Dementia affects about 8% of people age 65 years and older. Identification of dementia is particularly difficult in its early phases when family members and physicians often incorrectly attribute the patient's symptoms to normal aging. The most frequently occurring ailments that are connected with neurodegeneration are: Alzheimer's disease, Parkinson's disease, Huntington's disease, amyotrophic lateral sclerosis, and multiple sclerosis. A variety of powerful techniques that have allowed visualization of organ structure and function with exact detail have been introduced in the last twenty-five years. One such neuroimaging technique is positron emission tomography (PET), which measures in detail the functioning of distinct areas of the human brain and as a result plays a critical role in clinical and research applications. Radiotracer-based functional imaging provides a sensitive means of recognizing and characterizing the regional changes in brain metabolism and receptor binding associated with cognitive disorders. The next functional imaging technique widely used in the diagnosis of cognitive disorders is single photon emission computed tomography (SPECT). New radiotracers are being developed and promise to expand further the list of indications for PET. Prospects for developing new tracers for imaging other organ diseases also appear to be very promising. In this review, we present current opportunities of neuroimaging techniques in the diagnosis and differentiation of neurodegenerative disorders.