Chapter 1 Flashcards
1
Q
Biological Psychology
A
Study of the biological bases of psychological processes and behavior
Relates behavior to bodily processes
Goal: Understand biology underlying behavior & experience
aka Behavioral Neuroscience
2
Q
Neuroscience
A
Study of the nervous system and brain
3
Q
Interactions between brain and behavior are…
A
recipricol
4
Q
5 Major perspectives to understand biological basis of behavior
A
DESCRIBING behavior (correlation)
Studying EVOLUTION of behavior (cross species pespective)
Observing DEVELOPMENT of behavior& biological characteristics over life span
Study biological MECHANISMS of behavior (lesion studies)
Study APPLICATIONS of biological psychology (create interventions once understand)
5
Q
2 Emphases from Darwin’s theory of evolution
compare species in order to study evolution of brain and behavior
A
CONTINUITY of behavior & biological proccesses (result of common ancestor among species)
SPECIES-SPECIFIC DIFFERENCES in behavior & bio that’ve evolved as adaptions to diff environments
6
Q
conserved
A
reffering to a trait that’s passed on from a common ancestor to 2+ species
7
Q
ontogeny
A
process where an individual changes in the course of its lifetime
grows up & grows old
observing this gives clues to individual’s functions & mechanisms (can then speculate on bigger picture)
8
Q
devlopment
A
behaviors that change over the lifespan
9
Q
convergent evolution
A
similar appearances that come from species that have evolved independently and dont share a common ancestor
10
Q
Major aim of biological psychology
A
examine body mechanisms that make particular behaviors possible
11
Q
3 approaches used by behavioral psychologists to understand the relationship between brain & behavior
A
Somatic intervention
Behavioral intervention
Correlation
12
Q
Somatic Intervention
A
Manipulating body structure or function & looking for resulting changes in behavior
Most common approach to finding relations between body + behavior
Somatic intervention= independent var
Behavioral affect= dependent var
“Manipulating body-may affect behavior”
ex: hormone given to some animals, but not others & then behaviors of 2 groups are compared
13
Q
Independent variable
A
factor manipulated by experimenter
Must have 2+ levels (control, experimental)
14
Q
Dependent variable
A
factor that experimenter measures to monitor a change in response to the manipulation of independent var
changes based on independent variable
MEASURE IT
15
Q
main question of biological psychology
A
look for connections between brain and behavior
16
Q
behavioral intervention
A
Intervening in the behavior of an organism & looking for resultant changes in body structure or function
“experience affects the body”
psychological intervention
approach to finding relations between body and behavior
opposite of somatic intervention
behavior = independent var
change in body= dependent var
ex: expose person to visual stimulus provokes changes in electrical activity and blood flow
17
Q
correlation
A
find extent to which given body measure varies with a given behavioral measure
“covariation”
no proof of causal relationship or direction of correlation
ex: are people with larger brains more intelligent than people with smaller ones
18
Q
how can experience affect neurons
A
can affect the number size of neurons OR connections between them
19
Q
neuroplasticity
A
ability of nervous system to change in response to experience or the environment
(during development and adulthood)
other individuals can affect the physical structure of brain
ex: dendritic spines changing shape in seconds
20
Q
how does social experience affect brain structure
A
socially induced psychological expectation affects the magnitude of the brain response
(what you’re told before touching hot water)
21
Q
reductionism
A
scientific strategy
break system down into increasingly smaller parts in order to understand it
(closer and closer to atomic/molecular level)
22
Q
levels of analysis
A
scientist may use these to try and understand behavior (reductionsism)... social organ neural systems brain region circut cellular synaptic molecular
23
Q
how many people in the world suffer from psychiatric and neurological disorders
A
1/5
24
Q
what percent of lab rats make up the mammals used in research
A
93%
25
what'd they do to brains in olden times
threw it out because only considered it to be a cooling unit, heart was seen as source of mental act
early egyptian + greek scholars
26
Renaissance anatomist...
emphasized shape and appearance of external surface of brain
artists
start to see brain as maybe important
27
Descartes
concept of pineal gland relating mind and body
saw brain as machine
proposed concept of spinal reflexes and their neural pathways
didnt make claims public out of fear
28
dualism
Descartes
| nonmaterial soul & material body
29
phrenology
belief that bumps on the skull reflect enlargements of brain regions responsible for certain behavioral functions
concept of localization of specific brain functions
19th cent
30
Broca
when finally began to accept concept of localization
broca showed that language ability is restricted to a small area,
based on patient with damage in that region
lesion studies are important to localization
31
consciousness
State of awareness of one's own existence and experience
topmost parts of brain are responsible for what we experience moment to moment
permits us to plan
deepest parts of brain are important for arousal
32
fundamental attribution error
when we do something, blame what we did on external factors
| for others' actions, we blame it on who they are as a person
33
neuron
Nerve cell
Basic Unit of the nervous system
Contacts other neurons at synapses
Composed of a cell body, dendrite (receptive extensions), & an axon (transmitting ext)
receives inputs, integrates them, & distributes processed info to others
Function: to talk to other neurons
34
glial cells
non-neuronal brain cells
provide structural & nutritional support to the brain & neurons
make additional contributions to info processing
increase the strength of the postsynaptic potential
35
Golgi neuron thought
they're continuous with one another
| form a nearly endless network of connected tubes through which info flowed
36
Cajal's thought about neurons
come very close to one another, but not quite continuous
| at each point of contact between neurons, a tiny gap keeps cells seperate
37
neuron doctrine
hypothesis that the brain is composed of separate neurons that are distinct structurally, metabolically, & functionally
composed of independent cells
information is transmitted from cell to cell across tiny gaps/ synapses
emerged from Golgi & Cajal's studies
38
synapse
tiny gap between neurons
where information is passed from one to the other
demonstrated and named by Sir Charles Sherrington
human brain has 10^5 synapses
39
Neuron's 4 structural divisions specialized for information proessing
Input zone
Integration Zone
Conduction zone
Output zone
40
mitochondrion
cellular organellein neuron
| provides metabolic energy for cell's processes
41
neuron's contain
mitochondria
cell nucleus
ribosomes
42
cell nucleus
spherical central structure of a cell
contains the chromosomes & genetic instructions
organelle in the nucleus
43
ribosomes
structures in the cell body
where genetic information is translated to produce proteins
organelle in the nucleus
44
dendrites
```
one of the extensions of the cell body
are the receptive surfaces of the neuron
serve as an INPUT ZONE
synapse lands on dendrites
increase receptive surface of neuron & increase amount of info it can take in
```
45
input zone
part of neuron specialized for info processing
RECEIVES INFO from other neurons of specialized sensory structures
corresponds to cell's dendrites
46
cell body
region of neuron
defined by the presence of the cell nucleus
INTEGRATION ZONE
aka soma
47
integration zone
part of neuron specialized for info processing
initiates nerve electrical activity
where inputs are combines & transformed
corresponds to axon hillock
48
Structures present in all neurons
dendrite
cell body
axon terminal
axon hillock
49
axon hilllock
```
part of neuron
start of axon
where cell decides whether or not it will have an action potential
where action potential will start
INTEGRATION ZONE
```
50
axon
single extension from the neuron
carries nerve impulses from cell body to other neurons
leads away from cell body
CONDUCTION ZONE
51
conduction zone
part of neuron specialized for info processing
where nerve's electrical signal may be actively propagated
transmit's cells output information in form of electrical impulses
corresponds to cell's axon
52
axon terminal
part of a neuron
forms a synapse on a neuron or other target cell
specialized swelling at axon end
OUTPUT ZONE
53
output zone
part of neuron specialized for info processing
where cell sends information to another cell
transmits neuron's activity to other cells at synapses
corresponds to axon terminals
54
2 traditional cell stains
golgi stains
| nissl stains
55
golgi stain
first technique available
histological stain
fills small portion of neurons with a dark silver based precipitate (stains 1-3% of neuron)
includes details like dendritic spines
tells about overall structure, but misses number
useful to identify: type and shape of cells
56
histology
microscopic analysis of cells and tissues
57
nissl stain
histological stain
outlines all cell bodies
dyes are attracted to RNA, which encircles the nucleus
used to measure cell body size & density of cells
ex: How many neurons in one area of brain?
58
autoradiography
histological technique
shows the distribution of radioactive chemicals in tissues
cells are manipulated into taking pics of themselves
can be done in vitro or in viro (alive or dead)
can quantify receptors in tissue
59
immunocytochemistry
method for detecting particular protein in tissues
antibody recognizes and binds to protein
chemical methods used to leave visible reaction product around each antibody
is a way to label cells with an attribute in common
reveals only the cells that were making the specific protein
shows where current proteins are active
60
in situ hybridization
finds neurons w specific mRNA sequences
method for detecting particular RNA transcripts in tissue sections
use nucleotide probe (complementary to + will hybridize w transcript of interest)
uses radioactively labeled lengths of nucleic acid
61
immediate early genes (IEG)
genes that show rapid but transient increases in expression in cells that've just become activated
find where site of learning is
identifies brain regions active during certain behaviors
ex: c-fos
62
c-fos
immediate early gene
| commonly used to identify activated neurons
63
Santiago Ramon and Canal
first to use stain technique to investigate
| known for drawings using golgi stain
64
why it's difficult to trace pathways in the nervous system
fibers w different destinations travel together (hard to detangle one set from rest)
axons have smaller diameter than cell bodies
axons from different sources look alike
billions of axons in brain
65
common ways to trace pathways in the brain
damage neuron of interest & look for degenerating axons
inject radioactively labeled amino acids into collection of cell bodies
horseradish peroxidase (HRP)
anterogade labeling
retrograde labeliing
66
horseradish peroxidase (HRP)
enzyme found in horseradish
used to determine cells of origin of a particular set of axons
tract tracer
a trace pathway in the brain
67
anterograde labeling
radioactive molecules are taken up by cell, incorporated into proteins, & transported to tips of axons
used if want to know what a specific area is connected to
a trace pathway in the brain
68
retrograde labeling
tract tracer is taken up into the axon at the terminals & transported back to cell body where it's readily visualized
uses horseradish perioxidase
used to see all of the different areas communicating with one area
a trace pathway in the brain
69
transsynapticly
jump across synapses
| work their way "upstream" back toward higher levels of the nervous system
70
ways neurons can be classified
by shape, size, function
71
3 principal types of nerve cells
```
way to classify neurons by shape
multipolar
bipolar
unipolar
in all 3 types, the dendrites are in the input zone
```
72
multipolar neuron
most common type
many dendrites
single axon
73
bipolar neurons
single dendrite at one end
single axon at other end of cell
common in sensory systems (vision)
74
unipolar neuron
single extension that branches in 2 directions after leaving cell body (thought of as axon)
(one end input zone, other end is output zone)
transmits touch information from body to spinal cord
75
3 ways to classify by neuron function
motoneurons
sensory neurons
interneurons
76
motoneurons
nerve cell that transmits motor messages stimulating a muscle or gland
have long axons reaching out to synapse on muscles which cause them to contract in response to commands from the brain
77
quasi independent variable
something the experimenter is not fully in control of that can affect the dependent variable
78
operational definition
define construct in a way that allows us to manipulate or measure it
79
how can behavior be described
in terms of acts/ processes
| in terms of results/functions
80
difference between ontogeny & neural plasticity
ontogeny: changes for all across lifespan
| neural plasticity: changes to some individuals due to specific experiences
81
sensory neurons
neuron that's directly affected by changes in the environment
(light, odor, touch)
carry message from periphery --> spinal cord + brain
diverse shapes
82
interneuron
receives input and sends output to other neurons
majority of neurons
make up the hugely complex networks and circuits that perform the complex functions of the brain
axons are short
83
arborization
elaborate branching of the dendrites of some neurons
| reflects the complexity of the neuron's info processing system
84
presynaptic
reffering to region of the synase that releases neurotransmitter
85
postsynaptic
refferring to the region of a synapse that recieves and responds to neurotransmitter
86
3 principal components of a synapse
presynaptic membrane
postsynaptic membrane
synaptic cleft
87
presynaptic membrane
specialized membrane
on axon terminal of the neuron
transmits information by releasing neurotransmitter
88
postsynaptic membrane
specialized membrane
on the surface of the cell
receives info by responding to neurotransmitter from presynaptic neuron
lies on surface of dendrite/ cell body of postsynaptic neuron
89
synaptic cleft
space between the presynaptic and postsynaptic elements
90
synaptic vesicles
small, spherical structure that contains molecules of neurotransmitter
91
neurotransmitter
chemical released from the presynaptic axon terminal
serves as the basis of communication between neurons
communicates w postsynaptic cell
used to produce electrical changes in postsynaptic neuron
92
receptor
protein that binds & reacts to molecules of a neurotransmitter or hormone
released neurotransmitter interacts with postsynaptic recpetors after crossing cleft
93
effect of neurotransmitter interacting with postsynaptic receptor
=electrical changes in postsynaptic cell
| = affects likelihood of postsynaptic neuron releasing own neurotransmitter
94
contains high density of receptors
postsynaptic membrane
95
neural plasticity
ability of the nervous system to change in response to experience or the environment
configuration of synapses on neuron's dendrites & cell body is constantly changing
allows number & structure of dendrite spines to be rapidly altered by experience
96
axon hillock
cone-shaped area
from which the axon originates out of the cell body
functionally the integration zone of the neuron (gathers info from all synapses)
97
axon collateral
branch of an axon from a single neuron
| allows neuron to influence many presynaptic cells
98
innervate
provide neural input/influence
99
dendritic spine
studded on dendrites & increase surface area
100
axonal transport
transportation of materials from the
neuronal cell body to distant regions in the dendrites + axon
& from axon terminals back to the cell body
transports materials both ways
101
2 different functions of axons
rapid transmission of electical signals along the outside of axon
slower transportation of substances inside the axon
102
axons versus dendrites
```
AXON
one per neuron w many terminal branches
uniform diameter until branches
axon hillock
covered w myelin
range from tiny to several meters long
```
```
DENDRITE
many per neuron
diameter tapers progressively toward end
no axon hillock or myelin sheath
much shorter than axons
```
103
glial cells affect neuronal functioning
communicate with each other + other neurons
provide neurons w raw materials & chemical signals that alter neuronal structure
insulate + isolate synapses to prevent one from affecting the other
104
4 forms of glial cells
astrocyte
microglial cell
oligodendrocytes
schwann cells
105
astrocyte
star shaped glial cell
has numerous extensions that run in all directions, weaving among neurons
recieve synapses directly from neurons
surround + monitor activity of nearby neuronal synapses & recieve neuronal input
communicate w neurons to modulate the neuron's responses
involved in formation of new synapses
106
microglial cell
extremely small glial cells
remove cellular debris from injured or dead cells
"brain's cleanup crew" & damage control
key component of neural pain systems
107
oligodendrocyte
type of glial cell
forms myelin in the central nervous system
performs myelination within brain & spinal cord
provides myelin beads to many nearby axons
108
schwann cell
glial cell
forms myelin in the peripheral nervous system
perfroms myelination in rest of body (not brain + spinal cord)
109
myelination
process of myelin formation
glial cells wrap sections of axon in layers of myelin, giving it the appearence of a string of slender beads
causes large increase in speed that electrical signals pass down the axon
occurs for 10-15 years after birth
110
myelin
fatty insulation around an axon
formed by glial cells
improves the speed of conduction of nerve impulses
111
nodes of Ranvier
gap between successive segments of the myelin sheath where the axon membrane is exposed
the uninsulated patches
between adjacent beads
112
edema
swelling of the tissue in response to injury, especally in the brain
how astrocytes respond to brian injury
this damages neurons and is responsible for many symptoms of brain injuries
113
multiple scelerosis
"many scars"
disorder characterized by widespread degeneration of myelin
causes axons to lose outer insulation
114
gross neuroanatomy
anatomical features of the nervous system that are apparent to the naked eye
115
peripheral nervous system
portion of nervous system that includes all the nerves + neurons outside the brain and spinal cord
contains nerves
116
central nervous system
portion of the nervous system that includes the brain and spinal cord
117
nerves
collection of axons bundled together outside the central nervous system
118
motor nerve
nerve that conveys neural activity to muscle tissue & causes it to contract
info from spinal cord + brain --> muscles, organs, glands
119
sensory nerves
nerve that conveys sensory info from the peripheral
--> central nervous system
info from body --> brain + spinal cord
120
3 peripheral nervous system's nerves
cranial nerves
spinal nerves
autonomic nervous system
121
cranial nerves
nerve that's connected directly to the brain
nerve of peripheral nervous system
12 pairs
some primarily sensory & others motor
122
spinal nerves
nerve that emerges from the spinal cord
aka somatic
nerve of peripheral nervous system
31 pairs
123
autonomic nervous system
part of the peripheral nervous system
supplies neural connections to glands & smooth muscles of internal organs
nerves that primarily control the internal organs
124
autonomic ganglia
collections s of nerve cell bodies that are found in various locations & innervate the major organs
belong to autonomic division of peripheral nervous system
125
preganglionic
referring to neurons in the autonomic nervous system that run from
CNS --> autonomic ganglia
126
postganglionic
referring to neurons in autonomic nervous system that run from
autonomic ganglia --> various targets in the body
127
3 major divisions of autonomic nervous system
sympathetic nervous system
parasympathetic nervous system
enteric nervous system
128
sympathetic nervous system
part of the autonomic nervous system
arises from thoracic & lumbar spinal cord
send axons short distance
innervates sympathetic chain of autonomic ganglia
uses norepinephrine (no rest)
prepares body for action (heart rate quickens, blood pressure increase)
stimulates ejaculation
STAND UP
fight or flight
129
sympathetic chain
chain of ganglia that run along each side of the spinal column
part of sympathetic nervous system
postganglionic cells of synaptic chain course through body and innervate all major organ systems
130
parasympathetic nervous system
```
part of the autonomic nervous system
arises from both cranial nerves + sacral spinal cord
helps body to relax, recuperate
axons travell a longer distance before terminating in parasympathetic ganglia
uses acetylcholine (ace sleep)
stimulates erection
PAIR OF SOUP
rest and digest
```
131
what parasympathetic ganglia do in comparison to sympathetic
parasympathetic ganglia not collected in a chain, they are dispersed throughout body
132
norepinephrine
no rest
neurotransmitter
produced & released by sympathetic postganglionic neurons
used to accelerate organ activity
also produced in brainstem + found in projections throughout brain
133
acetylcholine
ace sleep
neurotransmitter produced & released by parasympathetic postganglionic neurons, motor neurons, & neurons throughout the brain
tends to slow down activity
134
enteric nervous system
part of autonomic nervous system
extensive meshlike system of neurons that governs the functioning of the gut
sensory and motor neurons
under the control of the CNS
plays key role in maintaining fluid & nutrient balances in the body
135
spinal cord's job
funnel sensory info from body to brain
convey brain's motor commands out to body
contains circuits that perform local processing & control simple units of behavior
136
cerebral hemispheres
right and left halves of the forebrain
137
cerebral cortex
outer covering of the cerebral hemispheres
consists largely of nerve cell bodies & their branches
causes lumpy convolutions of the cerebral hemispheres
made up of neurons + fibers
138
gyrus
rigid or raised portion of a convoluted brain surface
| folding greatly increases cortical surface area
139
sulcus
grooves in the convoluted brain surface
| seperates gyrus from each other
140
major cortical regions
```
frontal
parietal
temporal
occipital
named after bones of skull that overrides them
```
141
frontal lobe
most anterior portion of cerebral cortex
| higher level cognition and movement
142
parietal lobe
large regions of cortex lying between frontal + occipital lobes of each cerebral hemisphere
sensory info from body & spatial recognition & attention
where info is incorporated from other lobes
143
temporal lobe
large lateral cortical regions of each cerebral hemisphere
separated from frontal lobe by sylvian fissure
continuous with parietal lobes posteriorly
auditory info, sense of smell
144
occipital lobe
large regions of cortex covering much of the posteriror part of each cerebral hemisphere
receive & process info from eyes
team leader of visual stimuli
145
sylvian fissure
deep fissure that demarcates the temporal lobe
| temporal lobe boundary from others
146
central sulcus
fissure that divides the frontal lobe from the parietal lobe
groove in between
147
cortical damage causes
memory problem
speech error
personality change
visual impairment
148
postcentral gyrus
strip of parietal cortex
behind central sulcus
recieves somatosensory info from entire body
sense of touch
149
precentral gyrus
strip of frontal cortex
in front of central sulcus
crucial for motor control
contains an orderly map of the muscles of the body
150
corpus callosum
main band of axons that connects the two cerebral hemispheres
c shaped bundle of axons
enables communication between right and left cerebral hemispheres
151
white matter
shiny layer underneath the cortex
consists largely of axons with white myelin sheaths
consists mostly of fiber tracts
transmits information
152
gray matter
areas of the brain that're dominated by cell bodies
have no myelin
nerve cell bodies and dendrites
process information
153
forebrain
anterior division of brain
contains cerebral hemispheres & thalamus & hypothalamus
prosencephalon
split into telencephalon & diencephalon
154
midbrain
middle division of brain
| mesencephalon
155
hindbrain
rear division of the brain
| contains cerebellum & pons & medulla
156
when have forebrain and hindbrain developed clear subdivisions
50 days after conception
157
telencephalon
frontal subdivision of the forebrain
includes cerebral hemispheres when fully developed
cortex & basal ganglia & limbic system
158
diencephalon
posterior part of forebrain
| includes thalamus & hypothalamus
159
metencephalon
subdivision of the hind brain
| includes cerebellum & pons
160
cerebellum
located in back of brain behind pons
involved in central regulation of ovement
involved in coordination and movement
has 3 layers
161
pons
portion of metencephalon (hind brain)
part of brainstem
connects midbrain to medulla
162
medulla
posterior part of hind brain
continuous with spinal cord
contains nuclei that control breathing and heart rate
marks transition from brain to spinal cord
aka myelencphalon
163
brainstem
consists of midbrain, pons, medulla
164
5 main sections hind brain & fore brain divide into
"phalon"
telencephalon- frontal of fore (cerebral hemi, lmbic system, cortex, basal ganglia)
dilencephalon- posterior of fore (thal & hypothalamus)
mesenephalon- midbrain
metencephalon- divison of hind (cerebellum, pons)
myelencephalon- medulla
165
nucleus
collection of neurons within CNS
within and between major brain regions
same from individual to individual and species to species
166
tracts
bundle of axons found within CNS
| same from individual to individual and species to species
167
how are brains symmetrical
bilaterally symmetrical
| mirror images left and right
168
arrangement of neurons in cerebral cortex
6 distinct layers
4 mm thick
each is distinct cause it has a particular pattern of dendrites/axons or band of similar neurons
169
allocortex
brain tissue with 3 layers on unlayerd organization
170
pyramidial cell
type of large nerve cell with roughly pyramid shaped body
| most prominant type of neuron in cerebral cortex
171
aptical dendrite
dendrite that extends from a pyramidal cell --> outermost surface of the cortex
172
basal dendrites
one of several dendrites on a pyramidal cell
| extend horizontally from the cell body
173
cortical columns
one of vertical columns that constitute the basic organization of the neocortex
extend through cortex from white matter --> surface
syaptic interconnections within each are vertical
174
basal ganglia
group of forebrain nuclei found deep within cerebral hemispheres
includes caudate nucleus & globus pallidus & putamen
important in motor control
175
caudate nucleus
one of the basal ganglia
| has long extention or tail
176
substantia nigra
brainstem structure in humans
innervates basal ganglia
in midbrain
important motor center
177
limbic system
group of brain nuclei that innervate each other to form a network
hippocampis, amygdala, fornix
limbic structures near base of brain help govern highly motivated behaviors + regulate hormonal systems of body
178
amygdala
group of nuclei in medial, anterior part of temporal lobe
part of limbic system
emotional regulation, odor perception
179
hippocampus
medial temporal lobe structure
important for learning + memory
part of limbic system
180
fornix
fiber tract
extends from hippocampus to mammiliary body
contributes to learning and memory
part of the limbic system
181
cingulate gyrus
cortical portion of limbic system
found in frontal + parietal midline
implicated in direction of attention
strip of the cortex in each hemisphere
182
olfactory bulb
anterior projection of the brain
| provides receptors for smell through small openings in the skull
183
thalamus
cluster of nuclei that directs all incoming sensory info to appropriate regions of cortex
184
hypothalamus
part of the diencephalon (fore post)
lies under thalamus
packed with discrete nuclei
hinger, thirst, temperatur regulation, sex
brain's main interface with normla body systems
controls pituary gland
185
superior colliculi
visual
paired gray matter structures of the dorsal midbrain
recieve visual info & are involved in direction of visual gaze + attention to intended stimuli
186
inferior colliculi
sounds
paired gray matter structures of dorsal midbrain
recieve auditory info
187
tectum
dorsal portion of midbrain
| includes inferior + superior colliculi
188
2 important motor centers in the midbrain
red nucleus
| substantia nigra
189
red nucleus
brainstem structure
related to motor control
important motor center in midbrain
communicates with motoneurons in spinal cord
190
reticular formation
extensive region of brainstem
| involved in arousal/ walking stretches from midbrain --> medulla
191
surface of cerebellum
very convuluted to give it more surface area
| arrangement of cells inside consists of 3 layers
192
purkinje cells
type of large nerve cell in cerebellar cortex
| makes up middle layer of cells inside cerebellum
193
granule cell
"grain"
type of small nerve cell
lies below purkinje cell layer of cerebellum
194
parallel fiber
one of the axons of granulle cells that form outermost layer of cerebral cortex
195
info from ear first enters brain
in the pons
196
meninges
3 protective sheets of tissue that surround the brain & spinal cord
dura matter, pia matter, arachnoid
197
dura matter
outermost of 3 meninges that surround the brain & spinal cord
tough outer sheet
198
pia matter
innermost of 3 meninges that surround the brain & spinal cord
delicate and adheres tightly to surface of brain
199
arachnoid
thin covering of the brain that lies between the dura and pia matter
one of the 3 meninges that surround the brain & spinal cord
webby substance
suspends brain in cerebrospinal fluid
200
cerebrospinal fluid
fluid that fills the cerebral ventricals
| arachnoid suspends brain in this fluid
201
meningitis
small inflammation of the meninges caused by viral of bacterial infection
-headache, fever, stiff neck
202
ventricular system
system of fluid filled cavities inside of the brain
| filled w cerebrospinal fluid
203
functions of cerebrospinal fluid in ventricular system
acts mechanically as shock absorber for brain
| provides medium for th exchange of materials between blood vesssels and brain tissue
204
lateral ventricle
lateral portion of ventricular system within each hemisphere of the brain
extends into all 4 lobes of each hemisphere
205
choroid plexus
vascular portion of the lining of the ventricles
| secretes cerebrospinal fluid by filtering blood
206
third ventricle
midline ventricle that conducts cerebrospinal fluid from lateral ventricle --> fourth ventricle
207
fourth ventricle
passageway within the pons
recieves cerebrospinal fluid from third ventricle & releases it to surround brain + spinal cord
fluid absorbed back into circulatory system later through large veins beneath top of skull
208
carteroid arteries
major arteries that ascend the left & right sides of neck to the brain
supplies blood to anterior and middle cerebral arteries
209
middle cerebral arteries
2 large arteries
provide blood to most of the lateral surfaces of the cerebral hemispheres
arises from carotids
210
anterior cerebral arteries
2 large arteries
provide blood to anterior poles & medial surfaces of the cerebral hemispheres
arises from carotids
211
posterior cerebral arteries
2 large arteries
provide blood to posterior aspects of the cerebral hemispheres, cerebellum, brainstem
arises from basilar artery
provides blood supply for other 1/3 of cortex
212
basilar artery
artery formed by the fusion of the vertebral arteries
supples blood to the brainstem & posterior cerebral arteries
has brainches supplying blood to hindbrain
213
circle of willis
structure at base of brain
| formed by joining of carotid + basilar arteries
214
stroke
damage to region of brain tissue that results from blockage or rupture to vessels that supply blood to that region
215
blood-brain barrier
mechanims that make movement of substances from blood vessels to brain more difficult
affords brain greater protection from exposure to some substances found in blood
216
angiography
brain imaging technique
specialized x-ray image of head is taken after cerebral blood vessels have been filled w radiopaque die
Helps find strokes
aids in diagnosis of vascular disease
217
computerized axial tomography (CT)
noninvasive technique for examining brain structure in humans
uses computer analysis of x-ray absorption at several positions around head
Generates anatomical map of brain based on tissue density
Find tumor that's forming
218
magnetic resonance imaging (MRI)
```
noninvasive technique
uses magnetic energy to generate images
structural details in living brain
higher resolution images than ct
Measure tissue density (how much water is present)
no radioactive, no damaging x-ray
```
219
position emission tomatography (PET)
technique for examining brain function
injections of radioactive substances used by brain into bloodstream & their destination is mapped
images of brain activity, not structure
which brain structures contribute to certain functions
220
functional MRI (fMRI)
magnetic resonance imaging that detects change in blood flow
identifies regions of brain that're particularly active during given task
(extra active places get extra rush of blood)
detects small changes in brain metabolism
generate computer images that reflect activity of diff parts of brain
great pic, slow
221
diffusion tensor imaging (DTI)
modified form of MRI imaging
diffusion of water in confined space used to produce images of axonal fiber tracts
noninvasive
map axonal connections between diff regions of living human brain
determine orientation of fiber tracts
(lion image)
222
transcranial magnetic stimulation (TMS)
stimulation of cortical neurons through application of strong magnetic fields
stimulates cortex of alert, normal subjects
interfere w discrete areas of cortex through electromagnetic induction
repetitive TMS; produces mesurable changes in behavior
223
magnetoencelphalography (MEG)
passive + noninvasve
brain imaging technique
measures tiny magnetic fields produced by active neurons
identifies regions of brain particularly active during given task
responds quickly to moment to moment changes in brain activity
study rapidly shifting patterns of brian activity in cortical circuts
fast, low detail image
224
transcranial direct current stimulation (tDCS)
sends current directly into brain
| hooking 9 volt battery to brain
225
EEG
measure of current itself
| fast, low detail images
226
dydadic functional MRI
fMRI technique
| brains of 2 interacting individuals are simultaneously imaged
227
neurophysiology
study of life processes of neurons that use electrical + chemical signals
228
where are living cells more negative
on the inside
229
ion
atom or molecule that's acquired an electrical charge by gaining/losing electrons
neuron contains them
230
anion
negatively charged ion
what most ions are
ex: protein or chloride ion
231
ca+ion
positively charged ion
| ex: potassium or soduim ion
232
intracellular fluid
watery solution found within cells
what ions are dissolved in
aka cytoplasm
233
extracellular fluid
fluid in spaces between cells and in vascular system
234
cell membrane
lipid bilayer that ensheaths a cell
| seperates intracellular from extracellular fluid
235
resting membrane potental
difference in electrical potential across the membrane of a never cell during inactive period
provides baseline level of polarization found in all cells
236
lipid bilayer
structure of cell membrane
| consists of 2 layers of lipid(fatty) molecules that contain specialized proteins/ receptors
237
large (vs small) neurons
have more complex inputs & outputs
cover greater distances
convey information more rapidly
238
ion channel
pore in cell membrane
permits passage of certain ions trough membrane when the channels are open
proteins that span the membrane
239
gated ion channel
open and close in response to voltage changes, chemicals, or mechanical action
240
selective permeability
property of a membrane that allows some, not other substanes to pass through
241
2 forces that drive ion movement (esp K+ ions)
diffusion
| electrostatic pressure
242
diffusion
spontaneous spread of molecules until a uniform concentration is achieved
molecules diffuse from regions of high --> low concentration
crowded people in a room move to a more empty room
243
concentration gradient
variation of concentration of substance within a region
| high to low
244
electrostatic pressure
natural tendency for charged ions/molecules to move toward areas of opposite charge
cations --> negatively charged interior of cell
anions --> extracellular fluid
BASED ON CHARGE
245
sodium potassium pump
3 Na+ out for every 2 K+ ions in
energetically expensive mechanism
pushes sodium ions out of cell & potassium ions in
maintains resting potential
246
equilibrium
same # in, same # out
point which movement of ions across cell membrane is balanced
electrostatic pressure pulling ions is offset by diffusion force pushing them in opp direction
peak of action potential
247
K+ ion movement
K+ ions wanna come in (electrostatic pressure)
| then diffusion drives them out because too many K+ inside
248
Nernst equation
equation predicting voltage needed to just counterbalance the diffusion force pushing ions across membrane
takes into account diffusion + electrostatic pressure
249
action potential
"rapid electrical signal that travels along axon of neuron"
electrical message of a neuron
that travels along the axon to the presynaptic terminals
brief but large change in neural polarization
info neuron sends to postsynaptic targets is encoded in patterns of action potentials
rapid reversal of membrane potential that momentarily makes inside of membrane positive
actively regenerated down the axon
250
hyperpolarization
an increase in membrane potential
interior of the neuron becomes even more negative (relative to the outside)
further from 0
more negative inside
251
depolarization
reduction in membrane potential
interior of neuron becomes less negative & more like the outside
closer to 0
less negative inside
252
graded response
neuron's change in potential
| since the greater the stimulus the greater the response
253
what happens to potentials produced by stimulation of membrane
diminish as they spread away from point of stimulation
254
local potential
electrical potential
initialed by stimulation at a specific site which is a graded response that spreads passively across cell membrane
decreases in strength with time and distance
255
threshold
stimulus intensity that is just enough to trigger an action potential
256
all or none property
if don't reach threshold, doesn't occur
fact that amplitude of action potential is independant of the magnitude of the stimulus
either fires at full amplitude or doesn't fire at all
257
what causes action potentials to increase in frequency
increased stimulus strength
258
larger depolarizations...
produce more action potentials (not larger ones )
259
afterpotentials/overshoot
positive or negative change in membrane potential that may follow an action potential
related to movement of ions in and out of cell
260
how is action potential created
moveent of sodium ions into cell through channels in the membrane
261
voltae gated Na+ channel
Na+ selective chnnel
opens or closes in response to changes in the voltage of the local membrane potential
mediates the action potential
channel's shape changes when cell membrane becomes depolarized to threshold levels
262
refractory
unresponsive/ inactivated/ unresponsive
263
2 phases of r efractoriness
1 absolute refractory phase
| 2 relative refractory phase
264
absolute refractory phase
brief period of complete insensitivity to stimuli
period immediately following the production of an action potential
because voltage gated Na+ channels are either still open or unresponsive
265
relative refractory phase
period of reduced sensitivity
during which only strong stimulation produces an action potential
follows the absolute refractory phase
because K+ ions are still flowing out so cell is temporarily hyperpolarized after firing action potential
overshoot is a part of this period
266
what does the overall length of the refractory phase do
what determines neuron's maximal rate of firing
267
axon hillock
cone shaped area
from which axon originates out of the cell body
integration zone of neuron
where action potential starts
268
in what direction does axon conduct action potentials
in one direction
| from axon hillock --> axon terminals
269
conduction velocity
speed which an action potential is propagated along length of an axon
270
saltatory conduction
form of conduction characteristic of myelinated axons
action potential jumps from one node of ranvier to the next
speeds up rate of conduction
271
importance of refractory period
if ion channels could open again, action potential wwouldn't go in one direction along the axon
keeps action potential in same direction and not back up towards cell
272
electrical synapse/gap junction
region between neurons
where postsynaptic & presynaptic membranes are so close that action potenntial can jump to postsynaptic membrane WITHOUT BEING TRANSLATED INTO CHEMICAL MESSAGE
faster than synapses
273
postsynaptic potential
local potential initiated by stimulation at a synapse
bref changes occuring after neurotransmitters are released into synapses
determine whether neuron will reach threshold + generate action potential of its own
274
excitatory postsynaptic potential (EPSP)
depolarizing potential in the postsynaptic neuron that's caused by excitatory connections
increases probablility that the postsynaptic neuron will fire an action potential
pushes postsynaptic cell closer to threshold for an action potential
275
inhibitory postsynaptic potential (IPSP)
hyperpolarizing potential in the postsynaptic neuron that's caused by inhibitory connections
decreases probability that the postsynaptic neuron will fire an action potential
results from opening ion channels that permit chloride ions to enter cell
276
temporal summation
summation of postsynaptic potentials that reach axon hillock at different times
closer in time the potntials occur, the more complete the summation
"time difference"
277
can induce postsynaptic potentials
vast number of synaptic inputs arrayed across dendrites + cell body
278
firing of cell (action potential) is influenced by
how close you are to threshold
timing
strength/intensity of postsynaptic potential
where it happens in comparison to where info is integrated
timing in relation to when specific cell is fired
279
exocytosis
process by which
synaptic vesicle fuses with presynaptic terminal membrane to
release neurotransmitter into synaptic cleft
action potential causes exocytosis of several hundred vesicles at a time
280
ligand
substance that binds to receptor molecules
can either activate or block receptor protein
endogenous & exogenous ligands
