hydrocephalus a postbirth condition characterized by fluid buildup around the brain, causing enlargement of the skull.
hypothalamus located below the cerebrum, the part of the brain that regulates body temperature and blood pressure.
idiot savant syndrome injury to the left hemisphere of the brain before, during, or after birth, causing the right hemisphere to enlarge and overcompensate. The sufferer has below-average left-brain functioning while having superhuman right-brain functioning.
inferior temporal gyrus in the temporal lobe, a fold involved in the recognition of objects.
intraparietal sulcus in the parietal lobe, a sulcus involved with language and the spelling of words.
lateral temporal cortex part of the temporal lobe involved in rhyming words.
left caudate portion of the left hemisphere involved in the process of back-and-forth switching of language use in bilingual people.
left inferior parietal cortex portion of the inferior parietal cortex involved in remembering unfamiliar faces.
left prefrontal cortex portion of the prefrontal cortex involved in remembering unfamiliar faces.
limbic lobe in the cerebrum, a lobe along the corpus callosum that contains the hippocampus and the cingulate gyrus.
limbic system in the upper brain stem, the old or reptilian brain that regulates hunger, thirst, sex, fighting, and basic emotion.
lobe one of five sections of the cerebrum—the frontal, limbic, parietal, occipital, and temporal—roughly divided by deep folding.
medial prefrontal cortex portion of the prefrontal cortex involved in social memory.
medulla oblongata the base of the brain; it regulates respiration and circulation.
meningitis inflammation of the covering of the brain.
microencephalon an abnormally small brain.
midbrain the portion of the brain that evolved after the hindbrain but before the forebrain, at the center of the head.
neglect a bizarre brain condition in which one hemisphere of the brain is damaged, causing the sufferer to perceive only one side of his environment.
neocortex the latest part of the brain to evolve, which includes the frontal, temporal, parietal, and occipital lobes, the heavily wrinkled outer layer of gray matter surrounding the cerebrum; it is known to be involved with conscious thought, language, and sensory perception.
neuron one of millions of specialized nerve cells that carry electrochemical impulses in the brain.
nucleus accumbens a grouping of neurons in the forebrain, involved in laughter, pleasure, and the placebo effect.
occipital lobe a lobe of the cerebrum, at the back of the head, the center of visual processing and reading skills.
operculum in the inferior frontal gyrus, a portion of the brain involved in the coordination of other brain areas.
orbitofrontal cortex part of the frontal lobe that has been implicated in regulating personality, social functioning, sense of responsibility, and mood.
paragraphia confused or distorted handwriting, caused by a brain condition.
parietal lobe the topmost lobe of the cerebrum, the center of sensory processing involving touch, pressure, pain, and temperature. Parts of the parietal lobe are also involved in attention and language.
Parkinson's disease a disease characterized by a shuffling gait, muscular rigidity, and uncontrollable tremors, thought to be due to a chemical imbalance in the brain.
pituitary attached to the hypothalamus, the gland that controls most of the hormones in the body.
pons a bundle of nerve fibers forming a bridge connecting the cerebellum and the medulla oblongata with the frontal lobe and other brain areas.
posterior parietal cortex the back portion of the parietal lobe, involved with face recognition and communicating socially.
prefrontal cortex at the very front of the frontal lobes, the portion of the brain involved in planning and decision making.
primary auditory cortex in a gyrus of the upper part of the temporal lobe, the part of the brain that processes sound.
primary motor cortex in the posterior of the frontal lobe, part of the brain involved in movement.
primary visual striate cortex in the occipital lobe, a processing area for visual images.
prosopagnosia the inability to recognize faces, including those of close family members, due to a brain condition. The sufferer may recognize the faces, however, as soon as he hears them speak.
reticular formation the part of the brain stem that regulates wakefulness and attention; it is the part of the brain that is shut off by anesthesia.
right parietal lobe part of the parietal lobe involved in processing numbers.
sinistrality the right-brain dominance over the left brain that produces left-handedness.
somatosensory neocortex in the parietal lobe, the area involved in processing touch sensations, including pressure, pain, positioning, and movement.
stereoanesthesia the inability to identify objects by touch, due to a brain condition.
sulcus any cleft or groove in the cerebrum.
superior temporal gyrus in the temporal lobe, a gyrus containing the primary auditory cortex.
supplementary motor area in the frontal lobe, a processing area for the control of movement.
suprachiasmatic nucleus part of the hypothalamus that regulates the body's circadian rhythm or biological clock.
synesthesia the confusion of senses (seeing sounds, hearing sights, etc.), a mysterious brain condition.
temporal lobe a lobe of the cerebrum, above the hindbrain, an area involved in hearing and the processing of memory and the naming of things.
thalamus at the top of the brain stem, the structure known as the "great relay station" because it conveys signals between the brain stem and the rest of the brain. It is also the origination of the sensations of heat, cold, pain, and pressure.
water on the brain hydrocephalus.
Wernicke's area auditory processing area involved in processing language.
wet brain a disease of chronic alcoholism, characterized by fluid buildup and mental deterioration.
white matter brain tissue composed largely of axons insulated with myelin. Women have more white matter in their neocortexes than men do, while men have more gray matter than women do. See gray matter.
Nerves
Names Function and Location
abducens supplies eye muscles
accessory supplies neck muscles, voice box,
shoulders
acoustic supplies the inner ear, deafness
results when damaged. Also known as the auditory nerve
alveolar supplies muscles of the mandible
and sensation to teeth
ampullary supplies inner ear and affects
balance
auricular sensation to the outer ear
axillary muscles of the shoulders and
NERVOUS SYSTEM 243
surrounding skin
buccal sensation to cheek, mucous
membranes of mouth and gums. Also known as buccinator cardiac supplies the heart
carotid in the neck, it serves the cranial
blood vessels and glands of the