From the psychology literature, the work of de Ajuriaguerra et al (1964), using Piagetian tests on elderly people who have dementia, was the first to make such a link: ‘we have found in our patients all the stages of childhood described by Piaget’. More recently, Reisberg’s (1986) diagnostic ‘staging’ tool for Alzheimer’s disease (FAST) supports their hypothesis that deficits in dementia represent a reversal of Piaget’s developmental stages. The experiments of Stuart-Hamilton & McDonald (1996) using Piagetian tasks with unimpaired subjects, strengthen such a hypothesis. Most of this literature has been concerned with functional assessment alone, and indeed, a number of attempts have been made to construct assessment instruments based on a Piagetian hierarchy (McCurren and Ganong, 1984, Cole and Dastoor, 1987 and Sclan et al., 1990).

Piaget has also influenced the occupational therapy literature, though in considerably smaller measure. Würsten (1974) suggested that a Piagetian model of development had much to offer the concept of adaptation in occupational therapy. Unfortunately, he omitted to say how. Landsmann & Katz (1988) attempted to apply a Piagetian framework of assessment tests to psychiatric patients, but failed to offer a rationale for their assumption that developmental regression is at the root of mental illness. Both of these theories appear to have disappeared without trace in subsequent literature.

A much weightier contribution to professional advancement has been Mosey’s (1986) developmental frame of reference for occupational therapy, which is underpinned in some measure by Piagetian theory in its sequential linking of skills to stages of chronological development. Rather like Reisberg’s FAST instrument, it is designed to ‘stage’ an individual at a certain level of development and functional ability. Unlike the FAST, it is neither age- nor condition-specific, and is proposed for the field of mental health generally, to act as an indicator of functional level and as a guide for the appropriate delivery of therapy.

Also using Piaget as a base theory is the cognitive disability model of Allen (1985), whose six levels of cognitive ability are influenced by Piagetian concepts. This model was designed for occupational therapy with all cognitive disabilities, and this necessarily includes dementia, though Conroy’s (1996) evaluation of the model found the cognitive levels poorly articulated, and the model as a whole of limited utility in severe dementia.

A common thread running throughout this selection of literature is its primary concern with function and the assessment of function; it all appears to be driven by the question, ‘At what level of function is this impaired person now operating?’. We can make use of this material for assessment purposes if we wish, but we feel that it is actually more useful as an exploratory tool. That is how we shall use it in this chapter.

What appears to have been largely neglected in the body of literature surrounding Piaget’s work, is a study of the activity context in which his children developed their functional abilities, and the notion that such activity might actually be used in the context of therapeutic practice. A question which appears not to have been asked is, ‘If a person is at a given level of functioning, how might therapy be organised to accommodate that person?’. Chapter 8 looks specifically at this question.

Piaget was a prolific writer, with a very complex style, and in order to distil the key features of his theory, we have attempted a summary of his principal contentions. He categorised cognitive development in the child into four main stages (reflex, sensorimotor, representational, reflective), covering the ages 0–15. Each stage is again subdivided to demonstrate the progressive acquisition of cognitive skills as far as the individual’s mid-teens, at which point development is conceived to be complete. The following list is presented in reverse order to that set out by Piaget, i.e. 15 years (development complete) to 0 years (undeveloped), in order to offer a picture of cognitive decline as it might be viewed in dementia.

Before proceeding, it should perhaps be noted that in the years since Piaget published his findings, there has been an extensive and vigorous debate on their validity as a model of cognitive development. His ‘stage’ structure has come under particular criticism (Flavell, 1963 and Cohen, 1983), as have most of the experimental scenarios with his children upon which he formulated his conclusions (Donaldson, 1978 and Cohen, 1983).

Data emerging from subsequent research suggest that Piaget significantly underestimated the abilities of young children, and often overestimated the abilities of teenagers. The principal criticism is not so much that growing children do not pass through developmental hierarchies of object permanence, egocentricity, conservation, class relationship, etc., but that they pass through them rather differently, and at different levels of experience to those which Piaget suggests. One of Piaget’s main contentions was that children learn predominantly through the manipulation of their bodies and objects in the environment. Thought, logical thought, was the pre-eminent product, and was the determining factor in emotional and social experience (Cowan 1978). A child could only feel those feelings and engage in those relationships that his cognitive skills determined. Subsequent research suggests otherwise:

There are many other studies. Indeed, the 1970s seems to be a decade dedicated to the rejection of as many of Piaget’s claims as possible. What is particularly interesting, however, is that none of these studies invalidates Piaget’s theory, nor refutes his claims out of hand. What they do achieve, in pointing up his omissions, is a highlighting of matters of critical importance to those concerned with child development. For example, information must make sense to a child, and be culturally appropriate, for him to be able to mobilise appropriately those skills at his disposal. The way a situation is described and materials presented, has a considerable impact upon a child’s comprehension of a task. Thus, social setting (the people involved in a situation) also has a bearing on the ability to accomplish tasks. Training is important; a child’s familiarity with materials and procedures will maximise the demonstration of his abilities.