The control and manipulation of variables in order to test scientific theories. In laboratory-based experiments, it typically involves the manipulation of one variable while attempting to keep all others constant. Outside the laboratory, there are two other types of experiments, with less control over potential confounding variables. One is field experiments carried out in something …
Category Archives: Uncategorized
Expert opinion
The judgment of people considered by virtue of their learning and experience to know much more than is typical about a particular topic. Sometimes expert opinion is used to validate a measurement technique in the absence of other objective criteria. It includes the Delphi method. See Back-translation, Delphi method
Experimental embryology
Came to replace descriptive embryology in the middle of the 19th century as means of trying to identify experimentally the ‘mechanics’ of growth and development (the causal-analytic approach). Experimental manipulations included the selective destruction of tissues (Wilhelm Roux, 1850-1924; Hans Driesch, 1867-1941) or the transplantation of one body part to another part of the body …
Experience-expectant processes
Examples include overproduction of nerve cells, dendrites, and synapses prenatally that await fine-tuning and adjustment with first experiences postnatally involving, for instance, vision and hearing. See Experience, Experience-dependent processes, Systemogenesis
Experience
A widely used term that can refer to specific learning or other events that influence the course of development. Even more broadly, it has been taken to mean the contribution to development of the effects of stimulation from all available sources, both external and internal. None of these meanings is particularly satisfactory as they ignore …
Experience-dependent processes
The idea that the development and functioning of a system are shaped by its experience with the environment. It has been shown that many cortical areas develop in an experience-dependent way, and this idea has been taken up in different connectionist models of cognitive development. See Activity-dependent organization, Connectionist models, Constructivism, Experience, Experience-expectant processes, Intersensory …
Executive attention
An executive function ability to allocate attention in a way that is consistent with self-established goals and plans. Executive attention shows the most extended developmental changes, beginning in the late phases of infancy (18 months) and showing further changes throughout adolescence. See Attention, Executive function (EF)
Executive function (EF)
An umbrella term for the set of (neuro-) cognitive processes underlying flexible goal-directed responses to novel or complex situations. Such situations may involve: 1. planning and decision making, 2. error correction or troubleshooting, 3. initiation of novel sequences of actions, 4. danger or technical difficulty, or 5. need to overcome a strong habitual response. For some, …
Exception words
Words that contain irregular or very unusual grapheme-phoneme correspondences and cannot be read by sounding out (e.g., broad; yacht). See Action words, Grapheme-phoneme correspondences, Irregular words, Surface dyslexia
Evolutionary niche theory
A central tenet of the theory is that organisms modify their environments through a process called niche reconstruction or ecosystem engineering, the prime example being the activities of humans. Such modification can have profound effects on the distribution and abundance of organisms, the influence exerted by key species, the control of energy and material flows, …