Neuroscience Exam Questions and
Answers (sixth edition).
Action potential - ANSWER-The electrical signal generated and conducted along axons
(or muscle fibers) by which inforation is conveyed from one place to another in the
nervous system (or within muscle fibers)
afferent neurons - ANSWER-Neurons or axons that conduct action potentials from the
periphery toward the central nervous system.
anterograde - ANSWER-Signals or impulses that travel "forward", e.g., from the cell
body to the axon terminal, from the presynaptic terminal to the postsynaptic cell, or from
the CNS to the periphery
associational systems - ANSWER-Neural cell circuits that are not part of the relatively
defined sensory (input) and motor (output) systems; they mediate the most complex and
least well-defined brain functions that require the integration or association of signals
from multiple sensory and/or mortor systems.
astrocytes - ANSWER-One of the three major classes of glial cells found in the central
nervous sytem; important in maintaing and regulating, in a variety of ways, an
appropriate chemical environment for neuronal signaling; also involved in the formation
of the blood-brain barrier, the secretion of substances that influence the construction of
new synaptic connections, and the proliferation of new cells in the adult brain that retain
characteristics of stem cells.
autonomic ganglia - ANSWER-Collections of autonomic motor neurons outside the
central nervous system that innervate visceral smooth muscles, cardiac muscle, and
glands
axon - ANSWER-The neuronal process (typically, much longer than any dendrite) that
conveys the action potential from the nerve cell body to its terminals.
bacteriorhodopsin - ANSWER-A protein that, in response to light of the proper
wavelength, acts as a proton pump transporting protons from inside the cell to outside;
in its native host, the resulting proton gradient is subsequently converted into chemical
energy; when engineered into a neuron for optogenetics, it hyperpolarizes the neruon
when exposed to light.
blood oxygenation level-dependent (BOLD) - ANSWER-Endogenous signals reflecting
the oxygenation of hemoglobin in blood that are modulated by changes in the local level
of neural activity; for example, when neural activity in a local brain region increases,
more oxygen is consumed and within seconds the local microvasculature responds by
,increasing the flow of oxygen-rich blood to the active region, thus constituting a BOLD
signal that may be detected by fMRI.
brain - ANSWER-The rostral (supraspinal) portion of the central nervous system
comprised of the cerebral hemispheres, diencephalon, cerebellum, and brainstem.
calcium imaging - ANSWER-Method of monitoring by optical means the levels of
calcium within cells using calcium-sensitive fluorescent dyes; calcium dynamics within
the cytoplasm of neurons reflect the integration of synaptic inputs and the generation of
postsynaptic electrical activity.
central nervous sytem (CNS) - ANSWER-The brain and spinal cord of vertebrates (by
analogy, the central nerve cord and ganglia of invertebrates).
cerebral angiography - ANSWER-An x-ray based means for imaging blood vessels in
the brain involving injection of a contrast agent into the systemic circulation.
channelrhodopsin - ANSWER-Typically, a protein that, in response to light of the proper
wavelength, opens a channel that is permeable to cations; when engineered into a
neuron for optogenetics, it depolarizes the neuron when exposed to light; anion-
conducting channelrhodopsins have also been discovered, which would have inhibitory
effects when activated in mature neurons.
chemical synapses - ANSWER-Synapses that transmit information via the secretion of
chemical signals (neurotransmitters).
cognitive neuroscience - ANSWER-The field of neuroscience devoted to studying and
understanding cognitive functions.
columns - ANSWER-Term used to describe an elongated gray matter structure (e.g.,
the motor neuronal pool in the ventral horn of the spinal cord that innervates a muscle)
or a subdivision of white matter (e.g., a region of white matter in the spinal cord
containing long axon tracts).
commissures - ANSWER-Axon tracts that cross the midline of the brain or spinal cord.
computational map - ANSWER-An assembly of neural circuits in a specific brain region
that represent inputs that do not have a direct correspondence to a topographic map
such as those in the somatosensory or visual systems. Some cognitive capacities,
including language and declarative memory, are thought to depend on computational
maps.
computerized tomography (CT) - ANSWER-Radiographic procedure in which a three-
dimensional image of a body strucutre in constructed by computer from a series of
cross-sectional X-ray images.
,conditional mutations - ANSWER-"A genetic engineering approach, typically reliant
upon the Cre/lox system, whereby an exogenous recombinase enzyme recognizes
unique DNA excision sequences (loxP sequences) introduced at the 5' and 3' ends of
an endogenous gene and eliminates the intervening sequence."
convergence - ANSWER-Innervation of a target cell by axons from more than one
neuron. In vision refers specifically to the convergence of both rod and cone
photoreceptor cels onto retinal ganglion cells.
cortex (pl. cortices) - ANSWER-The superficial mantle of gray matter (a sheet-like array
of nerve cells) covering the cerebral hemispheres and cerebellum, where most of the
neurons in the brain are located.
cranial nerve ganglia - ANSWER-The sensory ganglia associated with the cranial
nerves; these correspond to the dorsal root ganglia of the segmental nerves of the
spinal cord.
Cre recombinase - ANSWER-A viral DNA cutting enzyme used to excise a floxed
exons. (Cre stands for Causes recombination)
Cre/lox - ANSWER-A genetic engineering system for achieving conditional mutations of
endogenous mammalian genes using in- troduced loxP sequences, which are not found
in mammalian genomes but occur in bacterial genomes and are targeted by certain
viruses, and a viral DNA cutting enzyme, Cre recom- binase. With expression of the Cre
DNA introduced into host genome, the resulting Cre recombinase engages the loxP
binding sites, and the intervening endogenous exon targeted for elimination (the so-
called floxed sequence) is excised.
dendrites - ANSWER-Neuronal processes (typically, much shorter tha the axon) arising
from the nerve cell body that receive synaptic input.
diffusion tensor imaging (DTI) - ANSWER-A type of magnetic resonance imaging used
in live humans that allows for the selective visualization of large axon tracts in the brain
based upon the alignment of the water molecules in myelinated axons bundled together
and extending in the same direction.
divergence - ANSWER-The branching of a single axon to innervate multiple target cells
dorsal root ganglia - ANSWER-The segmental sensory ganglia of the spinal cord; they
contain the cell bodies of the first-order neurons of all somatic sensory and visceral
sensory pathways arising in the spinal cord.
efferent neurons - ANSWER-Neurons or axons that conduct information away from the
central nervous system toward the periphery.
, electrical synapse - ANSWER-Synapses that transmit information va the direct flow of
electrical current at gap junctions.
electroencephalography (EEG) - ANSWER-The study of electrical potentials generated
in the brain recorded from electrodes placed on the scalp.
electrophysiological recording - ANSWER-Measure of the electrical activity across the
membrane of a nerve cell by use of electrodes.
enteric nevous system (ENS) - ANSWER-A subsystem of the visceral motor system,
made up of small ganglia and individual neurons scattered throughout the wall of the
gut; influences gastric motility and secretion. Also called the enteric system.
event related potential (ERP) - ANSWER-Averaged EEG recordings measuring time-
locked brain responses to repeated presentations of a stimulus or repeated execution of
a motor task.
extracellular recording - ANSWER-Recording the electrical potentials in the extracellular
space near active neurons. Compare the intracellular recording.
functional magnetic resonance imaging (fMRI) - ANSWER-Magnetic resonance imaging
that detects changes in blood flow and therefore identifies regions of the brain that are
particularly active during a given task.
ganglia (sing. ganglion) - ANSWER-Collection of hundreds to thousands of neurons
found outside the brain and spinal cord along the course of peripheral nerves.
gap junctions - ANSWER-Specialized intercellualar contacts formed by channels that
directly connect the cytoplasm of two cells.
gene - ANSWER-Hereditary unit located on the chromosomes; genetic information is
carried by linear sequences of nucleotides in DNA that code for corresponding
sequences of amino acids.
genetic analysis - ANSWER-The analysis of the relationship between single genes and
the phenotypes to which each gene contributes.
genetic engineering - ANSWER-A methodological means for inducing mutations in
genes or otherwise editing or altering the struc- ture and/or the function of targeted
genes for experimental or therapeutic benefit. Also called reverse genetics.
genome-wide association studies (GWAS) - ANSWER-A statistical correlation of likely
associated genes drawn from analyses of large cohorts of individuals with the same
phenotype or clinical diagnoses.
Answers (sixth edition).
Action potential - ANSWER-The electrical signal generated and conducted along axons
(or muscle fibers) by which inforation is conveyed from one place to another in the
nervous system (or within muscle fibers)
afferent neurons - ANSWER-Neurons or axons that conduct action potentials from the
periphery toward the central nervous system.
anterograde - ANSWER-Signals or impulses that travel "forward", e.g., from the cell
body to the axon terminal, from the presynaptic terminal to the postsynaptic cell, or from
the CNS to the periphery
associational systems - ANSWER-Neural cell circuits that are not part of the relatively
defined sensory (input) and motor (output) systems; they mediate the most complex and
least well-defined brain functions that require the integration or association of signals
from multiple sensory and/or mortor systems.
astrocytes - ANSWER-One of the three major classes of glial cells found in the central
nervous sytem; important in maintaing and regulating, in a variety of ways, an
appropriate chemical environment for neuronal signaling; also involved in the formation
of the blood-brain barrier, the secretion of substances that influence the construction of
new synaptic connections, and the proliferation of new cells in the adult brain that retain
characteristics of stem cells.
autonomic ganglia - ANSWER-Collections of autonomic motor neurons outside the
central nervous system that innervate visceral smooth muscles, cardiac muscle, and
glands
axon - ANSWER-The neuronal process (typically, much longer than any dendrite) that
conveys the action potential from the nerve cell body to its terminals.
bacteriorhodopsin - ANSWER-A protein that, in response to light of the proper
wavelength, acts as a proton pump transporting protons from inside the cell to outside;
in its native host, the resulting proton gradient is subsequently converted into chemical
energy; when engineered into a neuron for optogenetics, it hyperpolarizes the neruon
when exposed to light.
blood oxygenation level-dependent (BOLD) - ANSWER-Endogenous signals reflecting
the oxygenation of hemoglobin in blood that are modulated by changes in the local level
of neural activity; for example, when neural activity in a local brain region increases,
more oxygen is consumed and within seconds the local microvasculature responds by
,increasing the flow of oxygen-rich blood to the active region, thus constituting a BOLD
signal that may be detected by fMRI.
brain - ANSWER-The rostral (supraspinal) portion of the central nervous system
comprised of the cerebral hemispheres, diencephalon, cerebellum, and brainstem.
calcium imaging - ANSWER-Method of monitoring by optical means the levels of
calcium within cells using calcium-sensitive fluorescent dyes; calcium dynamics within
the cytoplasm of neurons reflect the integration of synaptic inputs and the generation of
postsynaptic electrical activity.
central nervous sytem (CNS) - ANSWER-The brain and spinal cord of vertebrates (by
analogy, the central nerve cord and ganglia of invertebrates).
cerebral angiography - ANSWER-An x-ray based means for imaging blood vessels in
the brain involving injection of a contrast agent into the systemic circulation.
channelrhodopsin - ANSWER-Typically, a protein that, in response to light of the proper
wavelength, opens a channel that is permeable to cations; when engineered into a
neuron for optogenetics, it depolarizes the neuron when exposed to light; anion-
conducting channelrhodopsins have also been discovered, which would have inhibitory
effects when activated in mature neurons.
chemical synapses - ANSWER-Synapses that transmit information via the secretion of
chemical signals (neurotransmitters).
cognitive neuroscience - ANSWER-The field of neuroscience devoted to studying and
understanding cognitive functions.
columns - ANSWER-Term used to describe an elongated gray matter structure (e.g.,
the motor neuronal pool in the ventral horn of the spinal cord that innervates a muscle)
or a subdivision of white matter (e.g., a region of white matter in the spinal cord
containing long axon tracts).
commissures - ANSWER-Axon tracts that cross the midline of the brain or spinal cord.
computational map - ANSWER-An assembly of neural circuits in a specific brain region
that represent inputs that do not have a direct correspondence to a topographic map
such as those in the somatosensory or visual systems. Some cognitive capacities,
including language and declarative memory, are thought to depend on computational
maps.
computerized tomography (CT) - ANSWER-Radiographic procedure in which a three-
dimensional image of a body strucutre in constructed by computer from a series of
cross-sectional X-ray images.
,conditional mutations - ANSWER-"A genetic engineering approach, typically reliant
upon the Cre/lox system, whereby an exogenous recombinase enzyme recognizes
unique DNA excision sequences (loxP sequences) introduced at the 5' and 3' ends of
an endogenous gene and eliminates the intervening sequence."
convergence - ANSWER-Innervation of a target cell by axons from more than one
neuron. In vision refers specifically to the convergence of both rod and cone
photoreceptor cels onto retinal ganglion cells.
cortex (pl. cortices) - ANSWER-The superficial mantle of gray matter (a sheet-like array
of nerve cells) covering the cerebral hemispheres and cerebellum, where most of the
neurons in the brain are located.
cranial nerve ganglia - ANSWER-The sensory ganglia associated with the cranial
nerves; these correspond to the dorsal root ganglia of the segmental nerves of the
spinal cord.
Cre recombinase - ANSWER-A viral DNA cutting enzyme used to excise a floxed
exons. (Cre stands for Causes recombination)
Cre/lox - ANSWER-A genetic engineering system for achieving conditional mutations of
endogenous mammalian genes using in- troduced loxP sequences, which are not found
in mammalian genomes but occur in bacterial genomes and are targeted by certain
viruses, and a viral DNA cutting enzyme, Cre recom- binase. With expression of the Cre
DNA introduced into host genome, the resulting Cre recombinase engages the loxP
binding sites, and the intervening endogenous exon targeted for elimination (the so-
called floxed sequence) is excised.
dendrites - ANSWER-Neuronal processes (typically, much shorter tha the axon) arising
from the nerve cell body that receive synaptic input.
diffusion tensor imaging (DTI) - ANSWER-A type of magnetic resonance imaging used
in live humans that allows for the selective visualization of large axon tracts in the brain
based upon the alignment of the water molecules in myelinated axons bundled together
and extending in the same direction.
divergence - ANSWER-The branching of a single axon to innervate multiple target cells
dorsal root ganglia - ANSWER-The segmental sensory ganglia of the spinal cord; they
contain the cell bodies of the first-order neurons of all somatic sensory and visceral
sensory pathways arising in the spinal cord.
efferent neurons - ANSWER-Neurons or axons that conduct information away from the
central nervous system toward the periphery.
, electrical synapse - ANSWER-Synapses that transmit information va the direct flow of
electrical current at gap junctions.
electroencephalography (EEG) - ANSWER-The study of electrical potentials generated
in the brain recorded from electrodes placed on the scalp.
electrophysiological recording - ANSWER-Measure of the electrical activity across the
membrane of a nerve cell by use of electrodes.
enteric nevous system (ENS) - ANSWER-A subsystem of the visceral motor system,
made up of small ganglia and individual neurons scattered throughout the wall of the
gut; influences gastric motility and secretion. Also called the enteric system.
event related potential (ERP) - ANSWER-Averaged EEG recordings measuring time-
locked brain responses to repeated presentations of a stimulus or repeated execution of
a motor task.
extracellular recording - ANSWER-Recording the electrical potentials in the extracellular
space near active neurons. Compare the intracellular recording.
functional magnetic resonance imaging (fMRI) - ANSWER-Magnetic resonance imaging
that detects changes in blood flow and therefore identifies regions of the brain that are
particularly active during a given task.
ganglia (sing. ganglion) - ANSWER-Collection of hundreds to thousands of neurons
found outside the brain and spinal cord along the course of peripheral nerves.
gap junctions - ANSWER-Specialized intercellualar contacts formed by channels that
directly connect the cytoplasm of two cells.
gene - ANSWER-Hereditary unit located on the chromosomes; genetic information is
carried by linear sequences of nucleotides in DNA that code for corresponding
sequences of amino acids.
genetic analysis - ANSWER-The analysis of the relationship between single genes and
the phenotypes to which each gene contributes.
genetic engineering - ANSWER-A methodological means for inducing mutations in
genes or otherwise editing or altering the struc- ture and/or the function of targeted
genes for experimental or therapeutic benefit. Also called reverse genetics.
genome-wide association studies (GWAS) - ANSWER-A statistical correlation of likely
associated genes drawn from analyses of large cohorts of individuals with the same
phenotype or clinical diagnoses.
