Oddball paradigm

The oddball paradigm has a wide selection of stimulus types, including stimuli such as sound duration, frequency, intensity, phonetic features, complex music, or speech sequences.

In the classic Oddball paradigm, two types of stimuli affecting the same sensory channel are presented randomly within an experiment, with a significant difference in the probability of occurrence.

These novel stimuli are likely to provoke an orienting response in subjects and can trigger the P3a component, making this paradigm essential for studying involuntary attention.

[2] In ERP research it has been found that an event-related potential across the parieto-central area of the skull that usually occurs around 300 ms after stimuli presentation called P300 is larger after the target stimulus.

[5] Since P300 has been shown to be an attention-dependent cognitive component in wakefulness, one might suppose that it would be absent during sleep; a time in which information processing of external stimuli is commonly thought to be inhibited.

[7] The classic auditory oddball paradigm can be modified to produce different neural responses and can therefore be used to investigate dysfunctions in sensory and cognitive processing in clinical samples.

[8] A unique application of the oddball paradigm is being used heavily in Schizophrenia research to study the effects in neuronal generator patterns in continuous recognition memory, and the endophenotypes, which provide model on genetic relation of psychiatric diseases that represents phenotypes between manifest clinical syndrome and genetic underpinnings.

The oddball paradigm has robust effects on pupil dilation that is produced by transient activity of the subcortical locus coeruleus.

For example, in a still-face procedure, the mother suddenly adopts a neutral facial expression and stops responding to the infant's contingencies.

By monitoring responses such as surprise reactions, crying or distress, suppressed motor activity, duration of gaze, amplitude and latency of brainwave components, and changes in heart rate, researchers can learn which stimuli are out of the ordinary for infants.

In the classical oddball paradigm, if participants are asked to respond to a deviant stimulus, the deviant stimulus is the target stimulus at that point.
The P300 response of different healthy subjects in a two-tone auditory oddball paradigm. The plots show the average response to oddball (red) and standard (blue) trials and their difference (black). From Surprise response as a probe for compressed memory states . [ 3 ] These examples show the significant individual variability in amplitude, latency and waveform shape across different subjects.