The aim of this paper is to show that the fast information-communication, coupled with technological development, has created a high degree of dependence on financial and other markets. Such dependence in times of general economic growth through transmission channels had a huge impact on the stability of financial markets, respectively to global economic prosperity. However, with the onset of the mortgage crisis, the transmission channels erupted to the fore and, above all, the stock market channel, which has played a key role in the speed and transfer of instability from one to the other markets. This is why its irreplaceable role in the functioning of modern market. Stock exchange channel we observed through the stock exchange indices, which represent an important indicator of financial market development, but also the economy as a whole. The paper uses the method of generalization observation average of stock market indices. As global underdeveloped stock markets have the greatest impact on the transmission of the crisis in an unstable period, so in this article we look at the stock indices elected representative markets such as: America, China and the European Union. Results of testing this interactive market largely allow us to come to the conclusion what impact the stock markets have on transmission of instability in the crisis period.