New preprint!

Fri, 24 Jul 2026 00:00:00 +0000

Hello there!

A new preprint is out! link

The systematic oculomotor effects of vestibular stimulation are well known. However, the literature has generally assumed these biases to be largely reactive (that is, passive consequences of the stimulation, almost reflexive). Here, using a more ecological approach – namely, free viewing of images – we provide evidence for an adaptive component: depending on the context and on the strength of nausea, visual sampling and exploration are progressively driven towards more salient low-level image features. In other words, the stronger the motion sickness and nausea, the more visual exploration is guided by objectively salient visual features at the expense of volitional (top-down) processes, especially for highly arousing / threatening images. Concurrently, pupillometry reveals larger tonic pupil size, consistent with heightened arousal, as well as disrupted phasic responses to affective pictures.

Conscious perception emerges from the integration of bodily and environmental signals, with interoception playing a central role in shaping affective experience. In other words, how we perceive the environment depends, quite literally, on how we feel. With a little poetic license: with these results we are implying that perception may become dull when experiencing nausea, though it may also gain a stronger grip onto the physical structure of reality.

Kudos to Irene Petrizzo and many thanks to CIMeC UniTrento for the amazing support.

You can access the preprint here: https://doi.org/10.64898/2026.07.17.739163

Abstract

Perception is not a passive recording of external events. It is a continuous, active, and dynamic process of inference shaped by current goals, past experience, and hard biological constraints. The physiological state of the body is arguably the most fundamental constraint. Continuous inference about interoceptive states colors perception with emotions, which in turn affect basic perceptual and attentional processes. How, then, do we really look at the world when experiencing malaise?

Here we leverage Galvanic Vestibular Stimulation (GVS) – a non-invasive brain stimulation technique that induces mild dizziness, motion sickness, and nausea – in conjunction with high-resolution eye tracking, pupillometry, and computational modelling. We demonstrate that mild vestibular perturbations disrupt the coupling between gaze and informative low-level visual features. Crucially, however, this effect depends on individual susceptibility and on stimulus valence. Particularly susceptible participants experiencing stronger motion sickness increased their reliance on visually salient features, and particularly so for threatening (negatively valenced) images. Pupillometry revealed larger tonic pupil size in these participants, consistent with heightened arousal, as well as altered phasic responses to affective pictures. There was a close relationship between subjective reports of nausea, oculomotor behavior, and pupillary dynamics, highlighting an important role of inter-individual differences and related modulators (e.g., interoceptive accuracy).

Altogether, these results unveil the continuous and dynamic interplay between interoceptive and exteroceptive processes, showing that how we perceive the environment fundamentally resonates with how we feel.

Highlights

GVS caused variable degrees of dizziness and nausea

GVS led to spatial biases in visual exploration which were, however, further dependent on image valence and content

During GVS eye fixations landed, on average, at locations that were less salient based on their mere physical properties, provided participants did not experience strong interoceptive perturbations

Highly susceptible participants showed the opposite pattern: their fixations landed on visually more salient and informative locations, especially for negative images

Participants who felt stronger effects, including motion sickness, also showed the largest increase in tonic pupil size; concurrently, the signature phasic dilation associated with negative emotions was disrupted

Oculomotor behavior and perception adjust dynamically to ongoing interoceptive processes; GVS can be an effective tool to study this dialogue, provided that inter-individual differences are accounted for

autnoomic response | Elvio A. Blini

New preprint!

Abstract

Highlights