More academic definitions from psychologists, educational authorities and neuroscientists are almost as varied. Definitions from these academic sources include: “The ability of an individual to use a variety of cognitive and non-cognitive capabilities to formulate goals, logically work towards achieving these goals, and adapt to the demands of the environment. ” (Snowman, Dobozy, Scevak, dryer, Bartlett & Biehler, 2009, p. 10); “The ability to acquire knowledge, think and plan, monitor cognitive processes and determine what is to be done. ” (Mclnerney and Mclnerney, 2006, p. 574); and “Intelligence is a very general capability that, among other things, involves the ability to reason, plan, solve roblems, think abstractly, comprehend complex ideas, learn quickly and learn from experience. ” (Deary, Penke and Johnson, 2010, p. 202). A common theme in these definitions is that intelligence is about mental capabilities, but the biological and environmental determinants of mental processes are debated too.
The ‘Nature/Nurture’ debate requires some understanding of both neuroscience and socio-cultural arguments (Model, 2010). Mclnerney and Mclnerney (2006) discuss the impacts on physical and psychological development in humans of inherited and environmental factors, describing how an individual’s genetic potentials related to ntelligence, which are inherited from his/her biological parents, are modified by social and cultural influences such as socio-economic circumstances, ethnicity, diet, geographic location and child rearing practices.
Environmental factors such as these can facilitate, inhibit or compensate for inherited intellectual potential so that intelligence is not a result of genetics alone or of a rigid set of maturation processes. Whatever genes children are born with they are not passive in their environments, rather they react to and interact with their environments which impacts on genetic
Scientific advances in recent times mean that geneticists and neuroscientists have been investigating structural (genes and brain) and functional (brain activity) aspects of the human genome and brain in order to determine biological influences on intelligence. Both these areas of research are incomplete and no single gene or specific brain region have been located which directly determine intelligence (Deary et al 2010). Investigating the intricate, interconnected biological determinants alone does not address the issue of environmental influences on intelligence, and what are he relative influences of nature and nurture?
Gottfredson and Saklofske (2009), while agreeing that “it is well established that intelligence is a product of both hereditary and environmental factors and their interaction” (p. 184), go on to claim that the balance is 80% hereditary to 20% environmental. Model (2010) is explicit in stating that accumulated findings of intelligence research show that intelligence is heritable to a considerable degree and that environmental factors have much less influence.
Plomin and Spinath (2004) describe how some studies indicate that the balance is two thirds genetic to one hird environmental, but caution that “we create our experiences in part for genetic reasons… (but must) recognise the active role we play in selecting, modifying, and creating our own environments” (p. 114). These authors also state that care needs to be taken when making inferences from studies regarding the heritability of intelligence because correlations between biology and behaviour doesn’t mean that biology causes behaviour.
Cianciolo and Sternberg (2008) emphasise that while further genetic and brain research are needed to clarify the specific biological eatures directly related to intelligence, there also needs to be more detailed and reliable evidence about exactly which, and how, environmental factors impact on intelligence because, as Plomin and Spinath (2004) state, research targeting either ‘nature’ or ‘nurture’ separately is invalid as it is impossible to “disentangle genetic and environmental influences” (p. 12). Given the varied definitions of intelligence it is not easy to separate theories related to intelligence and those related to cognition. Abandoning early 20th century concepts that children are passive receivers of earning, by the middle of the century cognitive development theorists Jean Piaget and Lev Wgotsky proposed that children are active participants in learning, constructing new knowledge and mental processes by building on the knowledge and processes they have developed since birth.
Psaltis, Duveen and Perret-Clermont (2009) explain that in Piaget’s structural and ages/stages approaches to cognitive processes a child is considered as a purely abstract subject, whereas Wgotskys contextual approach recognises the child as a social-psychological subject who participates in socially and culturally constructed patterns of thinking and learning. Historically, “the field of intelligence is relatively young – it has only existed since the latter half of the nineteenth century’ (Cianciolo and Sternberg, 2008, p. 136).
Qualifying and quantifying human intelligence have become topics of great social interest not only for academics, psychologists, researchers and educators but to the underestimated; people’s life chances are greatly influenced by the measurement and classification of an individual’s intelligence (Stanovich, 2009). “Intelligence testing is a way of excluding many individuals, particularly from disadvantaged groups that re labelled as intellectually disabled, from participating in mainstream society. ” (Mclnerney and Mclnerney, 2006, pp. 4-85). In the late 19th century Anglo-Europeans were convinced of their ‘racial superiority and looked for religious and scientific ‘evidence’ of this. Assessment of relative intelligence between ethnic groups was one means used to rationalise these arguments. Manipulating pseudo-scientific principles such as social Darwinism, eugenics and phrenology, researchers such as Galton devised intelligence tests to demonstrate the cultural, moral and intellectual superiority of the White races’ (Wadham, Pudsey and Boyd, 2007).
The rise in interest, since that time, in defining and measuring intelligence has seen both reliable and unreliable research outcomes. “Intelligence tests, like various practical innovations from the physical, genetic and biological sciences, may be used for the greater good or misused for selfish reasons and/or political gain” (Wilhelm and Engle, 2005, p. 334). A chronology of intelligence testing indicates changes in concepts of what intelligence is.