Cephalization | definition of cephalization by Medical dictionary
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1. Evolutionary tendency for important functions of the nervous system to move forward in the brain.
2. Initiation and concentration of the growth tendency at the anterior end of the embryo.
3. The antigravitational redistribution of pulmonary blood flow that occurs with heart failure, caused by increased vascular resistance in the dependent part of the lung, a consequence of pulmonary venous hypertension; usually described on the basis of relative vascular size on chest radiography.
An evolutionary trend in the animal kingdom toward centralization of neural and sensory organs in the head or anterior region of the body.
cephalization the development of the head of an organism during evolution. The development is largely associated with a concentration of sense organs at the front of an animal (see BRAIN). The complexity of the head region depends on the habits of the animal; highly active, free-living animals have the best-developed cephalization requiring maximum detection of the environment at the front, whereas sedentary forms normally have less well-developed heads.
References in periodicals archive
However humans are not unique in possessing intelligence and there is a general trend in evolution toward greater intelligence from the beginnings of cephalization
in invertebrates to the progressive advancement in cranial capacity of mammals.
This lack of cephalization
is a derived feature diagnostic for the pentamerally symmetrical echinoderms.
of the vasculature is not very helpful in the ICU setting because many films are obtained in the supine position, which redistributes vascular volumes.
When serial Doppler assessments subsequently demonstrate loss of this cephalization
of blood flow, they provide a guide as to when to deliver the baby to maximize neonatal outcome.