By way of closing this brief account of our understanding of the current conception of the memory system as viewed by cognitive psychologists (Greeno and Bjork, 1973; Lindsay and Norman, 1972), we see that the control processes taking place in STM act to unite structural information from the SIS with such information retrieved from LTM. Thus, the control processes (attention) deal with information coming from outside and within the person. When these control processes are brought to bear on auditory information in SIS, the listening process is defined; when performed on visual information in SIS, the looking process is defined. From this perspective then, it is clear that to better understand the nature of listening and looking, we must have a better understanding of the processes of attention occurring in STM.
The nature of the environmental display, the sense organs, and the neural mechanisms responsible for the internal representation (perception) of environmental information are, of course, different in looking and listening. However, beyond these display and physiological differences, the looking and listening processes are quite similar; both processes entail attention-the active selection of information from the environment for storage in SIS and its subsequent manipulation in STM to meet some cognitive requirement.
E. Gibson (1969) has identified certain developmental changes which occur in the attentional processes from childhood to adulthood: