Event-related potentials (ERPs) are electrical voltage changes that occur in the brain in response to specific stimuli or events. These changes are measured by placing electrodes on the scalp and recording the electrical activity of the brain, known as the electroencephalogram (EEG).
ERPs reflect the brain's processing and response to various sensory, cognitive, or motor events. They are highly time-locked to the occurrence of a particular event and are known for their high temporal resolution. This means they can precisely capture the brain's immediate neural activity following the presentation of a stimulus.
Generally, ERPs are characterized by specific components or waves that occur at different time points after stimulus onset. These components are denoted by a letter or a combination of letters, such as N (negative) or P (positive), followed by a number representing the component's latency in milliseconds.
By comparing and contrasting ERPs across different conditions or groups, researchers can gain insights into cognitive processes such as attention, perception, memory, language, emotion, and information processing. ERPs are widely used in neuroscience and psychology research to investigate neural mechanisms underlying various mental functions and disorders.
In summary, event-related potentials are electrophysiological responses recorded from the scalp that reflect the brain's activity in response to specific stimuli or events. These responses provide valuable information about the brain's processing and can help elucidate the cognitive processes involved in human perception, attention, and cognition.