Bryant 

Cognitive development refers to the gradual unfolding of the child's abilities to think, to reason, and to use language. At the other end of the life-span, cognitive development looks at how certain cognitive capacities such as memory can diminish with age. 

Longitudinal. Like age-based cross-sectional methods, this approach is designed to provide data on how people change over time. However, it overcomes the methodological problems of cross-sectional studies by making repeated measures on the same group of people over long periods of time. This approach also allows researchers to make detailed observations of major points of change in people's lives (if the times between observations are relatively short). This research would typically take place over a period of some years (or even decades). Although it is a very powerful way of looking at age-related changes, it clearly also involves a great commitment in time on behalf of the researchers (and willingness on the part of their participants to continue participating in the research). Perhaps the best known longitudinal studies are cohort studies that aim to follow people born in one week from birth throughout their lives. 

Social Constructionist. The basic idea underlying all social constructionist theories is that the ways in which we understand the world and the things we consider true are not just 'natural' ways of understanding reality, but are actively constructed between people as they go about their everyday lives and interact with each other. These 'ways of knowing', therefore, are inextricably part of a social process. This perspective suggests that all human knowledge – even knowledge that seems to be just an objective description of 'reality', such as physics or chemistry – is in fact constructed by people within their own particular historical and social contexts. Social constructionism falls within the broad approach to studying social psychology called 'sociological social psychology' (SSP). This fundamentally disagrees with the approach taken by experimental social psychology, which tackles social psychology by establishing the principles governing individual behaviour, and then seeing how these are modified in a social setting, a position called 'psychological social psychology' (PSP). (See EXPERIMENTAL SOCIAL PSYCHOLOGY). SSP approaches have quite a different focus. Instead of seeing the social context as simply another 'variable', they ask questions such as 'in a particular social setting, how do the social and cultural practices actually act to construct the individual, as he or she develops from childhood?'. The social worlds we live in are seen as 'interpretive networks', continually being constructed and reconstructed by individuals, groups, and institutions in interaction with each other. \n\nSocial constructionists are interested in how individual behaviour is inextricably linked with its social context, and in fact frequently emerges from that context. Most of human action is seen as social interaction, modifying even those of our activities which we may think we have created at a purely individual level, or which arise from 'biological instincts'. This viewpoint tends to make social constructionists critical of perspectives such as humanistic, with its much greater emphasis on the individual's capacity to create and modify their own world view. However, it would be a mistake to see social constructionism as taking a position of 'sociological determinism', seeing people as simple pawns of their social context. People are indeed seen by social constructionists as making active choices – however, the range of choices available, and how they are conceptualised, is seen as structured by the social materials available (although these 'social materials' are themselves seen as subject to a continual process of renegotiation and change).\nSocial constructionists argue that what is accepted as knowledge at any level – scientific, cultural or social – and in any area, is a social process. Knowledge is therefore seen as an expression of the particular social and historical context in which it is produced - what is taken to be 'true' or 'real' is always produced and sustained by social processes. This is applied especially to current taken-for-granted knowledge that seems most 'obvious', e.g. the 'natural' distinctions between different genders. Social constructionists would not, of course, deny the existence of clear physiological differences – but what they would be particularly interested in was how these differences are made sense of in different societies, and the implications for people's identity and way of life. They would argue that what most frequently has the greatest impact on people's sense of self and social lives are not what 'exists', but how it is conceptualised in that particular society. Hence a particular emphasis is placed on the role of language in constructing agreed social 'realities'. For example, the experience of being gay within those societies that see it as immoral (and perhaps illegal), compared with those societies that are quite comfortable with gay lifestyles. Note that this doesn't just vary with geography, but also historical period (e.g. compare British laws against male homosexuality nowadays, compared to just forty years ago). Another example might be whether we call someone a 'freedom fighter' or a 'terrorist'. Although these two terms can refer to the same person, each constructs a totally different way of viewing that person and the world. The language we use justifies particular responses to people and to situations, and plays a major role in constructing 'power relations' between people. There is an interesting contrast between social constructionist and psychometric views of identity. Instead of seeing identity as relatively fixed, identities are seen as shifting over time and between different socio-cultural contexts. Identity is therefore seen as historically and culturally specific, and dynamic, in that it is seen as constantly in the process of being 'renegotiated' in social interaction.\nIn contrast to most experimental research, social constructionism tends to use qualitative data, taken from naturalistic settings (i.e. from people's everyday lives and social interactions). This can involve looking at social representations of everyday concepts, or analysis of people's 'discourses' (i.e. those ways of thinking and talking about issues which are currently available in an individual's particular culture). These discourses are seen as the processes by which people construct meanings, and their study is called discourse analysis.