Predicting the Unknown: Novelty Processing depends on Expectations.

We presented predictable series of five stimuli; the first three preceded by a cue indicating that the next stimulus was likely to be a standard stimulus, and the last two preceded by a cue indicating that the next stimulus was likely to be novel. On some trials a cue typically predicting a standard was in fact followed by an unexpected novel stimulus. This design allowed to investigate the independent effects of (violated) expectations and repetition on novelty processing. The initial detection of expected novels was enhanced compared to unexpected novels, as indexed by a larger anterior N2. In contrast, the orienting response, as reflected by a novelty P3, was reduced for expected compared to unexpected novels. Although the novel stimuli were never repeated themselves, they could be presented after one another in the sequence. Such a category repetition affected the processing of novelty, as evidenced by an enhanced anterior N2, and a reduced novelty P3 for novels preceded by other novels. Taken together the current study shows that novelty processing is influenced by expectations.
PMID: 29758180 [PubMed - as supplied by publisher]

Source: Brain Research - May 11, 2018 Category: Neurology Authors: Schomaker J, Meeter M Tags: Brain Res Source Type: research