A muscle in a state of contraction that opposes the action of another muscle termed the antagonist. It is the prime mover or muscle directly responsible for a change in position of a part of the body. It can also be defined as one member of a group of muscles whose line of application produces …
Author Archives: Brian Hopkins
Akaike’s information criterion (AIC)
An indice used as an aid in choosingbetween competing statistical models. Formula-wise it is given as: -2Ln +2k or conversely 2k – 2Ln(L), where L isthe maximized log-likelihood and k the number of parameters or predictors inthe model (the likelihood function giving the probability of observing the data given aparticular set of model parameters, something that …
Agnosia
Complete or partial loss of the ability to recognise familiar objects or stimuli (including faces), usually as a result of brain damage, mostly to the parietal or occipital cortex. In addition to visual agnosia, there is auditory agnosia, an inability to recognise or understand the meaning of spoken words, and olfactory agnosia, an inability to …
Ages and Stages Questionnaire (ASQ)
Caregiver-report questionnaire to determine the extent to which children aremeeting or missing key developmental milestones in a variety of domains frombirth through 6 years-of-age. The ASQ spans five areas of development: communication,gross motor, fine motor, problem solving, and personal-social interaction. Distinct versions are available for different age groups, with some continuityto the content, even as …
Aggressive behavior
Use of force against someone. The force that is used can take different forms, such as physical, verbal, intellectual, emotional, social, economic, and spiritual. Other than testosterone, further factors that are involved in aggressive behavior include substance abuse, and less obvious ones such as chronic obstructive pulmonary disease, dementia, stroke, and urinary tract infections. At …
Age-crime curve
Age differences in the frequency of criminal behaviour. What such a curve shows is a rapid increase in deviant behaviour during adolescence, followed by an equally rapid decrease in such behavior (see figure below). Its onset has been attributed to increases in testosterone levels, and to environmental influences such as deviant families, deviant peers, and …
Agentic processes
In neo-Piagetian skill theory, the capacity to exert control over action, thought or feeling. Infants act as agents soon after birth as they begin to exert control over simple reflexes and action elements. Although individuals exert control over their actions, controlled action always occurs under coactive control of the social context and the biological medium …
Affordance
A neologism devised by James J. Gibson (1904-1979). Defined as functional possibilities of an object or environmental layout relative to what an individual can do with respect to them. It involves two sorts of properties: objective properties (what something affords depends on its physical characteristics) and subjective properties (what something affords depends in addition on …
Aerobic respiration
Respiration occurring in the presence of oxygen. It ensures that foodstuffs, usually carbohydrates, are completely oxidised to carbon dioxide and water, with the release of chemical energy. Most organisms use aerobic respiration, except bacteria and yeasts. It is contrasted with anaerobic respiration. See Anerobic respiration, Krebs cycle (or tri-carboxylic acid, TCA, cycle), Maximal aerobic power
Affixes
Inflections or morphemes attached either to the beginnings (prefixes), ends (suffixes), or middles (infixes) of words. Adding prefixes and suffixes to word roots is a feature of so-called agglutinating languages (those in which have a morphological system in which words as a rule are polymorphemic and where each morpheme corresponds to a single lexical meaning). …