Explain the term - Neurochemical Manipulations

Neurochemical and immunological methods have been used to identify groups of neurons in the central nervous system that use specific neurotransmitters. The number of neurotransmitters identified continues to increase, and one neuronmay express more than one neurotransmitter. The anatomy of major neurotransmitter pathways has been elucidated, and the molecular mechanisms by which some neurotransmitters function is now known in some detail. Drugs given systematically or applied to specific anatomic areas may stimulate or block specific neurotransmitter receptors. There are also drugs that will selectively destroy neurons containing specific neurotransmitters, and genetic methods are available to produce animals that lack specific enzymes. Through PET studies, specific neurotransmitters such as dopamine can be imaged in humans. Using these and other techniques, it is possible to correlate the behavioural effects of pharmacological agents with dysfunction in anatomical areas defined by chemical criteria.