<p>In this review, we have aimed at presenting the functions and function disorders of dopaminergic and serotoninergic pathways in the brain, leading to neurodegeneration. Based on the existing literature data, we discussed the common functioning of dopamine and serotonin neurotransmitters, as well as their contribution to the unique actions in psychophysiological aspect. The dopaminergic and serotoninergic pathways and the receptor classes for dopamine and serotonin were presented, in accordance to the latest literature. Besides their separate action, we discussed their interconnections as well. The interaction of dopaminergic and serotoninergic pathways was presented and the effect of the alteration of one neurotransmitter concentration on another functioning was discussed. The neurodegeneration overview was given as a&#xa0;death of the specific group of neurons and the specific diseases that have connection to dopamine and serotonin transmission disorders were described. Here were also issued the concentration differences of dopamine and serotonin in the periphery and brain, respectively, which result from the brain-blood barrier. The literature data insisted on the more pronounced concentration difference for dopamine, while for serotonin the concentrations in opposite sides of the brain-blood barrier are almost the same. Nevertheless, dopamine concentrations in the opposite sides of the brain-blood barrier correlate with each other. It was concluded that because of the vital importance of both dopamine and serotonin in human organism their concentration should be monitored. The perspectives to predict the possible alterations in neurotransmitter concentrations were discussed.</p>