Saint Petersburg scientists collaborate with their American colleagues to find out biological bases of psychological dependency from alcohol, drugs and other substances.
      
      Syndrome of psychological dependency involves emotions, memory and motivation, as well as person’s character, temper, hereditary, social and other factors.
      
      Most important physiological factor is related to neurons, which use neurotransmitter dopamine for neural signal transmission – such mechanism is called brain-reinforcing system. This system functions under both natural reinforcing stimuli – food, sex and creation process – and artificial pleasure stimuli.
      
      Scientists have divided factors, which stimulate one to take mentioned substances, into three groups – the first group includes availability and cost of a substance. The second one combines human characteristics – age, gender, ethnic patterns, genetic predisposition, previous diseases, character and temper. The third one consists of social factors – care defects, family atmosphere, bad living conditions and lack of attention from state authorities.
      
      The more factors are considered, the more accurate predictions of psychological dependency can be made.
      
      Source: Science News