EEG

EEG stands for electroencephalography, a technique for measuring electrical activity in the brain. By placing electrodes on the scalp, researchers and clinicians can detect the voltage fluctuations produced by neural firing patterns, revealing insight into consciousness, sleep, and neurological health.

EEG emerged in the 1920s as a revolutionary window into the living brain. It remains invaluable for diagnosing epilepsy, monitoring anesthesia, and studying conditions like depression and autism. The recorded signals—typically oscillating between 1 and 100 hertz—are organized into frequency bands (delta, theta, alpha, beta, gamma) that correlate with different mental states and cognitive function.

Modern EEG systems can track dozens of electrodes simultaneously, often combined with computational analysis and machine learning to detect subtle patterns. Brain-computer interfaces use EEG signals to let paralyzed patients control prosthetics or communicate. Despite competition from fMRI and other neuroimaging methods, EEG remains popular: it's portable, affordable, and offers millisecond-level temporal resolution.

The field continues evolving—wireless headsets, dry electrodes, and open-source software tools are democratizing access to neuroscience.

Related

Neuroscience, Neuroimaging, Brain activity, Sleep stages, Seizure detection, Neurotechnology