Vocabulary

Ablation: Surgical removal of brain tissue.
Action Potential: A transient all-or-nothing electrical current that is conducted down the axon when the membrane potential reaches the threshold of excitation.
Action potential: A transient all-or-nothing electrical current that is conducted down the axon when the membrane potential reaches the threshold of excitation.
Afferent nerves: Nerves that carry messages to the brain or spinal cord.
Agnosias: Due to damage of Wernicke’s area. An inability to recognize objects, words, or faces.
Aphasia: Due to damage of the Broca’s area. An inability to produce or understand words.
Arcuate fasciculus: A fiber tract that connects Wernicke’s and Broca’s speech areas.
Autonomic nervous system: A part of the peripheral nervous system that connects to glands and smooth muscles. Consists of sympathetic and parasympathetic divisions.
Axial plane: See “horizontal plane.”
Axon: Part of the neuron that extends off the soma, splitting several times to connect with other neurons; main output of the neuron.
Axon: Part of the neuron that extends off the soma, splitting several times to connect with other neurons; main output of the neuron.
Basal ganglia: Subcortical structures of the cerebral hemispheres involved in voluntary movement.
Blood-oxygen-level-dependent (BOLD): The signal typically measured in fMRI that results from changes in the ratio of oxygenated hemoglobin to deoxygenated hemoglobin in the blood.
Brain stem: The “trunk” of the brain comprised of the medulla, pons, midbrain, and diencephalon.
Brain Stem: The “trunk” of the brain comprised of the medulla, pons, midbrain, and diencephalon.
Broca’s Area: An area in the frontal lobe of the left hemisphere. Implicated in language production.
Broca’s area: An area in the frontal lobe of the left hemisphere. Implicated in language production.
Callosotomy: Surgical procedure in which the corpus callosum is severed (used to control severe epilepsy).
Case study: A thorough study of a patient (or a few patients) with naturally occurring lesions.
Cell membrane: A bi-lipid layer of molecules that separates the cell from the surrounding extracellular fluid.
Central Nervous System: The portion of the nervous system that includes the brain and spinal cord.
Central nervous system: The part of the nervous system that consists of the brain and spinal cord.
Central sulcus: The major fissure that divides the frontal and the parietal lobes.
Cerebellum: The distinctive structure at the back of the brain, Latin for “small brain.”
Cerebellum: A nervous system structure behind and below the cerebrum. Controls motor movement coordination, balance, equilibrium, and muscle tone.
Cerebellum: The distinctive structure at the back of the brain, Latin for “small brain.”
Cerebral cortex: The outermost gray matter of the cerebrum; the distinctive convoluti characteristic of the mammalian brain.
Cerebral hemispheres: The cerebral cortex, underlying white matter, and subcortical structures.
Cerebrum: Consists of left and right hemispheres that sit at the top of the nervous system and engages in a variety of higher-order functions.
Cerebrum: Usually refers to the cerebral cortex and associated white matter, but in some texts includes the subcortical structures.
Cerebrum: Usually refers to the cerebral cortex and associated white matter, but in some texts includes the subcortical structures.
Cingulate gyrus: A medial cortical portion of the nervous tissue that is a part of the limbic system.
Computerized axial tomography: A noninvasive brain-scanning procedure that uses X-ray absorption around the head.
Contralateral: Literally “opposite side”; used to refer to the fact that the two hemispheres of the brain process sensory information and motor commands for the opposite side of the body (e.g., the left hemisphere controls the right side of the body).
Contralateral: Literally “opposite side”; used to refer to the fact that the two hemispheres of the brain process sensory information and motor commands for the opposite side of the body (e.g., the left hemisphere controls the right side of the body).
Converging evidence: Similar findings reported from multiple studies using different methods.
Coronal plane: A slice that runs from head to foot; brain slices in this plane are similar to slices of a loaf of bread, with the eyes being the front of the loaf.
Corpus Callosum: The thick bundle of nerve cells that connect the two hemispheres of the brain and allow them to communicate.
Dendrite: Part of a neuron that extends away from the cell body and is the main input to the neuron.
Dendrites: Part of a neuron that extends away from the cell body and is the main input to the neuron.
Deoxygenated hemoglobin: Hemoglobin not carrying oxygen.
Depolarization: A change in a cell’s membrane potential, making the inside of the cell more positive and increasing the chance of an action potential.
Diffuse optical imaging (DOI): A neuroimaging technique that infers brain activity by measuring changes in light as it is passed through the skull and surface of the brain.
Diffuse Optical Imaging (DOI): A neuroimaging technique that infers brain activity by measuring changes in light as it is passed through the skull and surface of the brain.
Diffusion: The force on molecules to move from areas of high concentration to areas of low concentration.
Ectoderm: The outermost layer of a developing fetus.
Efferent nerves: Nerves that carry messages from the brain to glands and organs in the periphery.
Electroencephalography: A technique that is used to measure gross electrical activity of the brain by placing electrodes on the scalp.
Electroencephalography (EEG): A neuroimaging technique that measures electrical brain activity via multiple electrodes on the scalp.
Electroencephalography (EEG): A neuroimaging technique that measures electrical brain activity via multiple electrodes on the scalp.
Electrostatic pressure: The force on two ions with similar charge to repel each other; the force of two ions with opposite charge to attract to one another.
Event-related potentials: A physiological measure of large electrical change in the brain produced by sensory stimulation or motor responses.
Excitatory postsynaptic potentials: A depolarizing postsynaptic current that causes the membrane potential to become more positive and move towards the threshold of excitation.
Forebrain: A part of the nervous system that contains the cerebral hemispheres, thalamus, and hypothalamus.
Fornix: (plural form, fornices) A nerve fiber tract that connects the hippocampus to mammillary bodies.
Frontal Lobe: The front most (anterior) part of the cerebrum; anterior to the central sulcus and responsible for motor output and planning, language, judgment, and decision-making.
Frontal lobe: The front most (anterior) part of the cerebrum; anterior to the central sulcus and responsible for motor output and planning, language, judgment, and decision-making.
Frontal lobe: The most forward region (close to forehead) of the cerebral hemispheres.
Functional magnetic resonance imaging: (or fMRI) A noninvasive brain-imaging technique that registers changes in blood flow in the brain during a given task (also see magnetic resonance imaging).
Functional magnetic resonance imaging (fMRI): Functional magnetic resonance imaging (fMRI): A neuroimaging technique that infers brain activity by measuring changes in oxygen levels in the blood.
Functional Magnetic Resonance Imaging (fMRI): Functional magnetic resonance imaging (fMRI): A neuroimaging technique that infers brain activity by measuring changes in oxygen levels in the blood.
Globus pallidus: A nucleus of the basal ganglia.
Gray matter: Composes the bark or the cortex of the cerebrum and consists of the cell bodies of the neurons (see also white matter).
Gray matter: The outer grayish regions of the brain comprised of the neurons’ cell bodies.
Gyri: (plural) Folds between sulci in the cortex.
Gyrus: A fold between sulci in the cortex.
Gyrus: (plural form, gyri) A bulge that is raised between or among fissures of the convoluted brain.
Hemoglobin: The oxygen-carrying portion of a red blood cell.
Hippocampus: (plural form, hippocampi) A nucleus inside (medial) the temporal lobe implicated in learning and memory.
Homo habilis: A human ancestor, handy man, that lived two million years ago.
Homo sapiens: Modern man, the only surviving form of the genus Homo.
Horizontal plane: A slice that runs horizontally through a standing person (i.e., parallel to the floor); slices of brain in this plane divide the top and bottom parts of the brain; this plane is similar to slicing a hamburger bun.
Hyperpolarization: A change in a cell’s membrane potential, making the inside of the cell more negative and decreasing the chance of an action potential.
Hypothalamus: Part of the diencephalon. Regulates biological drives with pituitary gland.
Immunocytochemistry: A method of staining tissue including the brain, using antibodies.
Inhibitory postsynaptic potentials: A hyperpolarizing postsynaptic current that causes the membrane potential to become more negative and move away from the threshold of excitation.
Invasive Procedure: A procedure that involves the skin being broken or an instrument or chemical being introduced into a body cavity.
Ion channels: Proteins that span the cell membrane, forming channels that specific ions can flow through between the intracellular and extracellular space.
Ionotropic receptor: Ion channel that opens to allow ions to permeate the cell membrane under specific conditions, such as the presence of a neurotransmitter or a specific membrane potential.
Lateral geniculate nucleus: (or LGN) A nucleus in the thalamus that is innervated by the optic nerves and sends signals to the visual cortex in the occipital lobe.
Lateral sulcus: The major fissure that delineates the temporal lobe below the frontal and the parietal lobes.
Lateralized: To the side; used to refer to the fact that specific functions may reside primarily in one hemisphere or the other (e.g., for the majority individuals, the left hemisphere is most responsible for language).
Lesion: A region in the brain that suffered damage through injury, disease, or medical intervention.
Lesion studies: A surgical method in which a part of the animal brain is removed to study its effects on behavior or function.
Lesions: Abnormalities in the tissue of an organism usually caused by disease or trauma.
Limbic system: Includes the subcortical structures of the amygdala and hippocampal formation as well as some cortical structures; responsible for aversion and gratification.
Limbic System: Includes the subcortical structures of the amygdala and hippocampal formation as well as some cortical structures; responsible for aversion and gratification.
Limbic system: A loosely defined network of nuclei in the brain involved with learning and emotion.
Magnetic resonance imaging: Or MRI is a brain imaging noninvasive technique that uses magnetic energy to generate brain images (also see fMRI).
Magnification factor: Cortical space projected by an area of sensory input (e.g., mm of cortex per degree of visual field).
Medulla oblongata: An area just above the spinal cord that processes breathing, digestion, heart and blood vessel function, swallowing, and sneezing.
Metabolite: A substance necessary for a living organism to maintain life.
Motor cortex: Region of the frontal lobe responsible for voluntary movement; the motor cortex has a contralateral representation of the human body.
Myelin: Fatty tissue, produced by glial cells (see module, “Neurons”) that insulates the axons of the neurons; myelin is necessary for normal conduction of electrical impulses among neurons.
Myelin Sheath: Fatty tissue, that insulates the axons of the neurons; myelin is necessary for normal conduction of electrical impulses among neurons.
Myelin sheath: Substance around the axon of a neuron that serves as insulation to allow the action potential to conduct rapidly toward the terminal buttons.
Nervous System: The body’s network for electrochemical communication. This system includes all the nerves cells in the body.
Neural crest: A set of primordial neurons that migrate outside the neural tube and give rise to sensory and autonomic neurons in the peripheral nervous system.
Neural induction: A process that causes the formation of the neural tube.
Neural plasticity: The ability of synapses and neural pathways to change over time and adapt to changes in neural process, behavior, or environment.
Neuroblasts: Brain progenitor cells that asymmetrically divide into other neuroblasts or nerve cells.
Neuroepithelium: The lining of the neural tube.
Neurons: Individual brain cells
Neuroscience methods: A research method that deals with the structure or function of the nervous system and brain.
Neurotransmitters: Chemical substance released by the presynaptic terminal button that acts on the postsynaptic cell.
Neurotransmitters: Chemical substance released by the presynaptic terminal button that acts on the postsynaptic cell.
Nomenclature: Naming conventions.
Noninvasive procedure: A procedure that does not require the insertion of an instrument or chemical through the skin or into a body cavity.
Nucleus: Collection of nerve cells found in the brain which typically serve a specific function.
Occipital lobe: The back part of the cerebrum, which houses the visual areas.
Occipital Lobe: The back most (posterior) part of the cerebrum; involved in vision.
Occipital lobe: The back most (posterior) part of the cerebrum; involved in vision.
Oxygenated hemoglobin: Hemoglobin carrying oxygen.
Parasympathetic nervous system: A division of the autonomic nervous system that is slower than its counterpart—that is, the sympathetic nervous system—and works in opposition to it. Generally engaged in “rest and digest” functions.
Parasympathetic nervous system (PNS): One of the two major divisions of the autonomic nervous system, responsible for stimulation of “rest and digest” activities.
Parietal lobe: The part of the cerebrum between the frontal and occipital lobes; involved in bodily sensations, visual attention, and integrating the senses.
Parietal lobe: An area of the cerebrum just behind the central sulcus that is engaged with somatosensory and gustatory sensation.
Parietal Lobe: The part of the cerebrum between the frontal and occipital lobes; involved in bodily sensations, visual attention, and integrating the senses.
Peripheral nervous system: The part of the nervous system that is outside the brain and spinal cord.
Peripheral Nervous System: All of the nerve cells that connect the central nervous system to all the other parts of the body.
Phrenology: A now-discredited field of brain study, popular in the first half of the 19th century that correlated bumps and indentations of the skull with specific functions of the brain.
Pons: A bridge that connects the cerebral cortex with the medulla, and reciprocally transfers information back and forth between the brain and the spinal cord.
Positron: A particle having the same mass and numerically equal but positive charge as an electron.
Positron Emission Tomography: (or PET) An invasive procedure that captures brain images with positron emissions from the brain after the individual has been injected with radio-labeled isotopes.
Positron Emission Tomography (PET): A neuroimaging technique that measures brain activity by detecting the presence of a radioactive substance in the brain that is initially injected into the bloodstream and then pulled in by active brain tissue.
Positron emission tomography (PET): A neuroimaging technique that measures brain activity by detecting the presence of a radioactive substance in the brain that is initially injected into the bloodstream and then pulled in by active brain tissue.
Primary Motor Cortex: A strip of cortex just in front of the central sulcus that is involved with motor control.
Primary Somatosensory Cortex: A strip of cerebral tissue just behind the central sulcus engaged in sensory reception of bodily sensations.
Psychophysiological methods: Any research method in which the dependent variable is a physiological measure and the independent variable is behavioral or mental (such as memory).
Resting membrane potential: The voltage inside the cell relative to the voltage outside the cell while the cell is a rest (approximately -70 mV).
Rostrocaudal: A front-back plane used to identify anatomical structures in the body and the brain.
Sagittal plane: A slice that runs vertically from front to back; slices of brain in this plane divide the left and right side of the brain; this plane is similar to slicing a baked potato lengthwise.
Sodium-potassium pump: An ion channel that uses the neuron’s energy (adenosine triphosphate, ATP) to pump three Na+ ions outside the cell in exchange for bringing two K+ ions inside the cell.
Soma: Cell body of a neuron that contains the nucleus and genetic information, and directs protein synthesis.
Soma: Cell body of a neuron that contains the nucleus and genetic information, and directs protein synthesis.
Somatic nervous system: A part of the peripheral nervous system that uses cranial and spinal nerves in volitional actions.
Somatosensory (body sensations) cortex: The region of the parietal lobe responsible for bodily sensations; the somatosensory cortex has a contralateral representation of the human body.
Spatial resolution: A term that refers to how small the elements of an image are; high spatial resolution means the device or technique can resolve very small elements; in neuroscience it describes how small of a structure in the brain can be imaged.
Spatial resolution: The degree to which one can separate a single object in space from another.
Spatial Resolution: A term that refers to how small the elements of an image are; high spatial resolution means the device or technique can resolve very small elements; in neuroscience it describes how small of a structure in the brain can be imaged.
Spina bifida: A developmental disease of the spinal cord, where the neural tube does not close caudally.
Spines: Protrusions on the dendrite of a neuron that form synapses with terminal buttons of the presynaptic axon.
Split-brain Patient: A patient who has had most or all of his or her corpus callosum severed.
Split-brain patient: A patient who has had most or all of his or her corpus callosum severed.
Subcortical: Structures that lie beneath the cerebral cortex, but above the brain stem.
Sulci: (plural) Grooves separating folds of the cortex.
Sulcus: (plural form, sulci) The crevices or fissures formed by convolutions in the brain.
Sulcus: A groove separating folds of the cortex.
Sympathetic nervous system: A division of the autonomic nervous system, that is faster than its counterpart that is the parasympathetic nervous system and works in opposition to it. Generally engaged in “fight or flight” functions.
Sympathetic nervous system (SNS): One of the two major divisions of the autonomic nervous system, responsible for stimulation of “fight or flight” activities.
Synapse: Junction between the presynaptic terminal button of one neuron and the dendrite, axon, or soma of another postsynaptic neuron.
Synapses: Junction between the presynaptic terminal button of one neuron and the dendrite, axon, or soma of another postsynaptic neuron.
Synaptic gap: Also known as the synaptic cleft; the small space between the presynaptic terminal button and the postsynaptic dendritic spine, axon, or soma.
Synaptic Gap: Also known as the synaptic cleft; the small space between the presynaptic terminal button and the postsynaptic dendritic spine, axon, or soma.
Synaptic vesicles: Groups of neurotransmitters packaged together and located within the terminal button.
Temporal Lobe: The part of the cerebrum in front of (anterior to) the occipital lobe and below the lateral fissure; involved in vision, auditory processing, memory, and integrating vision and audition.
Temporal lobe: The part of the cerebrum in front of (anterior to) the occipital lobe and below the lateral fissure; involved in vision, auditory processing, memory, and integrating vision and audition.
Temporal lobe: An area of the cerebrum that lies below the lateral sulcus; it contains auditory and olfactory (smell) projection regions.
Temporal Resolution: A term that refers to how small a unit of time can be measured; high temporal resolution means capable of resolving very small units of time; in neuroscience it describes how precisely in time a process can be measured in the brain.
Temporal resolution: The degree to which one can separate a single point in time from another.
Temporal resolution: A term that refers to how small a unit of time can be measured; high temporal resolution means capable of resolving very small units of time; in neuroscience it describes how precisely in time a process can be measured in the brain.
Terminal button: The part of the end of the axon that form synapses with postsynaptic dendrite, axon, or soma.
Thalamus: A part of the diencephalon that works as a gateway for incoming and outgoing information.
Threshold of excitation: Specific membrane potential that the neuron must reach to initiate an action potential.
Transcranial direct current stimulation (tDCS): A neuroscience technique that passes mild electrical current directly through a brain area by placing small electrodes on the skull.
Transcranial magnetic stimulation (TMS): A neuroscience technique whereby a brief magnetic pulse is applied to the head that temporarily induces a weak electrical current that interferes with ongoing activity.
Transduction: A process in which physical energy converts into neural energy.
Transverse plane: See “horizontal plane.”
Visual hemifield: The half of visual space (what we see) on one side of fixation (where we are looking); the left hemisphere is responsible for the right visual hemifield, and the right hemisphere is responsible for the left visual hemifield.
Voltage: The difference in electric charge between two points.
Wernicke’s area: A language area in the temporal lobe where linguistic information is comprehended (Also see Broca’s area).
White matter: Regions of the nervous system that represent the axons of the nerve cells; whitish in color because of myelination of the nerve cells.
White matter: The inner whitish regions of the cerebrum comprised of the myelinated axons of neurons in the cerebral cortex.
Working memory: Short transitory memory processed in the hippocampus.