Intervention by an adult to raise levels of pretend or sociodramatic play in pre-school children through suggestion, modeling, and provision of props and stimulation. There have been claims that play tutoring gives rise to improvements in competence broadly defined. However, it is possible that such improvements could be due to contact with adults due tutoring …
Author Archives: Brian Hopkins
Play fighting (or rough-and-tumble play)
A social form of play where the participants compete for some advantage. Even though competition is involved, the actions are attenuated to allow all participants to gain the advantage at least some of the time. Typically, it is more an activity of boys than girls. See Fantasy play, Fighting, Play, Sex roles, Sex-typing
Play
Although an unambiguous definition of this behavior is still in dispute, most definitions would include two criteria: an absence of an immediate utilitarian purpose and the presence of actions that are seemingly performed for their own sake (i.e., the process of the play is more important than any end point or goal). See Cognitive immaturity hypothesis, …
Plasticity (experiential)
Where organisms, objects or events have the capacity to change through experience. See Baldwin effect, Epigenesis, Equipotentiality, Experience, Learning, Plasticity (neural)
Plasticity (neural)
The property of the brain to reorganize itself after damage or in response to any developmental variation. It is a continuous process, especially during development, that results in short-term, medium-term and long-term remodelling in terms of both in the form and function of neurons and neural networks. See Axon retraction (or pruning), Brain …
Plantigrade locomotion
Locomotion with the plantar side of the foot in contact with the floor during the whole stance phase. It is a typical, and seemingly unique, pattern of early walking in humans, which over a number of years gradually transforms into digitigrade (heel-strike) locomotion. Human newborns when supported can be encouraged to make stepping movements that …
Placode
Local thickening in the embryonic ectodermal layer in the early embryo. The cells of the placed ordinarily constitute a primordial group from which a sense organ (e.g., lens placode) or neurons of sensory ganglia will be derived. Other parts of these ganglia arise from the neural crest. See Brain-derived neurotrophic factor (BDNF), Ectoderm, Ganglia, Neural …
Planned comparison
A priori determined comparison to be performed with a set of independent linear comparisons between levels of a factor in order to establish a significant main effect or interaction in an ANOVA. Doing so may result in a specific, but not an overall, difference. Carrying out planned comparisons can be based on theoretical and empirical …
Placenta previa
An obstetrical complication in which the placenta is implanted into a lower than usual segment of the uterus, partially or completely obstructing the cervical opening to the vagina. It is the main cause of antepartum haemorrhage (vaginal bleeding) and if severe enough may lead to a cesearian section or preterm birth, especially if it remains unresolved …
Placenta
In mammalian species, the organ in the uterus containing blood vessels that unites the fetus and mother, providing the fetus with oxygen and nutrients from maternal circulation while also removing waste products. Made by trophoblastic tissue and extra embryonic mesoderm. See Amnion (or amniotic sac), Chorion, Dizygotic twins, Mesoderm, Monozygotic twins, Nicotine, Ontogenetic adaptation, Pulsatility index (PI)