Last two decades has been the era of emerging technologies which provide rapid and high accurate methods in the field of neuroscience. The brain is one of the most unique systems, whose functions are still being a mystery. The uppermost region in the brain is called cerebrum which is divided into two hemispheres with a central fissure separating them. Both the cerebral hemispheres act as information receiving and sharing regions obtained from sense organs, along with controlling of entire body functions. The two hemispheres have distinct functions where one half controls speech, reading, learning, emotions, muscle functions and thought process. The function of both hemispheres is so distinct that the right hemisphere controls all functions of muscles and an organ on the left side of the body and the left hemispheres takes care of the right side. Advancement in brain imaging methods has been booming in recent times allowing us to determine the structure linked to function, physical, physiological features of the brain, developmental stages etc. Information obtained from such methods provide easier data pre processing, create novel analytical models and improve the sensitivity of detection. Technologies available in the present era to understand the cerebral hemispheres of the brain are Magnetic Resonance Imaging (MRI), functional Magnetic Resonance Imaging (fMRI), Positron Emission Tomography (PET), Electroencephalography (EEG), Near Magnetoemce phalogram (MEG), and Near-Infrared Spectroscopy (NIRS).

Magnetic Resonance Imagining (MRI): It provides visualization of grey matter, white matter and brain tissues. This differentiation is possible as the water and fat content in grey and white matter is distinct in having a different magnetic field. White matter has axons which perform functions like transmission of electrical signals between neurons, myelin sheaths. White matter has higher fat content which provides insulation to axons. The technique Voxel-based morphometric allows quantitative measurement of white/grey matter, determining the shape, size across the tissue. The key advantage of MRI is that it is a non-invasive process providing complete anatomical information of the brain rapidly. MRI scanning devices are expensive and any motion arte facts during detection can lead to disrupted image processing. Histological Analysis of the brain can be done when the brain cells are exposed to a specific type of agent which binds to the particular structure of interest. This method is only used for in vivo experimental animal models like rats, mice, rabbits, macaque monkeys etc. The agent which targets particular loci of the brain is injected into the brain, this agent gets transported along with axons for a particular period of time. The tissue obtained from the sacrificed brain undergoes image processing under light microscopy or electron microscopy. Agents used in such technique are fluorescent in nature. The technique is used as the gold standard in understanding brain functions and significance of specific regions of the brain through image processing. This method is not much implemented using apes and humans.

Last two decades has been the era of emerging technologies which provide rapid and high accurate methods in the field of neuroscience. The brain is one of the most unique systems, whose functions are still being a mystery. The uppermost region in the brain is called cerebrum which is divided into two hemispheres with a central fissure separating them. Both the cerebral hemispheres act as information receiving and sharing regions obtained from sense organs, along with controlling of entire body functions. The two hemispheres have distinct functions where one half controls speech, reading, learning, emotions, muscle functions and thought process. The function of both hemispheres is so distinct that the right hemisphere controls all functions of muscles and an organ on the left side of the body and the left hemispheres takes care of the right side. Advancement in brain imaging methods has been booming in recent times allowing us to determine the structure linked to function, physical, physiological features of the brain, developmental stages etc. Information obtained from such methods provide easier data pre processing, create novel analytical models and improve the sensitivity of detection. Technologies available in the present era to understand the cerebral hemispheres of the brain are Magnetic Resonance Imaging (MRI), functional Magnetic Resonance Imaging (fMRI), Positron Emission Tomography (PET), Electroencephalography (EEG), Near Magnetoemce phalogram (MEG), and Near-Infrared Spectroscopy (NIRS).

Magnetic Resonance Imagining (MRI): It provides visualization of grey matter, white matter and brain tissues. This differentiation is possible as the water and fat content in grey and white matter is distinct in having a different magnetic field. White matter has axons which perform functions like transmission of electrical signals between neurons, myelin sheaths. White matter has higher fat content which provides insulation to axons. The technique Voxel-based morphometric allows quantitative measurement of white/grey matter, determining the shape, size across the tissue. The key advantage of MRI is that it is a non-invasive process providing complete anatomical information of the brain rapidly. MRI scanning devices are expensive and any motion arte facts during detection can lead to disrupted image processing. Histological Analysis of the brain can be done when the brain cells are exposed to a specific type of agent which binds to the particular structure of interest. This method is only used for in vivo experimental animal models like rats, mice, rabbits, macaque monkeys etc. The agent which targets particular loci of the brain is injected into the brain, this agent gets transported along with axons for a particular period of time. The tissue obtained from the sacrificed brain undergoes image processing under light microscopy or electron microscopy. Agents used in such technique are fluorescent in nature. The technique is used as the gold standard in understanding brain functions and significance of specific regions of the brain through image processing. This method is not much implemented using apes and humans.

Methods to study brain function:
Functional Magnetic Resonance Imaging (fMRI): This method determines the physiological conditions using MRI, the key function is to identify areas in the brain which have increased blood flow during a specific physiological function. The principle depends on the ability of oxygenated haemoglobin being absorbed by MRI signals, and deoxygenated blood does not get absorbed. The technique has a higher resolution to determine spatial and temporal regions than PET. The key disadvantage of this technique is that the measurement accuracy depends on the physical activity performed by the subject under observation.

Fluorodeoxyglucose (FDG): In this method, radio-labelled glucose with 18F with a half-life of 110 minutes is used. This technique helps in mapping the neural activation procedure by relying on glucose metabolism. This process involves giving a specific dose of FDG to the subject intravenous or orally and then determine the behaviour tracking. This FDG is taken up by the neurons where the 18F is trapped inside the cells, during the decay process of 18F positrons are released, when electrons released by the instrument are kept close to the subject two photons are released. The scanner captures these photons and thereby provide processed image based on it. The region with increased brightness represents increased glucose metabolism. Glucose metabolism acts as an indicator of neural activity.

H152 O-PET: It is a technique which helps in determining the neural activation procedure using blood oxygenation. Similar to FDG, PET H152 O-PET detects specific protons released after radioactive decay. 15O has a half-life of 2 minutes, the radio labelled molecule is injected and continuous image processing is done. Any region showing higher brightness determine higher blood flow rate representing the neural activation procedure. This method has high resolution in comparison with FDG-PET and is a non-invasive method.

Electroencephalography (EEG): This technique uses the method of determining voltage fluctuations occurring in the brain using tiny electrodes attached to the scalp. The voltage fluctuations are captured and are stored for every specific physical activity performed by the subject. This technique has a greater temporal resolution in comparison with fMRI and PET.

Magnetoencephalography (MEG): This method depends on capturing of the magnetic field generated inside the brain, this method is different from EEG only in the process of capturing the magnetic field instead of electric signals. MEG is sensitive in determining the neural activity specifically originated from the cortical region present perpendicular to the scalp region. This has a higher temporal resolution than EEG.