The Strength of the Medial Olivocochlear Reflex in Chinchillas Is Associated With Delayed Response Performance in a Visual Discrimination Task With Vocalizations as Distractors

The ability to perceive the world is not merely a passive process but depends on sensorimotor loops and interactions that guide and actively bias our sensory systems. Understanding which and how cognitive processes participate in this active sensing is still an open question. In this context, the auditory system presents itself as an attractive model for this purpose as it features an efferent control network that projects from the cortex to subcortical nuclei and even to the sensory epithelium itself. This efferent system can regulate the cochlear amplifier sensitivity through medial olivocochlear (MOC) neurons located in the brainstem. The ability to suppress irrelevant sounds during selective attention to visual stimuli is one of the functions that have been attributed to this system. MOC neurons are also directly activated by sounds through a brainstem reflex circuit, a response linked to the ability to suppress auditory stimuli during visual attention. Human studies have suggested that MOC neurons are also recruited by other cognitive functions, such as working memory and predictability. The aim of this research was to explore whether cognitive processes related to delayed responses in a visual discrimination task were associated with MOC function. In this behavioral condition, chinchillas held their responses for more than 2.5 s after visual stimulus offset, with and without auditory distractors, and the accuracy of these responses was correlated with the magnitude of the MOC reflex. We found that the animals’ performance decreased in presence of auditory distractors and that the results observed in MOC reflex could predict this performance. The individual MOC strength correlated with behavioral performance during delayed responses with auditory distractors, but not without them. These results in chinchillas, suggest that MOC neurons are also recruited by other cognitive functions, such as working memory.

The metacognition of auditory distraction: Judgments about the effects of deviating and changing auditory distractors on cognitive performance

The duplex-mechanism account of auditory distraction has been extended to predict that people should have metacognitive awareness of the disruptive effect of auditory deviants on cognitive performance but little to no such awareness of the disruptive effect of changing-state relative to steady-state auditory distractors. To test this prediction, we assessed different types of metacognitive judgments about the disruptive effects of auditory-deviant, changing-state, and steady-state distractor sequences on serial recall. In a questionnaire, participants read about an irrelevant-speech experiment and were asked to provide metacognitive beliefs about how serial-recall performance would be affected by the different types of distractors. Another sample of participants heard the auditory distractors before predicting how their own serial-recall performance would suffer or benefit from the distractors. After participants had experienced the disruptive effects of the distractor sequences first hand, they were asked to make episodic retrospective judgments about how they thought the distractor sequences had affected their performance. The results consistently show that people are, on average, well aware of the greater disruptive effect of deviant and changing-state relative to steady-state distractors. Irrespective of condition, prospective and retrospective judgments of distraction were poor predictors of the individual susceptibility to distraction. These findings suggest that phenomena of auditory distraction cannot be categorized in two separate classes based on metacognitive awareness.

The olivocochlear reflex strength in awake chinchillas is relevant for behavioural performance during visual selective attention with auditory distractors

The auditory efferent system comprises descending projections from the cerebral cortex to subcortical nuclei, reaching the cochlear receptor through olivocochlear fibres. One of the functions attributed to this corticofugal system is to suppress irrelevant sounds during selective attention to visual stimuli. Medial olivocochlear neurons can also be activated by sounds through a brainstem reflex circuit. Whether the individual variability of this reflex is related to the cognitive capacity to suppress auditory stimuli is still controversial. Here we propose that the individual strength per animal of the olivocochlear reflex is correlated with the ability to suppress auditory distractors during visual attention in awake chinchillas. The olivocochlear reflex was elicited with a contralateral broad-band noise at ~ 60 dB and ipsilateral distortion product otoacoustic emissions were obtained at different frequencies (1–8 kHz). Fourteen chinchillas were evaluated in a behavioural protocol of visual attention with broad-band noise and chinchilla vocalizations as auditory distractors. Results show that the behavioural performance was affected by both distractors and that the magnitudes of the olivocochlear reflex evaluated at multiple frequencies were relevant for behavioural performance during visual discrimination with auditory distractors. These results stress the ecological relevance of the olivocochlear system for suppressing natural distractors.

The official soundtrack to “Five shades of grey”: Generalization in multimodal distractor-based retrieval

When responding to two events in a sequence, the repetition or change of stimuli and the accompanying response can benefit or interfere with response execution: Full repetition leads to benefits in performance while partial repetition leads to costs. Additionally, even distractor stimuli can be integrated with a response, and can, upon repetition, lead to benefits or interference. Recently it has been suggested that not only identical, but also perceptually similar distractors retrieve a previous response (Singh et al., Attention, Perception, & Psychophysics, 78(8), 2307-2312, 2016): Participants discriminated four visual shapes appearing in five different shades of grey, the latter being irrelevant for task execution. Exact distractor repetitions yielded the strongest distractor-based retrieval effect, which decreased with increasing dissimilarity between shades of grey. In the current study, we expand these findings by conceptually replicating Singh et al. (2016) using multimodal stimuli. In Experiment 1 (N=31), participants discriminated four visual targets accompanied by five auditory distractors. In Experiment 2 (N=32), participants discriminated four auditory targets accompanied by five visual distractors. We replicated the generalization of distractor-based retrieval – that is, the distractor-based retrieval effect decreased with increasing distractor-dissimilarity. These results not only show that generalization in distractor-based retrieval occurs in multimodal feature processing, but also that these processes can occur for distractors perceived in a different modality to that of the target.

Does the Perceptual Load Hypothesis Predict Auditory Distractibility?

Attention is a valuable resource with limited capacity, so knowing what will distract us during important tasks can be crucial in life. There is a lot of support for the Perceptual Load Hypothesis (PLH) when examining visual distractibility, however, less research has examined if PLH can predict auditory distractibility. Participants in the current study completed visual selective attention tasks while being presented with auditory and visual distractions under low/high perceptual loads. While visual distractors had a larger effect on the visual selective attention task, we increased auditory distractor effects by requiring participants to periodically respond to the auditory information. Our results showed no support for PLH with auditory distractors, and instead showed the opposite pattern, with auditory distractors having a larger effect under high perceptual load. These findings have important implications for our understanding of selective attention and shed light on tasks that require the processing of multisensory information.