.
173
How do evolutionary psychologists respond to this criticism?
Much of who we are is NOT hardwired…genes are NOT destiny.
Men and women are far more alike than different.
Some traits and behaviors are hard to explain in terms of natural selection.
174
What is the biopsychosocial approach to development?
Genes, environment and our culture all combine to influence our development.
