Brain Imaging

The brain is one of the body’s vital organs and is responsible for the conduction and coordination of various body tasks. The brain structure is quite complicated and divided into various hemispheres. The brain consists of millions of neurons. The detection of damage to any part of the brain or studying the brain diseases requires imaging of the brain. Various brain imaging techniques like EEG, PET, and MRI are used to obtain these images. All these methods of imaging differ from each other. Let’s study them.

Human Brain

The brain is the central organ system of the nervous system in humans. The major components of the brain include the brain stem, the cerebrum, and the cerebellum. 

The cerebrum is the largest part of the brain. The brain is divided into two hemispheres: the left hemisphere and the right hemisphere.The brain’s left hemisphere is responsible for logical thinking, while the right hemisphere is responsible for creative thinking. The brain consists of many complicated organs such as the midbrain, pineal body, medulla oblongata, pons Varolli, corpus callosum, the body of fornix, etc.To accurately map the brain’s structure and identify and study the various disorders of the brain, brain imaging techniques need to be used. Let us study various brain imaging techniques.

Brain imaging techniques

Brain imaging, alternatively called urine making, is the quantitative study of the structure and function of the central nervous system. It helps to study the human brain known invasively as to what the two broad categories of brain imaging techniques are as given below.

• Structural imaging: 

Such brain imaging techniques are used to study the structure of the brain.

• Functional brain imaging:

Functional brain imaging techniques are used to study brain function using fMRI and pet scan techniques.

Following are a few types of brain imaging techniques.

Diffuse optical imaging

The diffuse tickle imaging technique uses near-infrared light to generate images of the body. The optical absorption of haemoglobin is measured, and this technique realises the absorption spectrum of haemoglobin in its oxygenation status. The HD-DOT type of optical imaging can be compared with the fMRI imaging technique.

Magnetic Resonance Imaging

The magnetic resonance imaging technique is popularly known as MRI scan. The MRI technique makes use of radio waves and magnetic fields to produce high-quality 2D or 3D images of the brain without making use of radioactive resources or X-rays.The highest spatial resolution image of the brain ever produced with MRI was up to 100 microns.

Functional magnetic resonance imaging

It is also known as fMRI. This brain imaging technique uses paramagnetic properties of deoxygenated and oxygenated haemoglobin to trace images of changing blood flow in the brain, which is associated with neural activities in the brain. The subjects of the fMRI test are shown different visual images, touch, and sound stimuli and are asked to perform various actions like pressing buttons. FMRI maps the brain images during these activities.

Magnetoencephalography

This brainy machine technique is popularly known as MEG. The electric activities in the brain produce magnetic fields, and the MEG technique measures them. The neural electric activity is directly measured with MEG as compared to fMRI. The temporal resolution obtained is high; however, the spatial resolution obtained is low. The advantage of MEG is that the measurement is not much likely to be distorted by surrounding tissue in the skull and scalp, unlike in EEG. The uses of MEG include assisting the surgeons in localising a pathology and helping the researchers in the determination of functions of various parts of the brain.

Functional ultrasound imaging

Functional ultrasound imaging is a brain imaging technique in which ultrasound imaging is used to measure and detect changes in neural activities or metabolism. The functional ultrasound emission depends on ultrasensitive doppler and ultrafast ultrasound imaging, making high-sensitivity blood flow imaging possible.

Photon emission tomography

The photon emission tomography is popularly known as PET scan. PET scan measures the emissions from radioactively labelled metabolically active chemicals injected into the bloodstream. The computer then processes the data to produce 2D and 3D images of the distribution of chemicals in the brain.

Such are the various types of brain imaging techniques.

Conclusion

The brain is a complex organ and is made up of many small and complicated parts. Studying the structure of the brain’s functioning can be easily done by studying the brain images obtained using brain imaging techniques. Brain imaging is mostly of two types, structural imaging, and functional imaging. The popular techniques include Magnetic resonance imaging (MRI), computed tomography, CT scan, Positron Emission Tomography, PET scan, etc. The fMRI is list invasive and possesses less risk; hence it is very popular.