Final Exam Flashcards
functional magnetic resonance imaging (fMRI)
A brain-imaging technique that uses MRI to measure changes in blood flow/blood oxygenation associated with brain activity. Good spatial resolution, poor temporal resolution.
electroencephalography (EEG)
A noninvasive technology for recording the electrical fields on the scalp using external electrodes. High temporal resolution, poor spatial resolution
positron emission tomography (PET)
A research technique that detects radioactively-labeled substances (like water or glucose). Good spatial resolution, poor temporal resolution
transcranial magnetic stimulation (TMS)
A safe way to create reversible, “virtual” lesions. Uses a coil with an electric current to create a rapidly-changing magnetic field, which allows us to modify brain activity where the coil is
neuron
A cell in the nervous system specialized for quickly transmitting electrical signals to other neurons. We have ~85 billion
glia/glial cells
Non-neuron nervous system cells that perform a range of supporting functions. At least as many, probably many more, glia than neurons
synapse
The space between pre- and post-synaptic cells
neurotransmitter
a chemical substance that is released at the end of a neuron by the arrival of an action potential and, by diffusing across the synapse, causes the transfer of the action potential to another neuron, a muscle fiber, or some other structure.
receptor
Specialized proteins in the membrane of a postsynaptic cell which neurotransmitters bind to
myelin
A fatty substance on axons which allow electrical signals to reach the ends of neurons faster. Its presence is what creates the appearance of “white matter”
pons
Part of the brain stem. Relays signals between cerebellum and the cerebrum; involved in sleep/wake
midbrain
The middle of three zones in the developing nervous system, becomes midbrain in the brain. Responsible for defensive and reproductive behaviors; visual and auditory reflexes, and is a neurotransmitter source
basal ganglia
A set of closely interconnected gray matter nuclei. Form loops with areas in the frontal cortex. Important in movement, eye movement, thinking, and reward
amygdala
Structure of the limbic system. Involved in rapid evaluation of sensory input; emotional responses to external stimuli (especially fear)
hippocampus
Structure of the limbic system; primary roles are spatial navigation and episodic memory
thalamus
Part of the diencephalon of the forebrain. Relays sensory information to the cortex.
hypothalamus
Part of the diencephalon of the forebrain. Motivates critical drives (fighting, fleeing, feeding, fucking)
cerebellum
Means “little brain,” involved in coordinated movements, balance, associative learning. Has more neurons than the rest of our brain
corpus callosum
Myelinated axons that connect the two hemispheres of the brain; primary purpose is to convey information between hemispheres
cerebrospinal fluid
A fluid which circulates through the ventricles and over the surface of the brain and spinal cord; helps protect the brain and maintain a stable chemical environment for neurons
central nervous system (CNS)
The brain and spinal cord
peripheral nervous system (PNS)
Connects the central nervous system to the rest of the body
somatic nervous system
Controls voluntary movements of skeletal muscles and skin
autonomic nervous system
Controls self-regulated action of internal organs and glands. Divided into sympathetic NS and parasympathetic NS
sympathetic nervous system
“Fight-or-flight” response system; inhibits digestion, speeds up heart rate, increases blood pressure
parasympathetic nervous system
“Rest-and-digest” response system; promotes digestion, slows heart rate, muscles relax
axon
A long, slender extension from the soma of a neuron that conducts signals rapidly across long distances, away from the neuron
soma
The cell body of a neuron
dendrite
Long, branching extensions from the cell body of a neuron that receive signals from other neurons
axon terminal
Branches at the end of the axon, from which neurotransmitters are released
synaptic vesicles
Packages inside the presynaptic neuron which hold neurotransmitters before binding with the membrane and releasing them into the synaptic cleft
resting potential
the electrical potential of a neuron relative to its surroundings when not stimulated or involved in passage of an impulse. About -70 mV
concentration gradient
The difference in concentration between ions outside vs inside the cell. Ions move down the gradient from areas of higher concentration to lower concentration.
electrical gradient
The difference in electrical charge between the inside and outside of the cell. Ions will move down the gradient to areas with their opposite charge.
threshold
The membrane potential that must be reached for a neuron to generate an action potential; usually at -55 mV
action potential
A rapid change/reversal in a neuron’s membrane potential that is used to transmit information from the cell body to the presynaptic terminal
excitatory postsynaptic potential (EPSP)
When the inside of the cell becomes more positive by positive ions flowing into the cell
inhibitory postsynaptic potential (IPSP)
When the inside of the cell becomes more negative, either by bringing in more anions or allowing cations to leave
depolarization
A state in which the electrical charge across the cell membrane is reduced, during the course of an action potential or during communication across a synapse
hyperpolarization
A change in a cell’s membrane potential that makes it more negative. It is the opposite of a depolarization. It inhibits action potentials. Happens after an action potential
voltage-gated channels
Ion channels that allow only certain ions to pass through the membrane. Open when the membrane potential reaches a certain value.
synaptic transmission
When the action potential reaches the end of the axon, Ca2+, which is highly concentrated outside the cell and wants to flow in, comes in through now-open voltage-gated channels. The calcium interacts with vesicles holding NTs, making them sticky and bind to the axon terminal’s wall, where they empty the NTs into the synaptic cleft.
ligand-gated channels
Ion channels which open to allow ions such as Na+, K+, Ca2+, and/or Cl− to pass through the membrane in response to the binding of a chemical messenger (i.e. a ligand), such as a neurotransmitter
degradation
A mechanism for removing neurotransmitters from the synaptic cleft: specific enzymes break apart the neurotransmitters
reuptake
A mechanism for removing neurotransmitters from the synaptic cleft: special protein transporters in the membrane will selectively pull NTs back inside the cell presynaptically, postsynaptically, or into neighboring cells
transporters
Special proteins in the membrane of a cell that complete reuptake of neurotransmitters
glutamate
An amino acid neurotransmitter. Most common excitatory NT in the CNS
GABA
An amino acid neurotransmitter. Most common inhibitory NT in the CNS
dopamine
A monoamine neurotransmitter. Involved in reward system, drugs, motor control, cognition, schizophrenia
acetylcholine
The most common excitatory neurotransmitter in the PNS. Causes muscle contractions. This is the neurotransmitter that Loewi discovered.
serotonin
A monoamine neurotransmitter.. Regulates appetite, sleep, and mood
norepinephrine
A monoamine neurotransmitter. Regulates arousal, alertness, attention
agonist
Increases the effects of NTs
antagonist
Decreases the effects of NTs
antagonist
Decreases the effects of NTs
slow wave sleep (SWS)
Stage 3 of sleep, the deepest stage of non-REM. Associated with the basal forebrain. Brain waves are low frequency, high amplitude (synchronized)
REM sleep
Rapid Eye Movement. A stage of sleep in which dreams occur and the body is paralyzed (aside from small facial muscles), but the eyes exhibit rapid movement. Brain waves at high frequencies, low amplitude, resembles waking a little bit.
sleep cycles through the night
We move through the stages of sleep several times a night. We don’t re-enter stage 3 in the second half of the night, and we spend more time in REM in the second half of the night.
sleep cycles through the night
We move through the stages of sleep several times a night. We don’t re-enter stage 3 in the second half of the night, and we spend more time in REM in the second half of the night.
slow wave sleep is associated with the ___ (brain region)
basal forebrain
REM is associated with the ___ (brain region)
pons
circadian rhythm
A natural internal rhythm (of sleep/wake) that runs on an approximately 24-hour cycle
suprachiasmatic nucleus (SCN)
A region in the hypothalamus in which cells maintain their own 24-hour clock, and serve as the master clock for the body’s circadian rhythms
suprachiasmatic nucleus (SCN)
A region in the hypothalamus in which cells maintain their own 24-hour clock, and serve as the master clock for the body’s circadian rhythms
pineal gland
A gland which produces and releases melatonin. Receives signals from the SCN