Flexibility to multisensory contestual information in people with sensory disabilities.

Project Information

FLEX-U

Grant agreement ID: 101064748

DOI

10.3030/101064748

Project closed

EC signature date 13 May 2022

Start date 16 February 2023

End date 15 February 2026

Funded under

• Marie Skłodowska-Curie Actions (MSCA)

Total cost

No data

EU contribution

€ 263 392,32

Coordinated by

FONDAZIONE ISTITUTO ITALIANO DI TECNOLOGIA
Italy

Periodic Reporting for period 2 - FLEX-U (Flexibility to multisensory contestual information in people with sensory disabilities.)

Reporting period: 2025-02-16 to 2026-02-15

Summary of the context and overall objectives of the project

Sensory perception is a dynamic and flexible process that allows people to interact with their environment. The perceptual flexibility is not uniform and may be influenced by experience, sensory modality, and the presence of sensory impairments. The FLEX-U project (Flexibility to Multisensory Contextual Information in People with Sensory Disabilities) investigates how individuals integrate and adapt to multisensory information, with a particular focus on differences between people with typical sensory function and those with sensory impairments such as blindness or deafness.

The essence of the project is how sensory information is weighted and adjusted in response to perceptual context. While people with typical sensory development tend to modulate their perception in response to contextual cues, those with sensory impairments may show either enhanced compensatory processing or reduced ability to adapt to changes in sensory input. Understanding these mechanisms is crucial for both advancing theoretical neuroscience and enabling practical applications in assistive technology and rehabilitation.

The project addresses two key challenges:

- Understanding Sensory Flexibility and Rigidity: By examining how individuals integrate and adjust to sensory information. This is why FLEX-U aims to determine whether sensory flexibility is a general trait or specific to certain modalities. This is particularly relevant for individuals with sensory impairments, who may either develop heightened abilities in other senses or, conversely, show more rigid sensory processing.

- Developing Models of Perceptual Behavior: Using computational models based on the Bayesian framework, the project attempts to quantify how different sensory cues influence perception. These models allow us to understand whether integration patterns, such as central tendency bias or serial dependence, emerge across sensory modalities, providing deeper insights into how the brain processes sensory information.

The implications of FLEX-U extend beyond fundamental research. By identifying differences in sensory flexibility, the project can help develop personalized rehabilitation strategies for individuals with sensory impairments. This knowledge can also inform the design of assistive technologies, such as sensory substitution devices and multisensory training programs, to improve interaction with the environment for those with visual or auditory deficits.
From a broader perspective, the findings of FLEX-U align with European strategic priorities on accessibility, inclusion, and technological innovation. In an increasingly digital and multisensory world, understanding how individuals process sensory information can help shape policies related to accessibility, inclusive education, and human-machine interaction. The project also integrates perspectives from social sciences and humanities, bridging cognitive neuroscience with real-world applications. In particular, it considers the ethical and societal implications of multisensory perception, ensuring that the research findings contribute to practical improvements in the lives of individuals with sensory impairments. By combining behavioral studies with computational modeling, FLEX-U seeks to provide a comprehensive understanding of sensory adaptation while fostering innovations that enhance accessibility and inclusivity.

Work performed from the beginning of the project to the end of the period covered by the report and main results achieved so far

During the FLEX-U project, a series of behavioral experiments and computational analyses were conducted to investigate how contextual information influences perceptual processes across sensory modalities. The project focused on understanding the flexibility of sensory systems and how perceptual estimates are shaped by prior experience and sensory reliability in both typical and sensory-impaired individuals.
The experimental work examined contextual effects across three main perceptual domains: spatial, temporal, and speed perception. In the spatial and temporal domains, the project investigated how auditory and visual information interact with contextual priors, particularly the central tendency effect. The results demonstrated that contextual influences depend strongly on the sensory modality involved and on task-specific sensory reliability. In particular, visual information tends to dominate spatial perception, whereas auditory information plays a leading role in temporal perception.
In the domain of speed perception, the project investigated both global contextual effects (central tendency) and local contextual effects (serial dependence). Experiments using auditory and visual stimuli revealed modality-specific patterns in the influence of contextual information on perceptual estimates. Additional cross-modal experiments comparing audiovisual and visuo-tactile speed perception further showed that contextual influences can operate either independently across modalities or through partially shared mechanisms, depending on the sensory combination.
A further important component of the project was the development and application of computational Bayesian modelling to explain perceptual biases and contextual influences on perception. These modelling approaches allowed the project to test theoretical predictions regarding how sensory information and prior knowledge are integrated during perceptual inference.
The project also introduced methodological advances by applying continuous tracking paradigms to study multisensory motion perception. This approach enabled the dynamic measurement of perceptual responses over time and provided an efficient alternative to traditional psychophysical methods.
In addition to studies conducted with typically developing participants, the project extended these investigations to individuals with sensory deprivation, particularly blind participants. These studies provided new insights into how contextual information and perceptual priors operate in the absence of vision and revealed differences in how perceptual biases manifest across sensory experiences.
Overall, the FLEX-U project has generated significant scientific outputs. The research conducted within the project resulted in four peer-reviewed publications (including one recently accepted article) and two additional manuscripts currently in preparation. The findings advance the state of the art in multisensory perception research by providing new empirical evidence and modelling approaches to understand how contextual information shapes perceptual inference.

Progress beyond the state of the art and expected potential impact (including the socio-economic impact and the wider societal implications of the project so far)

The FLEX-U project has advanced the state of the art in multisensory perception by providing new insights into how contextual information influences perceptual inference across sensory modalities. While previous research has often examined contextual effects within single sensory modalities, FLEX-U systematically investigated how contextual priors operate across vision, audition, and touch and across different perceptual domains, including spatial, temporal, and speed perception.
A key result of the project is the demonstration that contextual effects such as central tendency and serial dependence are strongly influenced by modality-specific sensory reliability rather than by a single supramodal prior. These findings challenge simplified models of perceptual inference and support a framework in which perceptual estimates depend on flexible weighting of sensory information, depending on task demands and sensory uncertainty.
Another important contribution of the project concerns the development and application of computational Bayesian modelling approaches to explain perceptual biases. These models provide a quantitative framework to describe how sensory inputs and prior knowledge interact during perceptual estimation and represent a step forward in integrating behavioural experiments with computational theories of perception.
The project also introduced methodological advances by using continuous-tracking paradigms to investigate multisensory motion perception. This approach enables dynamic measurement of perceptual responses and provides an efficient alternative to traditional psychophysical methods.
Furthermore, FLEX-U extended these investigations to individuals with sensory deprivation, particularly blind participants, revealing how contextual priors may operate differently depending on sensory experience. These results provide new insights into how perceptual systems adapt in the absence of vision and contribute to a better understanding of sensory plasticity.
To ensure further uptake and development of these results, several directions for future work can be identified. Further research could extend these investigations to additional clinical populations, such as deaf individuals, and explore how contextual mechanisms operate across different sensory impairments. Additional studies could also further develop the computational models proposed in the project and test them in more complex multisensory environments.
The findings from the FLEX-U project also have potential implications for rehabilitation research and assistive technologies, as understanding how contextual information influences perception could inform the development of training protocols to enhance sensory calibration and perceptual learning.
Overall, the project advances the current state of knowledge in multisensory perception by combining behavioral experiments, computational modelling, and research on sensory impairment, and provides a foundation for future interdisciplinary research in cognitive neuroscience and sensory rehabilitation.