Irrelevant Predictions: Distractor Rhythmicity Modulates Neural Encoding in Auditory Cortex

Abstract

Dynamic Attending Theory suggests that predicting the timing of upcoming sounds can assist in focusing attention towards them. However, whether similar predictive processes are also applied to background noises and assist in guiding attention away from potential distractors, remains an open question.Here we address this question by manipulating the temporal predictability of distractor sounds in a dichotic listening selective attention task. We tested the influence of distractors' temporal predictability on performance and on the neural encoding of sounds, by comparing the effects of Rhythmic vs. Nonrhythmic distractors. Using Magnetoencephalography (MEG) we found that, indeed, the neural responses to both attended and distractor sounds were affected by distractors' rhythmicity. Baseline activity preceding the onset of Rhythmic distractor sounds was enhanced relative to Non-rhythmic distractor sounds, and sensory response were suppressed. Moreover, when distractors were Rhythmic, responses to attended sounds were more strongly lateralized to the contra-lateral hemisphere. Behavioral performance also improved in the Rhythmic condition. These combined behavioral and neural results suggest that not only are temporal predictions formed for task-irrelevant sounds, but that these predictions bear functional significance for promoting selective attention and reducing distractibility.

Linguistic processing of task-irrelevant speech at a cocktail party

“…Additional brain regions, such as the PPC, are also engaged in representing some aspects of the linguistic structure of task-irrelevant speech, which we interpret as maintaining a representation of what goes on in the 'rest of the environment', in case something important arises. Importantly, similar interactions between the structure of task-irrelevant sounds and responses to the to-be-attended sounds have been previously demonstrated for non-verbal stimuli as well (Makov and Zion Golumbic 2020).…”

Linguistic processing of task-irrelevant speech at a Cocktail Party

“…Additional brain regions, such as the PPC, are also engaged in representing some aspects of the linguistic structure of task-irrelevant speech, which we interpret as maintaining a representation of what goes on in the ‘rest of the environment’, in case something important arises. Importantly, similar interactions between the structure of task-irrelevant sounds and responses to the to-be-attended sounds have been previously demonstrated for non-verbal stimuli as well (Makov and Zion Golumbic 2020). Together, this highlights the fact that attentional selection is not an all-or-none processes, but rather is a dynamic process of balancing the resources allocated to competing input, which is highly affected by the specific perceptual, cognitive and environmental aspects of a given task.…”

Sustained Pupil Responses Are Modulated by Predictability of Auditory Sequences

“…On the other hand, a large body of work demonstrates that the brain exhibits reduced responses to regular, predictable stimuli (de Lange et al, 2018;Itti and Baldi, 2009;Richter et al, 2018), interpreted as reflecting the fact that the detection of regular structure facilitates the conservation of processing and computational resources. Indeed, it has been shown that regular patterns are easier to process (Rohenkohl et al, 2012) and also, critically, easier to ignore (Andreou et al, 2011;Southwell et al, 2017;Makov and Zion Golumbic, 2020) which has been taken as evidence that regularity does not draw on attentional resources.…”