Why do steroids cause aggressiveness?

As you know, steroids are taken by numerous athletes in order to enhance muscle mass and strength. But according to late studies, taking of steroids is a very harmful factor for brain cells. Since these preparations induce amount of testosterone in body, they affect and even destroy brain cells. This confirmation about destruction of brain cells by induced amount of testosterone was proven by a study conducted by Yale School of Medicine that was published in the Journal of Biological Chemistry.
Scientists confirm that unusual aggressiveness manifested by steroids users show that certain amount of nerve cells was destroyed due to utilizing of steroids.
Barbara Ehrlich, a professor, a leader of a study related to steroids use, recommends not to condemn those who apply steroids, when they act aggressively. You must understand that it can be not their fault. Steroids must have had fault of aggressiveness of those who administrate these medicines.
The research leaded by Yale School of Medicine displayed that testosterone destroyed nerve cells. One of main functions of testosterone produced naturally is following: to destruct brain cells that may be harmful for the whole body due to their damages. But when level of testosterone is increased, it destroys not only destructed cells but healthy ones too. It may lead to such dangerous problems, as appearing of Alzheimer's and Huntingdon's disease and others.

Aggressiveness of hamsters due to steroids
Hamsters were recruited in one of studies published in the journal Behavioral Neuroscience. The scientists involved in the study observed effects of anabolic steroids upon the hamsters. The hamsters that were given these drugs became too aggressive. Their brain activity was modified a lot due to steroids.
The researches made a conclusion that steroids damaged people’s brain the same way as hamsters’ brain. According to their confirmations, people suggest that steroids are forbidden due to their athletic effects. But they must realize that the chief reason is harmful influence of these medications upon human health. Steroids must be administrated only for treatment of diseases by prescriptions of pharmacists. Steroids use in sports should be avoided totally.