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Anterior specialization resulting in the concentration of sensory and neural organs in the head.
McGraw-Hill Dictionary of Scientific & Technical Terms, 6E, Copyright © 2003 by The McGraw-Hill Companies, Inc.
The following article is from The Great Soviet Encyclopedia (1979). It might be outdated or ideologically biased.



the intensified development of the cephalic portion of the body in bilaterally symmetric animals during the process of evolution. The head end of the body, which includes the oral orifice, is first to experience new objects in the environment. As a result, the sense organs (vision, olfaction, touch, and hearing, the latter being developed only in vertebrates) and the sections of the nervous system that regulate the sense organs and make up the brain are concentrated in the head end of the body. In vertebrates a skull has developed to protect the aforementioned organs. In invertebrates this protective function is performed by a hard external cover. In cephalopods the brain is protected by a cartilage capsule.

The Great Soviet Encyclopedia, 3rd Edition (1970-1979). © 2010 The Gale Group, Inc. All rights reserved.
References in periodicals archive ?
Concepts with multiple meanings are introduced without clarification by historic figures ("cephalization" p.
And good fits becoming evident as we proceed, even in unlikely crossings (such as, perhaps, cephalization with cubism), are consiliences.
The cephalization of economic life brought about by the industrial revolution was not sui generis.
In such cases we say the organism has undergone cephalization and
Centralization of this deciding and controlling function is imperative, a process of 'cephalization', such as has taken place in the evolution of organic life, is inevitable, and for the same reasons as in the case of biological evolution".
This lack of cephalization is a derived feature diagnostic for the pentamerally symmetrical echinoderms.
Specifically, the adult nervous systems of nudibranchs manifest a high degree of cephalization with fusion of the cerebral and pleural ganglia, close proximity of the pedal ganglia with the cerebropleural ganglia, and an absence of major posterior ganglia.