This research focused on the issue of children's understanding of the pretend-reality distinction. In particular, it investigated several features of the availability hypothesis (Harris, Brown, Marriott, Whittall & Harmer, 1991; Johnson & Harris, 1994) and the pretence continuation account (Golomb & Galasso, 1995) which have been previously offered as competing explanations for children's behaviours during pretence. Specifically, the experiments reported here explored the role of differing forms of affect in both of these accounts and assessed the constraining influence of empirical evidence of reality on the effects of increased cognitive availability. To this end, a series of seven related experiments were conducted in which four to seven year old children (N = 591) were asked to pretend about the contents of empty boxes. The children's behaviours on a series of box selection tasks were then observed under conditions of differing affect and varying levels of empirical evidence (experiments 1 to 5). The children's spontaneous behaviours were also video recorded (experiments 6 and 7). Taken together, the results suggest that there are interactions between individual differences, age, affect and levels of empirical evidence which predict children's propensity towards making pretend-reality confusions. In relation to previous explanations of children's behaviour, the pretence continuation account (Golomb & Galasso, 1995) is unable to explain the complexity of the current findings and the results are instead more consistent with an account involving individual differences such as that proposed by Johnson and Harris (1994). However, there are two crucial contributions which the experiments reported here can make to these explanations. First, there are developmental changes which take place between four and seven years of age in relation to pretend-reality understanding and these changes interact with the individual differences identified by Johnson and Harris (1994). Second, the present data provide evidence of the central role played by affect in children's pretence. Overall, this thesis offers an account of children's understanding of the distinction between pretence and reality which incorporates both developmental and individual differences.

The master thesis deals with the importance of the book in evolution of the children's imagination. The first part includes short introduction to problems of children's imagination. The second part is engaged in ontogeny of child from prenatal period to the middle childhood and in progress of key competences. It analyzes selected psychological approaches, which had the imagination as a subject of the research. The thesis explains and defines basic terms and processes of the imagination. It deals with a specific phenomenon of the children's imagination and with the evolution of the imagination. The third part introduces typical children's literature, directs on the traditional fairytale and it specifies problems of the literary characters too. It describes the historical development of the Czech book illustration, importance of the illustration in books for children and it also describes children's drawings. The fourth part applies all of previous pieces of knowledges into the work experience in kindergarten. It also describes relations between child and school or child and book. The final part of the master thesis includes summary of the information. [Author's abstract].