Measuring Brain Activity

A non-invasive technique that measures the electrical activity (brain waves) generated by large populations of neurons in the brain, recorded from electrodes placed on the scalp. EEG offers excellent temporal resolution (milliseconds), making it ideal for studying the timing of cognitive processes, but its spatial resolution is poor.

A non-invasive technique that measures the magnetic fields produced by the electrical currents generated by neuronal activity. MEG offers excellent temporal resolution (milliseconds) and better spatial resolution than EEG, making it valuable for studying dynamic brain function, often used in conjunction with fMRI.

A non-invasive neuroimaging technique that measures brain activity by detecting changes in blood oxygenation and flow (BOLD signal) in response to neural activity. fMRI offers good spatial resolution (millimeters), allowing localization of function, but its temporal resolution is relatively poor (seconds).

An invasive technique that uses a microelectrode inserted into the brain to measure the electrical activity (action potentials) of individual neurons. This method provides the highest spatial and temporal resolution (single cell, milliseconds) to understand how specific neurons encode information.