An epigenetic theory of hemispheric specialization: the role of prenatal sensori-motor experience in the development of turning bias and spatial orientation in bobwhite quail (Colinus virginianus)

This study examined the effects of prenatal sensory and motor experience on the development of spatial orientation and turning bias in bobwhite quail. The theory presented here describes hemispheric specialization as the result of probabilistic events in the developing organism's prenatal environment; in particular, activity and experience in the final stages of prenatal development appear critical. Models and definitions of behavioral asymmetry, hemispheric specialization, and structural lateralization are reviewed. The results of Experiment 1 revealed a left-side turning bias in 85% of unmanipulated chicks. Experiments 2, 3, and 4 demonstrated that prenatal visual experience is a significant facilitator of population level left-side turning biases in bobwhite quail chicks. Experiment 5 investigated a potential underlying neurological basis for the bobwhite turning bias with unilateral injections of cycloheximide. The results of Experiment 5 suggest a left hemispheric specialization for the left-side turning bias. Furthermore, the results of Experiments 2 and 3 suggest that the asymmetrical hatching behaviors of the bobwhite quail are also a significant canalizing influence on the development of turning bias. The findings of this study are discussed in terms of an epigenetic theory of the development of hemispheric specialization and questions are raised as to the efficacy of laterality indexes as a reliable quantification of degree of hemispheric lateralization.

Name thesis:degree_name

Ph. D.

Level thesis:degree_level

doctoral

Discipline thesis:degree_discipline

Psychology

Department dc:contributor.department

Psychology

Grantor dc:publisher

Virginia Tech

Year dc:date.issued

1995

Author dc:creator

• Casey, Michael Bernard

Chair dc:contributor.committeechair

• Lickliter, Robert E.

Committee members dc:contributor.committeemember

• Cooper, Robin K. Panneton
• Denbow, D. Michael
• Sgro, Joseph A.
• Zeskind, Philip Sanford

• psychology
• lateralization
• prenatal
• turning bias
• quail

Statement dc:rights

• In Copyright

Licence dc:rights.uri

• http://rightsstatements.org/vocab/InC/1.0/

Language dc:language.iso

en

Dc Identifier Other

etd-10262005-143514

OAI identifier oai:identifier

oai:vtechworks.lib.vt.edu:10919/40212