ABSTRACT
The processes involved in visual perception enable us to act and react to the visual environment safely and accurately. We need to know what things are and where things are, and where we are in relation to them. The problem for visual perception is to make sense of the sensory data that is detected as patterns of light falling on the retina. The retina is a two-dimensional, flat surface, yet we perceive the world in three dimensions: how is this achieved? Some perceptual processing is a direct outcome of the biological and physiological nature of the visual system, whereas other perceptual processes involve the use of knowledge gained from experience with the visual world. Together with attentional and memory processes, perceptual processing gives rise to our experience of the visual objects and events around us. Although we are only concerned with vision in this chapter, it is important to remember that many objects in the environment have perceptual properties from other modalities, in that they possess auditory, tactile and other sensory properties as well. In later chapters we shall examine hearing and touch and cross-modal effects in perception. So, another problem for perception is to combine information about the properties of objects and the environment.
