- The EEG (electroencephalography) is a remarkable tool in physics and neurobiology that offers a non-invasive window into the human brain, celebrating its centenary since the first human EEG was produced.
- This innovation, attributed to German physiologist Hans Berger in 1924, was preceded by significant advances in Europe.
- EEG works by measuring electrical activity in the brain generated by neurons.
- Health workers place electrodes on the scalp, which detect voltage changes caused by ion movement in neurons.
| 10-20 System In this system, the distance between two adjacent electrodes is either 10% or 20% of the total distance between two points on the head along which electrodes are being placed. |
- These electrodes send data to a computer, creating an electroencephalogram.
- The raw data collected must be corrected for volume conduction and noise before interpretation.
- Volume conduction refers to the movement of electrical activity through the brain’s three-dimensional volume before reaching the electrodes.
- The International 10-20 System ensures standard placement of electrodes.
- EEG is widely used in reference standards for diagnosing epilepsy.
- It also monitors the effects of anaesthesia, sleep patterns, neurological activity during a coma, and oxygen availability.
- Additionally, EEG can confirm brain death, one of the two legally recognized forms of death in India.
- EEG has several advantages, including tracking rapid brain activity in milliseconds and being a cost-effective, simple, and non-invasive diagnostic tool.
- It does not emit high-energy radiation or confine patients to small spaces like MRI. However, it is biased toward signals near the brain’s surface and may be less effective for deeper signals.
- Researchers often use EEG in conjunction with other tests, like MRI, and employ advanced data processing methods to overcome these limitations.
Dig Deeper: Read about Neurons and their functions.
