Timing predictability enhances regularity encoding in the human subcortical auditory pathway

Abstract

The encoding of temporal regularities is a critical property of the auditory system, as short-term neural representations of environmental statistics serve to auditory object formation and detection of potentially relevant novel stimuli. A putative neural mechanism underlying regularity encoding is repetition suppression, the reduction of neural activity to repeated stimulation. Although repetitive stimulation per se has shown to reduce auditory neural activity in animal cortical and subcortical levels and in the human cerebral cortex, other factors such as timing may influence the encoding of statistical regularities. This study was set out to investigate whether temporal predictability in the ongoing auditory input modulates repetition suppression in subcortical stages of the auditory processing hierarchy. Human auditory frequency–following responses (FFR) were recorded to a repeating consonant–vowel stimuli (/wa/) delivered in temporally predictable and unpredictable conditions. FFR amplitude was attenuated by repetition independently of temporal predictability, yet we observed an accentuated suppression when the incoming stimulation was temporally predictable. These findings support the view that regularity encoding spans across the auditory hierarchy and point to temporal predictability as a modulatory factor of regularity encoding in early stages of the auditory pathway.

When temporal prediction errs: ERP responses to delayed action-feedback onset

“…When expected self-generated sensory feedback is modified, suppression is reduced (e.g., Knolle et al, 2013b). Differences in the processing of self-generated and externally generated input have also been observed in middle latency responses preceding the N1 (i. e., approximately at 27-33 ms after sound onset; Baess et al, 2009), which are sensitive to the temporal regularity of a stimulus (Gorina-Careta et al, 2016;Leung et al, 2013). The P50 (even though not directly examined in the context of button press tasks) was also found to be sensitive to temporal stimulus predictability White and Yee, 2006).…”

Hidden Markov modeling of frequency-following responses to Mandarin lexical tones

“…These experiences include long-term language experience (Krishnan, Xu, Gandour, & Cariani, 2005; Krizman, Marian, Shook, Skoe, & Kraus, 2012; Krizman, Skoe, Marian, & Kraus, 2014; Xie, Reetzke, & Chandrasekaran, 2017), musical training (Musacchia, Sams, Skoe, & Kraus, 2007; Wong, Skoe, Russo, Dees, & Kraus, 2007), short-term auditory training (Song, Skoe, Wong, & Kraus, 2008; Xie et al, 2017), online context (Lau, Wong & Chandrasekaran, 2016), and stimulus probability and FFR timing (Gorina-Careta, Zarnowiec, Costa-Faidella & Escera, 2016; Shiga, Althen, Cornella, Zarnowiec, Yabe & Escera, 2015; Slabu, Grimm & Escera, 2012). Following this line of research, recent studies have documented a more faithful subcortical encoding of lexical tones (e.g., Mandarin tones) in native speakers of tonal languages (e.g., Chinese), relative to native speakers of languages that are not tonal (e.g., English) (Krishnan et al, 2010; Krishnan, Gandour, Bidelman, & Swaminathan, 2009; Krishnan et al, 2005; Xie et al, 2017).…”

Monkeys share the neurophysiological basis for encoding sound periodicities captured by the frequency-following response with humans

“…More recently, it has been shown that the FFR can also act as a diagnostic tool for mild traumatic brain injuries 18 , 19 . Importantly, the FFR exhibits flexibility at different time scales and can be modified by changes in the stimulus dynamics 20 – 22 and by short 23 – 25 and long-term experiences 26 , 27 . Short-term interventions, such as auditory or linguistic training, enhance the neural encoding of the F0 which accompanies improvements in perceptual skills 25 , 28 .…”