Vocabulary
Ablation
Surgical removal of brain tissue.
Axial plane
See “horizontal plane.”
Basal ganglia
Subcortical structures of the cerebral hemispheres involved in voluntary movement.
Brain stem
The “trunk” of the brain comprised of the medulla, pons, midbrain, and diencephalon.
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.
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 convolutions characteristic of the mammalian brain.
Cerebral hemispheres
The cerebral cortex, underlying white matter, and subcortical structures.
Cerebrum
Usually refers to the cerebral cortex and associated white matter, but in some texts includes the subcortical structures.
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.
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.
Electroencephalography (EEG)
A neuroimaging technique that measures electrical brain activity via multiple electrodes on the scalp.
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.
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.
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.
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.
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.
Limbic system
Includes the subcortical structures of the amygdala and hippocampal formation as well as some cortical structures; responsible for aversion and gratification.
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.
Nomenclature
Naming conventions.
Occipital lobe
The back most (posterior) part of the cerebrum; involved in vision.
Parietal lobe The part of the cerebrum between the frontal and occipital lobes; involved in bodily sensations, visual attention, and integrating the senses.
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.
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.
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.
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.
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
A groove separating folds of the cortex.
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 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.
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.
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.
White matter
The inner whitish regions of the cerebrum comprised of the myelinated axons of neurons in the cerebral cortex.