Myelinated axons of granular cells that run horizontally near the surface of the cerebellar cortex and perpendicular to the dendritic fields of Purkinje cells, and that make excitatory (glutamate) axodendritic synapses on spines of the distal dendrites of Purkinje cells, as well as those of basket, Golgi type II and stellate inhibitory interneurons – at …
Category Archives: Uncategorized
Paradigm (mechanistic) ‚Üì Principles (e.g., newborn
a bundle of reflexes) ‚aa Theory (e.g., reflexology) ‚aa Laws (e.g., law of effect) ‚aa
Paradigm shift
A concept put forward by Thomas S. Kuhn (1922-1996) in his book The structure of scientific revolutions (1962) to denote a rapid and discontinuous change from one paradigm to another (i.e., a ‘scientific revolution’) due to a growing dissatisfaction with the guiding principles and theory in a particular scientific community. A frequently cited example is …
Paradigm
A vague term with a number of different meanings. One interpretation resides with the introduction of the term into the history of science by Thomas S. Kuhn (1922-1996) in 1962, where it means something like a world view: a set of assumptions and values, almost metaphysical in nature, shared and agreed upon by a scientific community …
Pancreas
A glandular organ associated with the digestive system that secretes digestive enzymes in the small intestine as well as a number of hormones including insulin and glucagon that are secreted into the bloodstream. It is thus part of the digestive and endocrine systems in vertebrates. The pancreas is formed from the entoderm initially as a …
Panel studies
A research design in which a group of participants is selected without regard to risks and is followed repeatedly to determine factors related to developmental outcomes or later onset of diseases or other conditions (see below for a more technical definition). They are, thus, a form of longitudinal studies. The unit of analysis can vary …
Palmar grasp
Beginning at about 4 months-of-age, the infant will grasp an appropriate-sized object with the ulnar side of the palm, but without involvement of the thumb. A month of so later, the object is grasped with the the whole hand and thus secured in the middle of the palm, but there is still little or no …
Palaeontology
A branch of evolutionary biology that draws upon geology to study fossil fauna and flora and their ecologies in order to reconstruct phylogenetic relationships. Crucial to this enterprise are techniques for dating rock formations containing the fossils. Johann Friedrich Blumenbach (1752-1830) was the first to suggest the use of fossils to trace the age of …
Palate
The roof of the mouth in mammals that consists of the hard palate (anterior bony portion) and the soft palate (posterior muscular portion), which separates the oral and nasal cavities. The hard palate, encased in a mucous membrane, provides a surface against which the tongue can be moved and placed to enable sounds. Another function …
P400
A specific positive component of the event-related potential, thought to be elicited by faces, and observed in infants but not adults. It has been suggested to be a precursor to the negative component N170 compared to which it differs not only in polarity, but also peaks at a later latency. These peak latencies decrease from …