Abstract: Recently, more sensitive imaging methods for identification of alterations in brain function have been developed. Since, a varieties of imaging modalities are available, it is possible that multiple capabilities of the various kinds of radiation are used in our practice. The positron emission tomography (PET) and functional magnetic resonance imaging (fMRI) are the commonly used and most promising molecular imaging methods for the identification of alterations in brain functioning. In view of the difficulties noted during developing the specific contrast agents for MRI, methods for fMRI use was identified and therefore the success of fMRI is mainly because of the presence of an endogenous contrast agent in human body which has been found to have high sensitivity. Interestingly, fMRI can provide exceptional features which increase its performance; including utility and necessity.The blood of adults contains about 750g of hemoglobin that is rich in iron, which cannot be achieved in any endogenous agent that can act as contrast. The iron in deoxy- hemoglobin acts as a contrast agent in the fMRI technique. In presence of oxidation, hemoglobin may loose its contrast enhancing nature. In the deoxygenated hemoglobin, the deoxyhemoglobin/oxyhemoglobin ratio defines the intensity of signals because iron is paramagnetic due to its four unpaired electrons. It is similar to gadolinium in the common MRI contrast agents. The neural activity as well as spiking of neurons, can occur due to rise in the uptake of glutamate in astrocytes which may be under influence of blood oxygen level dependent effect. In the high performance of fMRI, many features contribute to clearance of physiopathology via physiological imaging of neurons as given in Table 1. There are several neuro-psychiatric dysfunctions and cardiovascular diseases (CVDs) in which brain imaging has been used to correlate and mental diseases with images of brain areas such as in schizophrenia, depression, anxiety disorders etc. The amygdalar activity which is known to transform stressful events into anxiety and fear extinction, have also been studied via fMRI which may be used as new targets for advances in therapy .
Table 1: Special features for better performance of fMRI.

Biography: Prof. Ram B Singh is an international expert in Neuro-Cardiology, Chronobiology and Nutraceuticals, antioxidants (Regenerative Medicine). Stanford Univ. List 2020, One of Top Four CVD Scientist of India and out of 1000 top CVDS scientists in the world.
1.Editor, World Heart Journal, www.novapublishers.com (USA) and
2.Hon. Fellow, Halberg Chronobiology Centre, University of Minnesota, Minneapolis, USA.
3.(Contributed > 550 research papers in peer reviewed journals),16,510, Citations; https://scholar.google.co.in/citations?hl=en&view_op=list_works&gmla=AJsN-F5_LOEW7U3xbWEQocYuoSbdb02vXMP-eDVQpPWl2
4. Written and edited 7 text books, American publishers, Elsevier, nova science, NY, USA,Most Classical, Functional Food Security in Global health, Elsevier, USA,2018.
5.Received 12 International awards including Dr Zumkley Memorial award; US$1500.00,
6.Fellow of the International Academy of Cardiovascular Sciences, Winnepeg, Canada, 2014,
7.Dr NS Dhalla Falecitation Lecture of the International College of Cardiology, Recife, Brazil, 2015.
Golden Shield from Chief Executive of Charter, Department of Health, UAE, for lifetime achievements in CVDs, 2015,
8.President, Tsim Tsoum Institute, Krakow, Poland. Member, Russian Academy of Medical Sciences,,Former President & Founder, Indian Society of Hypertension, International College of Cardiology and International College of Nutrition.,
9.Designed and supervised several experiments on animal models of athero-thrombosis.
10.President, Indian Society of Chronomedicine 2017-2018.