Rapid growth of cities and towns, use of new building materials, aesthetic position of specialists, whose viewpoints were based on industrial methods of building, and necessity of fighting against "architectural extravagances" have led to sharp deterioration of visual environment. The set of visual details composed the environment was gradually decreased, and now it is consists of two main components just as straight lines and right angles. Colour scale in most cities and towns also is rather poor. As a rule it contains two or three colours only. At the same time there are many great planes and still objects in urban environment. These facts have led to sharp difference between urban visual environment and the natural one, where a human being has occurred as biological species.

Videoecology is a field of knowledge about interaction of a human being and visual environment.The videoecology is based on the concept of saccade automation (V.A.Filin, 1987). According this concept fast eye motions (saccades) arise in accordance with principles of automation. Outside visual stimuluses can modulate parameters of saccades.

Homogeneous visual fields are these ones where visual elements are not available at all or their number is sharply reduced. In urban conditions homogeneous visual fields are generated by bare walls, fences, roofs, asphalt surfaces of roads etc. The use of great planes and large glasses, films, linoleum, plastics create homogeneous visual environment. An eye can not work properly in such surroundings because there are nothing to catch on after the next saccade, and as a result saccade amplitude sharply increases. It means that the eye works not in economic mode and a person feels a discomfort.

Aggressive visual fields are these ones where a lot of identical visual details is evenly disturbed on some surface. For example multi-storey building with great number of windows creates aggressive visual field (many identical visual elements). An eye can not determine the very window it is looking at, as all the windows are similar. There is nothing of the kind in natural environment: as a rule an eye "knows" for sure where it is looking at and what the element it is fixing now. Tiled walls, nets, lattices, corrugated aluminium, roofing slate, striped panels, brick walls, sidewalks paved with square tiles increase the quantity of aggressive fields in urban environment.

Social consequences. Any violation of living environment results in negative consequences. In particular the specialists know well, that the process of urbanisation leads to steady rise of the number of psychic diseases. We can say that unfavourable visual environment is one of the factors increasing the number of mental patients. In our opinion the quantity of myopic patients in cities is more than in country because urban visual environment is worse than country visual environment. Besides above-mentioned facts we believe that aggressive visual environment forces a person to aggressive actions. The rise of the number of aggressive visual fields makes the crime situation worse.