New World cranial deformation practices: historical implications for pathophysiology of cognitive impairment in deformational plagiocephaly.
BACKGROUND
Throughout history, prehistoric and even some contemporary civilizations have practiced various forms of intentional and unintentional cranial deformation. Plagiocephaly can be the result of craniosynostosis, infant positioning, or other unintentional or intentional deformation.


METHODS
We reviewed the medical and anthropological literature and the anthropological collections of Arizona State University and the San Diego Museum of Man for evidence of cranial deformation and its possible physiological and cognitive side effects. Evidence of cranial shaping was also sought among art or stone work from representative cultures.


RESULTS
The anthropological record and literature attest to the presence of much more severe forms of deformation than that seen as a result of contemporary infant positioning. Despite this evidence, there is no anthropological evidence as to the possible cognitive effects that such deformation may have, although some evidence is reviewed that suggests a possible physiological mechanism for the same.


CONCLUSIONS
Because we can only view these cultures through the relics of time, any conclusions one might draw from the anthropological and historical record regarding the cognitive effects of head deformation can only be inferred through generalized observations and are tenuous. Nevertheless, there does not seem to be any evidence of negative effect on the societies that have practiced even very severe forms of intentional cranial deformation (e.g., the Olmec and Maya). On the other hand, the physical anthropology and the contemporary developmental literature suggest possible mechanisms for such an effect.
Lekovic
Gregory P
GP
Division of Neurological Surgery, Barrow Neurological Institute, St. Joseph's Hospital and Medical Center, Phoenix, Arizona 85013, USA.
Baker
Brenda
B
Lekovic
Jill M
JM
Preul
Mark C
MC
D003072:Cognition Disorders / Q000209:etiology / Q000266:history* / Q000503:physiopathology; D003466:Cultural Characteristics; D005006:Ethnicity / Q000266:history* / Q000523:psychology; D049668:History, 15th Century; D049669:History, 16th Century; D049670:History, 17th Century; D049671:History, 18th Century; D049672:History, 19th Century; D049673:History, 20th Century; D049690:History, Ancient; D049691:History, Medieval; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D049068:Plagiocephaly, Nonsynostotic / Q000150:complications / Q000208:ethnology / Q000266:history*