The aim of this research was to test empirically Elkind’s (1967, 1970, 1978) Piagetian theoretical formulation for the developmental nature of adolescent egocentrism. The contribution of this study is threefold because it includes: 1) Pubertal development (with a distinction between status and timing), which has been systematically ignored by other investigators; 2) a broad age range (11 18 yea...

The present study was designed to find out to what extent imaginary companions are created in the diaries of adolescents. A total of 241 adolescents aged 12 to 17 years were investigated to determine the incidence as well as the characteristics and functions of such fictitious individuals in this age group. Content analysis of data obtained from questionnaires revealed that the imaginary compan...

Is the presence of foveal stimulation a necessary prerequisite for rhesus monkeys to perform visually guided eye movements? To answer this question, we trained two rhesus monkeys to direct their eyes towards imaginary targets defined by extrafoveal cues. Independent of the type of target, real or imaginary, the trajectory of target movement determined the type of eye movement produced: steps in...

This paper studies non-proper negative imaginary systems. First, the concept of negative imaginary transfer functions thatmayhavepoles at the origin and infinity is introduced. Then, a generalized lemma is presented to provide a sufficient condition to characterize the non-proper negative imaginary properties of systems. The generalized lemma is given in terms of complex variable s in the quart...