cerebrum(redirected from cerebrums)
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cer·e·brums(ser'ĕ-brŭm, sĕ-rē'brŭm; -bră; -brŭmz), [TA] Although the pronunciation of this word with stress on the first syllable is classically correct, the second syllable is often stressed in the U.S.
cerebrum/cer·e·brum/ (ser´ĕ-brum) (sĕ-re´brum) the main portion of the brain, occupying the upper part of the cranial cavity; its two hemispheres, united by the corpus callosum, form the largest part of the central nervous system in humans. The term is sometimes applied to the postembryonic forebrain and midbrain together or to the entire brain.
brainThe epicentre of the central nervous system, which is located within the cranial vault and divided into the right and left hemispheres. The brain functions as a primary receiver, organiser and distributor of information for the body; it is the centre of thought and emotion, co-ordinates and controls bodily activities and interprets sensory visual, auditory, olfactory, tactile and other information.
cer·e·brum, pl. cerebra (ser'ĕ-brŭm, -bră) [TA]
cerebrum(sĕr′ĕ-brŭm) (sĕr-ē′brŭm) [L.]
The cerebrum develops from the telencephalon, the most anterior portion of the prosencephalon or forebrain.
Each cerebral hemisphere consists of three primary portions—the rhinencephalon or olfactory lobe, the corpus striatum, and the pallium or cerebral cortex. The cortex is a layer of gray matter that forms the surface of each hemisphere. The part in the rhinencephalon (phylogenetically the oldest) is called the archipallium; the larger nonolfactory cortex is called the neopallium. The cerebrum contains two cavities, the lateral ventricles (right and left) and the rostral portion of the third ventricle. The white matter of each hemisphere consists of three kinds of myelinated fibers: commissural fibers, which pass from one hemisphere to the other; projection fibers, which convey impulses to and from the cortex; and association fibers, which connect various parts of the cortex within one hemisphere.
Lobes: The principal lobes are the frontal, parietal, occipital, and temporal lobes and the central (the insula or island of Reil). Basal ganglia: Masses of gray matter are deeply embedded within each hemisphere. They are the caudate, lentiform, and amygdaloid nuclei and the claustrum. Fissures and sulci: These include the lateral cerebral fissure (of Sylvius), the central sulcus (of Rolando), the parieto-occipital fissure, the calcarine fissure, the cingulate sulcus, the collateral fissure, the sulcus circularis, and the longitudinal cerebral fissure. Gyri: These include the superior, middle, and inferior frontal gyri, the anterior and posterior central gyri, the superior, middle, and inferior temporal gyri, and the cingulate, lingual, fusiform, and hippocampal gyri.
The cerebrum is concerned with sensations (the interpretation of sensory impulses) and all voluntary muscular activities. It is the seat of consciousness and the center of the higher mental faculties such as memory, learning, reasoning, judgment, intelligence, and the emotions. See: illustration
On the basis of function, several areas have been identified and located. Motor areas in the frontal lobes initiate all voluntary movement of skeletal muscles. Sensory areas in the parietal lobes are for taste and cutaneous senses, those in the temporal lobes are for hearing and smell, and those in the occipital lobes are for vision. Association areas are concerned with integration, analysis, learning, and memory.