Perceptual discrimination precision falls as stimulus variance rises

Evidence

Another possibility is that confusion between within-pattern intervals and between-pattern transpositions may make individual patterns less distinctive, and so increase the task difficulty. Therefore, we also investigated the effects of transposition size and interactions between transposition size and within-phase intervals. Finally, the predictive coding account of perception (Friston 2005 ) suggests that the precision with which perceptual discriminations can be made is inversely related to stimulus variance, suggesting that task difficulty would increase with variance of standard phrase pitch intervals. — Dijk, Pim van, Physiology, Psychoacoustics and…, 5269

Categorization

• XREF: The predictive coding/precision-varariance link is central to Friston’s free-energy framework; relevant given the reader’s stated interest in perception and cognition. — connects to: Trained panels can bypass consensus vocabulary because perception varies less than description; Electrode pairs are judged discriminable only when performance exceeds chance; Psychometric functions require prior knowledge of useful stimulus levels (+1 more)
• QUESTION: How strictly does the inverse precision-variance relation hold empirically for pitch discriminations vs. other modalities?
• corroborated: 2 independent passages support this claim — Dijk, Pim van, Physiology, Psychoacoustics and…, 5269