Midterm 1 Flashcards
cognitive neuroscience
The study of how the brain processes information, builds memories, navigates decisions, etc.
emergent properties
Characteristics of a system that do not belong to any individual component
connectional methods
Methods we use to understand connections between regions of the brain. Examples include tracking tracers throughout the NS, and diffusion tensor imaging
diffusion tensor imaging (DTI)
A connectional method where magnetic resonance is used to trace water as it diffuses throughout the brain along tracts of neurons, giving us maps of the tracts
correlational methods
Methods that involve making observations of brain activity while an individual performs some type of behavior.
microelectrodes
Small electrodes surgically implanted into the brain that allow researchers to measure the electrical activity of neurons or to stimulate target brain regions
microdialysis
A technique for sampling the chemical properties of the extracellular fluid surrounding neurons via a tiny probe in the brain
electroencephalography (EEG)
A noninvasive technology for recording the electrical fields on the scalp using external electrodes. High temporal resolution, poor spatial resolution
magnetoencephalography (MEG)
A noninvasive technique to monitor electrical activity in the brain by placing sensitive magnetic detectors on the scalp, good for use with small kids
positron emission tomography (PET)
A research technique that detects radioactively-labeled substances (like water or glucose). Good spatial resolution, poor temporal resolution
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.
lesion methods
One of the oldest approaches to causal inference in mapping out brain behavior; involves studying the effects of lesions (damaged areas) in the brain. Study patients with traumatic brain injuries.
stimulation methods
A method which involves actively stimulating a brain region or neural circuit and then observing the effects on cognition and behavior
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 activitu where the coil is
anchoring bias
Human tendency to become overly influenced by a single observation, usually the first one (“the anchor”), so it drowns out or distorts subsequent info to make it more consistent with the anchor
confirmation bias
Human tendency to seek out or emphasize information that fits with our own beliefs, and ignoring information that conflicts with them
scientific method
observe, make a hypothesis, make predictions, test
central nervous system
The brain and spinal cord
optogenetics
A new technique to manipulate the activity of specific subsets of neurons. Insert genes, fibre-optic light to stimulate brain activity
peripheral nervous system
Connects the central nervous system to the rest of the body
forebrain
The anterior of three zones in the developing nervous system. Composed of the telencephalon and diencephalon
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
hindbrain
The posterior of three zones in the developing nervous system; composed of the medulla, pons, and cerebellum
telencephalon
Composed of cerebral cortex, basal ganglia, and limbic system
diencephalon
Composed of the thalamus and hypothalamus
rostral
towards the front
caudal
towards the back
dorsal
towards the top
ventral
towards the bottom
anterior
towards the front
posterior
towards the back
superior
towards the top
inferior
towards the bottom
medial
towards the middle
lateral
towards the side
ipsilateral
on the same side
contralateral
on the opposite side
sensory neurons
Have receptors in the skin, muscles, and joints; convey sensory input
motor neurons
Extend to the muscles, stimulate muscles to contract
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
brainstem
Most posterior region of the brain, communicates between spinal cord and anterior structures of the NS. Composed of medulla, pons, and midbrain.
medulla
Involved in involuntary functions like breathing and blood flow
pons
Relays signals between cerebellum and the cerebrum; involved in sleep/wake
cerebellum
Means “little brain,” involved in coordinated movements, balance, associative learning. Has more neurons than the rest of our brain
superior colliculum
bump in the midbrain responsible for visual reflexes
inferior colliculum
bump in the midbrain responsible for auditory reflexes
reticular formation
structure in the midbrain that regulates sleep/wake
locus coeruleus
Region in midbrain; releases norepinephrine
substantia nigra
Region in midbrain; releases dopamine
raphae nuclei
Region in midbrain; releases serotonin
hypothalamus
Part of the diencephalon of the forebrain. Motivates critical drives (fighting, fleeing, feeding, fucking)
thalamus
Part of the diencephalon of the forebrain. Relays sensory information to the cortex.
pituitary gland
A major endocrine gland which is below and connected to the hypothalamus
cerebrum
the most superior portion of the central nervous system; includes left and right hemispheres and subcortical structures like thalamus and basal ganglia
cerebral cortex
AKA gray matter; the outermost covering of the brain. Primarily composed of cell bodies and dendrites
gyrus/gyri
What we call the bumps on the cerebral cortex
sulcus/sulci
What we call the grooves in the cerebral cortex
corpus callosum
Myelinated axons that connect the two hemispheres of the brain; primary purpose is to convey information between hemispheres
frontal lobe
The region of cortex at the front of the brain; involved in motor control. Includes primary motor cortex, prefrontal cortex, orbitofrontal cortex.
primary motor cortex
A long strop of areas in the frontal lobe that controls movements of individual body parts
prefrontal cortex
Area in the frontal lobe that assembles elaborate sequences of movement, also important for goal planning and cognition
orbitofrontal cortex
Area in the frontal lobe above the eyes, omportant in setting priorities
parietal lobe
The region of the cortex on top and towards the back of the brain; involved in touch. Contains primary somatosensory cortex
primary somatosensory cortex
Area in the parietal lobe; handles sensory input from skin, muscles, and joints of individual body parts
occipital lobe
Region of the cortex behind the parietal lobe at the back of the brain; involved in vision/ Contains primary visual cortex.
primary visual cortex
Area in the occipital lobe where visual information is first processed
temporal lobe
Bottom-most region of the cortex; involved in hearing. Contains the primary auditory cortex, fusiform gyrus
primary auditory cortex
Area in the temporal lobe which receives and processes auditory information
fusiform gyrus
Area in the temporal lobe which helps a ventral visual pathway in the identification, categorization , and evaluation of visual inputs
insula
A region of cortex hidden inside the lateral sulcus which represents internal sensations of bodily organs and states like pain, hunger, arousal, fatigue
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
dorsal striatum
The outermost structure of the basal ganglia, includes caudate and putamen nuclei
ventral striatum
Region in the ventral part of the basal ganglia, contains the nucleus accumbens; important in reward and addiction
limbic system
A collection of structures surrounding the brain stem, important for motivation and emotion. Primary structures are the amygdala and hippocampus
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
anterior cingulate cortex
The anterior portion of the cingulate gyrus; involved in motor control and decision making
ventricles
four cavities in the brain filled with cerebrospinal fluid
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
neuron
A cell in the nervous system specialized for quickly transmitting electrical signals to other neurons. We have ~85 billion
membrane
Outer covering of a cell which separates it from the outside environment
dendrites
Long, branching extensions from the cell body of a neuron that receive signals from other neurons
soma
The cell body of a neuron
nucleus (of a cell)
Control center in the cell body which regulates cell activity
axon
A long, slender extension from the soma of a neuron that conducts signals rapidly across long distances, away from the neuron
axon terminals
Branches at the end of the axon, from which neurotransmitters are released
afferent
What we call neurons that convey info INTO the nervous system; sensory neurons
efferent
What we call neurons that convey info OUT of the nervous system; motor neurons
multipolar neuron
Neurons with 3 or more extensions coming off the cell body
bipolar neuron
Neurons with just one dendrite and one axon connected to the cell body
monopolar/unipolar neurons
Neurons with a single extension that leaves the cell body (this extension may split in 2 directions)
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
oligodendrocyte
A type of glial cell. Their extensions act as myelin for cells in the central nervous system, wrapping around the axons of neurons
schwann cell
A type of glial cell. Act as segments of myelin for cells in the peripheral nervous system
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”
nodes of Ranvier
An exposed part of an axon without myelin covering it; necessary in helping action potentials reach down the axon quickly
astrocyte
A type of glial cell. Primary role is to nourish neurons by bringing in nutrients from the blood, and removing waste products
microglia
A type of glial cell. Primary role is cleaning around neurons by engulfing and destroying debris.
Loewi
A scientist who discovered that neurons communicate chemically at synapses. He soaked a frog heart in a solution, and then stimulated a nerve to slow its heart rate. He then soaked a different frog heart in the same solution, and its heart rate slowed down too.
synaptic cleft
The space between pre- and post-synaptic cells
synaptic vesicles
Packages inside the presynaptic neuron which hold neurotransmitters before binding with the membrane and releasing them into the synaptic cleft
acetylcholine
The most common excitatory neurotransmitter in the PNS. Causes muscle contractions. This is the neurotransmitter that Loewi discovered.
monoamines
A class of neurotransmitter that includes dopamine, epinephrine, norepinephrine, serotonin, and melatonin
dopamine
A monoamine neurotransmitter. Involved in reward system, drugs, motor control, cognition, schizophrenia
epinephrine
A monoamine neurotransmitter. AKA adrenaline, fight-or-flight
norepinephrine
A monoamine neurotransmitter. Regulates arousal, alertness, attention
serotonin
A monoamine neurotransmitter.. Regulates appetite, sleep, and mood
melatonin
A monoamine neurotransmitter. Involved in sleep and wake
glutamate
An amino acid neurotransmitter. Most common excitatory NT in the CNS
GABA
An amino acid neurotransmitter. Most common inhibitory NT in the CNS
receptors
Specialized proteins in the membrane (of a postsynaptic cell), which neurotransmitters bind to
ionotropic receptors
Receptors that, when activated by a neurotransmitter, open a channel in the cell membrane to allow ions to enter or leave the cell
metabotropic receptors
Receptors that, when activated by a neurotransmitter, cause changes inside the cell by a cascade of signals
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
membrane potential
The difference in electrical charge between the inside and outside of the cell. In a neuron at rest, membrane potential is at -70 millivolts, meaning the inside is more negative than the outside
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
agonists
Molecules that mimic or extend the activity of a neurotransmitter
antagonists
Molecules that decrease the activity of a neurotransmitter
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
temporal summation
The process by which EPSPs or IPSPs that occur at slightly different times will add up at the soma. One presynaptic neuron releases NTs many times over a period of time
spatial summation
The process by which EPSPs and IPSPs that arrive on different branches of the dendrites will converge at the soma. Multiple presynaptic neurons release NTs at the same time
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
threshold
The membrane potential that must be reached for a neuron to generate an action potential; usually at -55 mV
axon hillock
Where the axon connects to the cell body, the location where the action potential is generated
sodium ions
Na+ ions. When the neuron is at rest, there is a lot of Na+ outside the cell, not as much inside.
potassium ions
K+ ions. When the neuron is at rest, there is a lot of K+ inside the cell, not as much outside
voltage-gated ion channels
Ion channels that allow only certain ions to pass through the membrane. Open when the membrane potential reaches a certain value.
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.
refractory period
The time following the action potential where voltage-gated ion channels are inactivated and unable to generate another action potential
saltatory conduction
The propagation of an action potential along an myelinated axon, in which the action potential “jumps” along the axon from one node of Ranvier to the next.
neurotransmitter release
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.
lidocaine mechanisms
Lidocaine blocks voltage-gated Na+ channels, preventing action potentials from spreading along the axon. When lidocaine is administered, electrical signals are blocked at their site of origin, preventing pain sensations from arising.
golgi stains
A stain that allows us to see the shapes and lengths of neurons. Only some cells take up this stain.
nissl stains
A stain that allows us to see the densities of cells in an area. Stains material in the nucleus of the cell; can’t see axons or dendrites
substantia nigra
A group of dark-colored cells in the midbrain that are a major source of dopamine
Parkinson’s disease
A motor disorder caused by the progressive loss of dopamine cells in the substantia nigra
tract
A group of axons in the CNS
nerve
A group of axons in the PNS
nucleus
A group of cell bodies in the CNS
ganglion
A group of cell bodies in the PNS
Henry Molaison
A famous patient whose doctor removed his hippocampus to stop seizures; lost his ability to form new episodic memories
spatial resolution
where the brain is active
temporal resolution
When the brain is active
Causal inference
Does this (in the brain) cause that (behavior)?
